ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
GLIBCXX_CONDITIONAL(ENABLE_BACKTRACE, [test "$enable_libstdcxx_backtrace" = yes])
])
+dnl
+dnl Allow the emergency EH pool to be configured.
+dnl
+dnl --enable-libstdcxx-static-eh-pool will cause a fixed-size static buffer
+dnl to be used for allocating exceptions after malloc fails. The default is
+dnl to allocate a buffer using malloc
+dnl
+dnl --with-libstdcxx-eh-pool-obj-count=N will set the default size for the
+dnl buffer. For a static buffer that size is fixed permanently. For a dynamic
+dnl buffer it's the default, but it can be overridden from the environment.
+dnl
+dnl To set the default to approximately the same values as GCC 12,
+dnl use --with-libstdcxx-eh-pool-obj-count=94 for 32-bit targets,
+dnl and --with-libstdcxx-eh-pool-obj-count=252 for 64-bit targets.
+dnl
+dnl Defines:
+dnl _GLIBCXX_EH_POOL_STATIC if a fixed-size static buffer should be used
+dnl instead of allocating a buffer on startup.
+dnl _GLIBCXX_EH_POOL_NOBJS to override the default EMERGENCY_OBJ_COUNT value.
+dnl
+AC_DEFUN([GLIBCXX_EMERGENCY_EH_ALLOC], [
+ eh_pool_static=
+ eh_pool_nobjs=
+ AC_ARG_ENABLE([libstdcxx-static-eh-pool],
+ AC_HELP_STRING([--enable-libstdcxx-static-eh-pool],
+ [use a fixed-size static buffer for allocating exceptions if malloc fails]),
+ [if test "${enableval}" = yes; then
+ eh_pool_static="-D_GLIBCXX_EH_POOL_STATIC"
+ AC_MSG_NOTICE([EH pool using static buffer])
+ fi],)
+
+ AC_ARG_WITH([libstdcxx-eh-pool-obj-count],
+ AC_HELP_STRING([--with-libstdcxx-eh-pool-obj-count],
+ [the number of exceptions that can be allocated from the pool if malloc fails]),
+ [if test "${withval}" -ge 0 2>/dev/null; then
+ eh_pool_obj_count="-D_GLIBCXX_EH_POOL_NOBJS=${withval}"
+ AC_MSG_NOTICE([EH pool object count: ${withval}])
+ else
+ AC_MSG_ERROR([EH pool obj count must be a non-negative integer: $withval])
+ fi],)
+
+ EH_POOL_FLAGS="$eh_pool_static $eh_pool_obj_count"
+ AC_SUBST(EH_POOL_FLAGS)
+])
+
# Macros from the top-level gcc directory.
m4_include([../config/gc++filt.m4])
m4_include([../config/tls.m4])
DOXYGEN
BUILD_INFO_FALSE
BUILD_INFO_TRUE
+EH_POOL_FLAGS
ENABLE_BACKTRACE_FALSE
ENABLE_BACKTRACE_TRUE
BACKTRACE_SUPPORTS_THREADS
enable_libstdcxx_threads
enable_libstdcxx_filesystem_ts
enable_libstdcxx_backtrace
+enable_libstdcxx_static_eh_pool
+with_libstdcxx_eh_pool_obj_count
enable_cet
with_gxx_include_dir
enable_version_specific_runtime_libs
turns on ISO/IEC TS 18822 support [default=auto]
--enable-libstdcxx-backtrace
turns on libbacktrace support [default=auto]
+ --enable-libstdcxx-static-eh-pool
+ use a fixed-size static buffer for allocating
+ exceptions if malloc fails
--enable-cet enable Intel CET in target libraries [default=auto]
--enable-version-specific-runtime-libs
Specify that runtime libraries should be installed
--with-system-libunwind use installed libunwind
--with-default-libstdcxx-abi
set the std::string ABI to use by default
+ --with-libstdcxx-eh-pool-obj-count
+ the number of exceptions that can be allocated from
+ the pool if malloc fails
--with-gxx-include-dir=DIR
installation directory for include files
--with-toolexeclibdir=DIR
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 12206 "configure"
+#line 12215 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 12312 "configure"
+#line 12321 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
# Fake what AC_TRY_COMPILE does.
cat > conftest.$ac_ext << EOF
-#line 16012 "configure"
+#line 16021 "configure"
int main()
{
typedef bool atomic_type;
rm -f conftest*
cat > conftest.$ac_ext << EOF
-#line 16047 "configure"
+#line 16056 "configure"
int main()
{
typedef short atomic_type;
rm -f conftest*
cat > conftest.$ac_ext << EOF
-#line 16082 "configure"
+#line 16091 "configure"
int main()
{
// NB: _Atomic_word not necessarily int.
rm -f conftest*
cat > conftest.$ac_ext << EOF
-#line 16118 "configure"
+#line 16127 "configure"
int main()
{
typedef long long atomic_type;
# unnecessary for this test.
cat > conftest.$ac_ext << EOF
-#line 16274 "configure"
+#line 16283 "configure"
int main()
{
_Decimal32 d1;
# unnecessary for this test.
cat > conftest.$ac_ext << EOF
-#line 16316 "configure"
+#line 16325 "configure"
template<typename T1, typename T2>
struct same
{ typedef T2 type; };
fi
done
+ for ac_func in secure_getenv
+do :
+ ac_fn_c_check_func "$LINENO" "secure_getenv" "ac_cv_func_secure_getenv"
+if test "x$ac_cv_func_secure_getenv" = xyes; then :
+ cat >>confdefs.h <<_ACEOF
+#define HAVE_SECURE_GETENV 1
+_ACEOF
+
+fi
+done
+
fi
+# For libsupc++/eh_alloc.cc defaults.
+
+ eh_pool_static=
+ eh_pool_nobjs=
+ # Check whether --enable-libstdcxx-static-eh-pool was given.
+if test "${enable_libstdcxx_static_eh_pool+set}" = set; then :
+ enableval=$enable_libstdcxx_static_eh_pool; if test "${enableval}" = yes; then
+ eh_pool_static="-D_GLIBCXX_EH_POOL_STATIC"
+ { $as_echo "$as_me:${as_lineno-$LINENO}: EH pool using static buffer" >&5
+$as_echo "$as_me: EH pool using static buffer" >&6;}
+ fi
+fi
+
+
+
+# Check whether --with-libstdcxx-eh-pool-obj-count was given.
+if test "${with_libstdcxx_eh_pool_obj_count+set}" = set; then :
+ withval=$with_libstdcxx_eh_pool_obj_count; if test "${withval}" -ge 0 2>/dev/null; then
+ eh_pool_obj_count="-D_GLIBCXX_EH_POOL_NOBJS=${withval}"
+ { $as_echo "$as_me:${as_lineno-$LINENO}: EH pool object count: ${withval}" >&5
+$as_echo "$as_me: EH pool object count: ${withval}" >&6;}
+ else
+ as_fn_error $? "EH pool obj count must be a non-negative integer: $withval" "$LINENO" 5
+ fi
+fi
+
+
+ EH_POOL_FLAGS="$eh_pool_static $eh_pool_obj_count"
+
+
+
# Define documentation rules conditionally.
# See if makeinfo has been installed and is modern enough
# Check which release added std::exception_ptr for the target
GLIBCXX_CHECK_EXCEPTION_PTR_SYMVER
+# For libsupc++/eh_alloc.cc defaults.
+GLIBCXX_EMERGENCY_EH_ALLOC
+
# Define documentation rules conditionally.
# See if makeinfo has been installed and is modern enough
AC_CHECK_FUNCS(timespec_get)
AC_CHECK_FUNCS(sockatmark)
AC_CHECK_FUNCS(uselocale)
+ AC_CHECK_FUNCS(secure_getenv)
AM_ICONV
;;
*-mingw32*)
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
</p></div></div></div><hr /></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="book"><a href="manual/index.html">The GNU C++ Library Manual</a></span></dt><dd><dl><dt><span class="part"><a href="manual/intro.html">I.
Introduction
-</a></span></dt><dd><dl><dt><span class="chapter"><a href="manual/status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="manual/status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2014">C++ 2014</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2014.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2014.filesystemts">Filesystem TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2017.par2ts">Parallelism 2 TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2020">C++ 2020</a></span></dt><dt><span class="section"><a href="manual/status.html#status.iso.2023">C++ 2023</a></span></dt><dt><span class="section"><a href="manual/status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="manual/status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="manual/license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="manual/license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="manual/bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="manual/bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="manual/bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="manual/setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="manual/setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="manual/configure.html">Configure</a></span></dt><dt><span class="section"><a href="manual/make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="manual/using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="manual/using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="manual/using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="manual/debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dd><dl><dt><span class="section"><a href="manual/debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="manual/debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="part"><a href="manual/std_contents.html">II.
+</a></span></dt><dd><dl><dt><span class="chapter"><a href="manual/status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="manual/status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2014">C++ 2014</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2014.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2014.filesystemts">Filesystem TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.2017.par2ts">Parallelism 2 TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.2020">C++ 2020</a></span></dt><dt><span class="section"><a href="manual/status.html#status.iso.2023">C++ 2023</a></span></dt><dt><span class="section"><a href="manual/status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="manual/status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="manual/status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="manual/status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="manual/license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="manual/license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="manual/bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="manual/bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="manual/bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="manual/setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="manual/setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="manual/configure.html">Configure</a></span></dt><dt><span class="section"><a href="manual/make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="manual/using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="manual/using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="manual/using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="manual/using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="manual/using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="manual/using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="manual/using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="manual/using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.alloc">Memory allocation</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="manual/using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="manual/using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="manual/debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="manual/debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dd><dl><dt><span class="section"><a href="manual/debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="manual/debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="manual/debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="part"><a href="manual/std_contents.html">II.
Standard Contents
</a></span></dt><dd><dl><dt><span class="chapter"><a href="manual/support.html">4.
Support
Existing tests
</a></span></dt><dt><span class="section"><a href="manual/test.html#test.exception.safety.containers">
C++11 Requirements Test Sequence Descriptions
-</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="section"><a href="manual/abi.html">ABI Policy and Guidelines</a></span></dt><dd><dl><dt><span class="section"><a href="manual/abi.html#abi.cxx_interface">The C++ Interface</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.versioning">Versioning</a></span></dt><dd><dl><dt><span class="section"><a href="manual/abi.html#abi.versioning.goals">Goals</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.versioning.history">History</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.versioning.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.versioning.config">Configuring</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.versioning.active">Checking Active</a></span></dt></dl></dd><dt><span class="section"><a href="manual/abi.html#abi.changes_allowed">Allowed Changes</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.changes_no">Prohibited Changes</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.impl">Implementation</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.testing">Testing</a></span></dt><dd><dl><dt><span class="section"><a href="manual/abi.html#abi.testing.single">Single ABI Testing</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.testing.multi">Multiple ABI Testing</a></span></dt></dl></dd><dt><span class="section"><a href="manual/abi.html#abi.issues">Outstanding Issues</a></span></dt></dl></dd><dt><span class="section"><a href="manual/api.html">API Evolution and Deprecation History</a></span></dt><dd><dl><dt><span class="section"><a href="manual/api.html#api.rel_300"><code class="constant">3.0</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_310"><code class="constant">3.1</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_320"><code class="constant">3.2</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_330"><code class="constant">3.3</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_340"><code class="constant">3.4</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_400"><code class="constant">4.0</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_410"><code class="constant">4.1</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_420"><code class="constant">4.2</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_430"><code class="constant">4.3</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_440"><code class="constant">4.4</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_450"><code class="constant">4.5</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_460"><code class="constant">4.6</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_470"><code class="constant">4.7</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_480"><code class="constant">4.8</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_490"><code class="constant">4.9</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_51"><code class="constant">5</code></a></span></dt><dd><dl><dt><span class="section"><a href="manual/api.html#api.rel_53"><code class="constant">5.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="manual/api.html#api.rel_61"><code class="constant">6</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_71"><code class="constant">7</code></a></span></dt><dd><dl><dt><span class="section"><a href="manual/api.html#api.rel_72"><code class="constant">7.2</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_73"><code class="constant">7.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="manual/api.html#api.rel_81"><code class="constant">8</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_91"><code class="constant">9</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_101"><code class="constant">10</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_111"><code class="constant">11</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_121"><code class="constant">12</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_123"><code class="constant">12.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="manual/backwards.html">Backwards Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="manual/backwards.html#backwards.first">First</a></span></dt><dt><span class="section"><a href="manual/backwards.html#backwards.second">Second</a></span></dt><dt><span class="section"><a href="manual/backwards.html#backwards.third">Third</a></span></dt><dd><dl><dt><span class="section"><a href="manual/backwards.html#backwards.third.headers">Pre-ISO headers removed</a></span></dt><dt><span class="section"><a href="manual/backwards.html#backwards.third.hash">Extension headers hash_map, hash_set moved to ext or backwards</a></span></dt><dt><span class="section"><a href="manual/backwards.html#backwards.third.nocreate_noreplace">No <code class="code">ios::nocreate/ios::noreplace</code>.
+</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="section"><a href="manual/abi.html">ABI Policy and Guidelines</a></span></dt><dd><dl><dt><span class="section"><a href="manual/abi.html#abi.cxx_interface">The C++ Interface</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.versioning">Versioning</a></span></dt><dd><dl><dt><span class="section"><a href="manual/abi.html#abi.versioning.goals">Goals</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.versioning.history">History</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.versioning.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.versioning.config">Configuring</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.versioning.active">Checking Active</a></span></dt></dl></dd><dt><span class="section"><a href="manual/abi.html#abi.changes_allowed">Allowed Changes</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.changes_no">Prohibited Changes</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.impl">Implementation</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.testing">Testing</a></span></dt><dd><dl><dt><span class="section"><a href="manual/abi.html#abi.testing.single">Single ABI Testing</a></span></dt><dt><span class="section"><a href="manual/abi.html#abi.testing.multi">Multiple ABI Testing</a></span></dt></dl></dd><dt><span class="section"><a href="manual/abi.html#abi.issues">Outstanding Issues</a></span></dt></dl></dd><dt><span class="section"><a href="manual/api.html">API Evolution and Deprecation History</a></span></dt><dd><dl><dt><span class="section"><a href="manual/api.html#api.rel_300"><code class="constant">3.0</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_310"><code class="constant">3.1</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_320"><code class="constant">3.2</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_330"><code class="constant">3.3</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_340"><code class="constant">3.4</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_400"><code class="constant">4.0</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_410"><code class="constant">4.1</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_420"><code class="constant">4.2</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_430"><code class="constant">4.3</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_440"><code class="constant">4.4</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_450"><code class="constant">4.5</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_460"><code class="constant">4.6</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_470"><code class="constant">4.7</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_480"><code class="constant">4.8</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_490"><code class="constant">4.9</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_51"><code class="constant">5</code></a></span></dt><dd><dl><dt><span class="section"><a href="manual/api.html#api.rel_53"><code class="constant">5.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="manual/api.html#api.rel_61"><code class="constant">6</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_71"><code class="constant">7</code></a></span></dt><dd><dl><dt><span class="section"><a href="manual/api.html#api.rel_72"><code class="constant">7.2</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_73"><code class="constant">7.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="manual/api.html#api.rel_81"><code class="constant">8</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_91"><code class="constant">9</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_101"><code class="constant">10</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_111"><code class="constant">11</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_121"><code class="constant">12</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_123"><code class="constant">12.3</code></a></span></dt><dt><span class="section"><a href="manual/api.html#api.rel_131"><code class="constant">13</code></a></span></dt></dl></dd><dt><span class="section"><a href="manual/backwards.html">Backwards Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="manual/backwards.html#backwards.first">First</a></span></dt><dt><span class="section"><a href="manual/backwards.html#backwards.second">Second</a></span></dt><dt><span class="section"><a href="manual/backwards.html#backwards.third">Third</a></span></dt><dd><dl><dt><span class="section"><a href="manual/backwards.html#backwards.third.headers">Pre-ISO headers removed</a></span></dt><dt><span class="section"><a href="manual/backwards.html#backwards.third.hash">Extension headers hash_map, hash_set moved to ext or backwards</a></span></dt><dt><span class="section"><a href="manual/backwards.html#backwards.third.nocreate_noreplace">No <code class="code">ios::nocreate/ios::noreplace</code>.
</a></span></dt><dt><span class="section"><a href="manual/backwards.html#backwards.third.streamattach">
No <code class="code">stream::attach(int fd)</code>
</a></span></dt><dt><span class="section"><a href="manual/backwards.html#backwards.third.support_cxx98">
</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="api.rel_123"></a><code class="constant">12.3</code></h3></div></div></div><p>
Calling a <code class="code">std::bind</code> result as volatile is ill-formed for C++20
and later.
+</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="api.rel_131"></a><code class="constant">13</code></h3></div></div></div><p>
+Tunables <span style="color: red"><variable>glibcxx.eh_pool.obj_count</variable></span> and
+<span style="color: red"><variable>glibcxx.eh_pool.obj_size</variable></span> were added.
</p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="abi.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="appendix_porting.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="backwards.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">ABI Policy and Guidelines </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Backwards Compatibility</td></tr></table></div></body></html>
\ No newline at end of file
Existing tests
</a></span></dt><dt><span class="section"><a href="test.html#test.exception.safety.containers">
C++11 Requirements Test Sequence Descriptions
-</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="section"><a href="abi.html">ABI Policy and Guidelines</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.cxx_interface">The C++ Interface</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning">Versioning</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.versioning.goals">Goals</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.history">History</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.config">Configuring</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.active">Checking Active</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.changes_allowed">Allowed Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.changes_no">Prohibited Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.impl">Implementation</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing">Testing</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.testing.single">Single ABI Testing</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing.multi">Multiple ABI Testing</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.issues">Outstanding Issues</a></span></dt></dl></dd><dt><span class="section"><a href="api.html">API Evolution and Deprecation History</a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_300"><code class="constant">3.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_310"><code class="constant">3.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_320"><code class="constant">3.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_330"><code class="constant">3.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_340"><code class="constant">3.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_400"><code class="constant">4.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_410"><code class="constant">4.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_420"><code class="constant">4.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_430"><code class="constant">4.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_440"><code class="constant">4.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_450"><code class="constant">4.5</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_460"><code class="constant">4.6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_470"><code class="constant">4.7</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_480"><code class="constant">4.8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_490"><code class="constant">4.9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_51"><code class="constant">5</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_53"><code class="constant">5.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_61"><code class="constant">6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_71"><code class="constant">7</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_72"><code class="constant">7.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_73"><code class="constant">7.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_81"><code class="constant">8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_91"><code class="constant">9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_101"><code class="constant">10</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_111"><code class="constant">11</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_121"><code class="constant">12</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_123"><code class="constant">12.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="backwards.html">Backwards Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.first">First</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.second">Second</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third">Third</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.third.headers">Pre-ISO headers removed</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.hash">Extension headers hash_map, hash_set moved to ext or backwards</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.nocreate_noreplace">No <code class="code">ios::nocreate/ios::noreplace</code>.
+</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="section"><a href="abi.html">ABI Policy and Guidelines</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.cxx_interface">The C++ Interface</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning">Versioning</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.versioning.goals">Goals</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.history">History</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.config">Configuring</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.active">Checking Active</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.changes_allowed">Allowed Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.changes_no">Prohibited Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.impl">Implementation</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing">Testing</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.testing.single">Single ABI Testing</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing.multi">Multiple ABI Testing</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.issues">Outstanding Issues</a></span></dt></dl></dd><dt><span class="section"><a href="api.html">API Evolution and Deprecation History</a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_300"><code class="constant">3.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_310"><code class="constant">3.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_320"><code class="constant">3.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_330"><code class="constant">3.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_340"><code class="constant">3.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_400"><code class="constant">4.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_410"><code class="constant">4.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_420"><code class="constant">4.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_430"><code class="constant">4.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_440"><code class="constant">4.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_450"><code class="constant">4.5</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_460"><code class="constant">4.6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_470"><code class="constant">4.7</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_480"><code class="constant">4.8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_490"><code class="constant">4.9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_51"><code class="constant">5</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_53"><code class="constant">5.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_61"><code class="constant">6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_71"><code class="constant">7</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_72"><code class="constant">7.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_73"><code class="constant">7.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_81"><code class="constant">8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_91"><code class="constant">9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_101"><code class="constant">10</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_111"><code class="constant">11</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_121"><code class="constant">12</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_123"><code class="constant">12.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_131"><code class="constant">13</code></a></span></dt></dl></dd><dt><span class="section"><a href="backwards.html">Backwards Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.first">First</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.second">Second</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third">Third</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.third.headers">Pre-ISO headers removed</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.hash">Extension headers hash_map, hash_set moved to ext or backwards</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.nocreate_noreplace">No <code class="code">ios::nocreate/ios::noreplace</code>.
</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.streamattach">
No <code class="code">stream::attach(int fd)</code>
</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.support_cxx98">
Existing tests
</a></span></dt><dt><span class="section"><a href="test.html#test.exception.safety.containers">
C++11 Requirements Test Sequence Descriptions
-</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="section"><a href="abi.html">ABI Policy and Guidelines</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.cxx_interface">The C++ Interface</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning">Versioning</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.versioning.goals">Goals</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.history">History</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.config">Configuring</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.active">Checking Active</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.changes_allowed">Allowed Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.changes_no">Prohibited Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.impl">Implementation</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing">Testing</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.testing.single">Single ABI Testing</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing.multi">Multiple ABI Testing</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.issues">Outstanding Issues</a></span></dt></dl></dd><dt><span class="section"><a href="api.html">API Evolution and Deprecation History</a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_300"><code class="constant">3.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_310"><code class="constant">3.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_320"><code class="constant">3.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_330"><code class="constant">3.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_340"><code class="constant">3.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_400"><code class="constant">4.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_410"><code class="constant">4.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_420"><code class="constant">4.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_430"><code class="constant">4.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_440"><code class="constant">4.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_450"><code class="constant">4.5</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_460"><code class="constant">4.6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_470"><code class="constant">4.7</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_480"><code class="constant">4.8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_490"><code class="constant">4.9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_51"><code class="constant">5</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_53"><code class="constant">5.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_61"><code class="constant">6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_71"><code class="constant">7</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_72"><code class="constant">7.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_73"><code class="constant">7.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_81"><code class="constant">8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_91"><code class="constant">9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_101"><code class="constant">10</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_111"><code class="constant">11</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_121"><code class="constant">12</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_123"><code class="constant">12.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="backwards.html">Backwards Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.first">First</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.second">Second</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third">Third</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.third.headers">Pre-ISO headers removed</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.hash">Extension headers hash_map, hash_set moved to ext or backwards</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.nocreate_noreplace">No <code class="code">ios::nocreate/ios::noreplace</code>.
+</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="section"><a href="abi.html">ABI Policy and Guidelines</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.cxx_interface">The C++ Interface</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning">Versioning</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.versioning.goals">Goals</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.history">History</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.config">Configuring</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.active">Checking Active</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.changes_allowed">Allowed Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.changes_no">Prohibited Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.impl">Implementation</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing">Testing</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.testing.single">Single ABI Testing</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing.multi">Multiple ABI Testing</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.issues">Outstanding Issues</a></span></dt></dl></dd><dt><span class="section"><a href="api.html">API Evolution and Deprecation History</a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_300"><code class="constant">3.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_310"><code class="constant">3.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_320"><code class="constant">3.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_330"><code class="constant">3.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_340"><code class="constant">3.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_400"><code class="constant">4.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_410"><code class="constant">4.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_420"><code class="constant">4.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_430"><code class="constant">4.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_440"><code class="constant">4.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_450"><code class="constant">4.5</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_460"><code class="constant">4.6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_470"><code class="constant">4.7</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_480"><code class="constant">4.8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_490"><code class="constant">4.9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_51"><code class="constant">5</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_53"><code class="constant">5.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_61"><code class="constant">6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_71"><code class="constant">7</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_72"><code class="constant">7.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_73"><code class="constant">7.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_81"><code class="constant">8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_91"><code class="constant">9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_101"><code class="constant">10</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_111"><code class="constant">11</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_121"><code class="constant">12</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_123"><code class="constant">12.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_131"><code class="constant">13</code></a></span></dt></dl></dd><dt><span class="section"><a href="backwards.html">Backwards Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.first">First</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.second">Second</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third">Third</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.third.headers">Pre-ISO headers removed</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.hash">Extension headers hash_map, hash_set moved to ext or backwards</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.nocreate_noreplace">No <code class="code">ios::nocreate/ios::noreplace</code>.
</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.streamattach">
No <code class="code">stream::attach(int fd)</code>
</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.support_cxx98">
<span class="emphasis"><em>freestanding</em></span> environment, in which only a
minimal set of headers are provided. This option builds such an
environment.
- </p></dd><dt><span class="term"><code class="code">--disable-libstdcxx-verbose</code></span></dt><dd><p>
+ </p></dd><dt><span class="term"><code class="code">--disable-libstdcxx-hosted</code></span></dt><dd><p>This is an alias for <code class="code">--disable-hosted-libstdcxx</code>.</p></dd><dt><span class="term"><code class="code">--disable-libstdcxx-verbose</code></span></dt><dd><p>
By default, the library is configured to write descriptive messages
to standard error for certain events such as calling a pure virtual
function or the invocation of the standard terminate handler. Those
as the usual libstdc++ and libsupc++ libraries. This is enabled by
default on select POSIX targets where it is known to work and disabled
otherwise.
+ </p></dd><dt><span class="term"><code class="code">--enable-libstdcxx-static-eh-pool</code></span></dt><dd><p>Use a fixed-size static buffer for the emergency exception handling
+ pool (see <a class="xref" href="using_exceptions.html#intro.using.exception.alloc" title="Memory allocation">Memory allocation for exceptions</a>). The default
+ is to allocate the pool on program startup using <code class="code">malloc</code>.
+ With this option, a static buffer will be provided by libstdc++ instead.
+ This does not change the library ABI.
+ </p></dd><dt><span class="term"><code class="code">--with-libstdcxx-eh-pool-obj-count=NUM</code></span></dt><dd><p>Set the size of the emergency exception handling pool. NUM is the
+ number of simultaneous allocated exceptions to support.
+ This does not change the library ABI.
</p></dd></dl></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="setup.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="setup.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="make.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 2. Setup </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Make</td></tr></table></div></body></html>
\ No newline at end of file
</p></div></div><hr /></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="part"><a href="intro.html">I.
Introduction
-</a></span></dt><dd><dl><dt><span class="chapter"><a href="status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2014">C++ 2014</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2014.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2014.filesystemts">Filesystem TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.par2ts">Parallelism 2 TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="status.html#status.iso.2020">C++ 2020</a></span></dt><dt><span class="section"><a href="status.html#status.iso.2023">C++ 2023</a></span></dt><dt><span class="section"><a href="status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="configure.html">Configure</a></span></dt><dt><span class="section"><a href="make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="part"><a href="std_contents.html">II.
+</a></span></dt><dd><dl><dt><span class="chapter"><a href="status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2014">C++ 2014</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2014.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2014.filesystemts">Filesystem TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.par2ts">Parallelism 2 TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="status.html#status.iso.2020">C++ 2020</a></span></dt><dt><span class="section"><a href="status.html#status.iso.2023">C++ 2023</a></span></dt><dt><span class="section"><a href="status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="configure.html">Configure</a></span></dt><dt><span class="section"><a href="make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.alloc">Memory allocation</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="part"><a href="std_contents.html">II.
Standard Contents
</a></span></dt><dd><dl><dt><span class="chapter"><a href="support.html">4.
Support
Existing tests
</a></span></dt><dt><span class="section"><a href="test.html#test.exception.safety.containers">
C++11 Requirements Test Sequence Descriptions
-</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="section"><a href="abi.html">ABI Policy and Guidelines</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.cxx_interface">The C++ Interface</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning">Versioning</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.versioning.goals">Goals</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.history">History</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.config">Configuring</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.active">Checking Active</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.changes_allowed">Allowed Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.changes_no">Prohibited Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.impl">Implementation</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing">Testing</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.testing.single">Single ABI Testing</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing.multi">Multiple ABI Testing</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.issues">Outstanding Issues</a></span></dt></dl></dd><dt><span class="section"><a href="api.html">API Evolution and Deprecation History</a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_300"><code class="constant">3.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_310"><code class="constant">3.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_320"><code class="constant">3.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_330"><code class="constant">3.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_340"><code class="constant">3.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_400"><code class="constant">4.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_410"><code class="constant">4.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_420"><code class="constant">4.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_430"><code class="constant">4.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_440"><code class="constant">4.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_450"><code class="constant">4.5</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_460"><code class="constant">4.6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_470"><code class="constant">4.7</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_480"><code class="constant">4.8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_490"><code class="constant">4.9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_51"><code class="constant">5</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_53"><code class="constant">5.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_61"><code class="constant">6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_71"><code class="constant">7</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_72"><code class="constant">7.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_73"><code class="constant">7.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_81"><code class="constant">8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_91"><code class="constant">9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_101"><code class="constant">10</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_111"><code class="constant">11</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_121"><code class="constant">12</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_123"><code class="constant">12.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="backwards.html">Backwards Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.first">First</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.second">Second</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third">Third</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.third.headers">Pre-ISO headers removed</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.hash">Extension headers hash_map, hash_set moved to ext or backwards</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.nocreate_noreplace">No <code class="code">ios::nocreate/ios::noreplace</code>.
+</a></span></dt></dl></dd></dl></dd></dl></dd><dt><span class="section"><a href="abi.html">ABI Policy and Guidelines</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.cxx_interface">The C++ Interface</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning">Versioning</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.versioning.goals">Goals</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.history">History</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.config">Configuring</a></span></dt><dt><span class="section"><a href="abi.html#abi.versioning.active">Checking Active</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.changes_allowed">Allowed Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.changes_no">Prohibited Changes</a></span></dt><dt><span class="section"><a href="abi.html#abi.impl">Implementation</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing">Testing</a></span></dt><dd><dl><dt><span class="section"><a href="abi.html#abi.testing.single">Single ABI Testing</a></span></dt><dt><span class="section"><a href="abi.html#abi.testing.multi">Multiple ABI Testing</a></span></dt></dl></dd><dt><span class="section"><a href="abi.html#abi.issues">Outstanding Issues</a></span></dt></dl></dd><dt><span class="section"><a href="api.html">API Evolution and Deprecation History</a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_300"><code class="constant">3.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_310"><code class="constant">3.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_320"><code class="constant">3.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_330"><code class="constant">3.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_340"><code class="constant">3.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_400"><code class="constant">4.0</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_410"><code class="constant">4.1</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_420"><code class="constant">4.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_430"><code class="constant">4.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_440"><code class="constant">4.4</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_450"><code class="constant">4.5</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_460"><code class="constant">4.6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_470"><code class="constant">4.7</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_480"><code class="constant">4.8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_490"><code class="constant">4.9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_51"><code class="constant">5</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_53"><code class="constant">5.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_61"><code class="constant">6</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_71"><code class="constant">7</code></a></span></dt><dd><dl><dt><span class="section"><a href="api.html#api.rel_72"><code class="constant">7.2</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_73"><code class="constant">7.3</code></a></span></dt></dl></dd><dt><span class="section"><a href="api.html#api.rel_81"><code class="constant">8</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_91"><code class="constant">9</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_101"><code class="constant">10</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_111"><code class="constant">11</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_121"><code class="constant">12</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_123"><code class="constant">12.3</code></a></span></dt><dt><span class="section"><a href="api.html#api.rel_131"><code class="constant">13</code></a></span></dt></dl></dd><dt><span class="section"><a href="backwards.html">Backwards Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.first">First</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.second">Second</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third">Third</a></span></dt><dd><dl><dt><span class="section"><a href="backwards.html#backwards.third.headers">Pre-ISO headers removed</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.hash">Extension headers hash_map, hash_set moved to ext or backwards</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.nocreate_noreplace">No <code class="code">ios::nocreate/ios::noreplace</code>.
</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.streamattach">
No <code class="code">stream::attach(int fd)</code>
</a></span></dt><dt><span class="section"><a href="backwards.html#backwards.third.support_cxx98">
</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="index.html">Prev</a> </td><th width="60%" align="center">The GNU C++ Library Manual</th><td width="20%" align="right"> <a accesskey="n" href="status.html">Next</a></td></tr></table><hr /></div><div class="part"><div class="titlepage"><div><div><h1 class="title"><a id="manual.intro"></a>Part I.Â
Introduction
<a id="id-1.3.3.1.1.1" class="indexterm"></a>
-</h1></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="chapter"><a href="status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2014">C++ 2014</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2014.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2014.filesystemts">Filesystem TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.par2ts">Parallelism 2 TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="status.html#status.iso.2020">C++ 2020</a></span></dt><dt><span class="section"><a href="status.html#status.iso.2023">C++ 2023</a></span></dt><dt><span class="section"><a href="status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="configure.html">Configure</a></span></dt><dt><span class="section"><a href="make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt></dl></dd></dl></dd></dl></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="index.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="index.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="status.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">The GNU C++ Library Manual </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 1. Status</td></tr></table></div></body></html>
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+</h1></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="chapter"><a href="status.html">1. Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#manual.intro.status.iso">Implementation Status</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#status.iso.1998">C++ 1998/2003</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.1998.status">Implementation Status</a></span></dt><dt><span class="section"><a href="status.html#iso.1998.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2011">C++ 2011</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2011.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.2014">C++ 2014</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2014.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2014.filesystemts">Filesystem TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="status.html#status.iso.2017">C++ 2017</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.specific">Implementation Specific Behavior</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.2017.par2ts">Parallelism 2 TS</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="status.html#status.iso.2020">C++ 2020</a></span></dt><dt><span class="section"><a href="status.html#status.iso.2023">C++ 2023</a></span></dt><dt><span class="section"><a href="status.html#status.iso.tr1">C++ TR1</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.tr1.specific">Implementation Specific Behavior</a></span></dt></dl></dd><dt><span class="section"><a href="status.html#status.iso.tr24733">C++ TR 24733</a></span></dt><dt><span class="section"><a href="status.html#status.iso.specfun">C++ IS 29124</a></span></dt><dd><dl><dt><span class="section"><a href="status.html#iso.specfun.specific">Implementation Specific Behavior</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="license.html">License</a></span></dt><dd><dl><dt><span class="section"><a href="license.html#manual.intro.status.license.gpl">The Code: GPL</a></span></dt><dt><span class="section"><a href="license.html#manual.intro.status.license.fdl">The Documentation: GPL, FDL</a></span></dt></dl></dd><dt><span class="section"><a href="bugs.html">Bugs</a></span></dt><dd><dl><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.impl">Implementation Bugs</a></span></dt><dt><span class="section"><a href="bugs.html#manual.intro.status.bugs.iso">Standard Bugs</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="setup.html">2. Setup</a></span></dt><dd><dl><dt><span class="section"><a href="setup.html#manual.intro.setup.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="configure.html">Configure</a></span></dt><dt><span class="section"><a href="make.html">Make</a></span></dt></dl></dd><dt><span class="chapter"><a href="using.html">3. Using</a></span></dt><dd><dl><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.alloc">Memory allocation</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt></dl></dd></dl></dd></dl></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="index.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="index.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="status.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">The GNU C++ Library Manual </td><td width="20%" align="center"><a 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Introduction
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href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt></dl></dd></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="manual.intro.using.flags"></a>Command Options</h2></div></div></div><p>
+</th><td width="20%" align="right"> <a accesskey="n" href="using_headers.html">Next</a></td></tr></table><hr /></div><div class="chapter"><div class="titlepage"><div><div><h2 class="title"><a id="manual.intro.using"></a>Chapter 3. Using</h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="section"><a href="using.html#manual.intro.using.flags">Command Options</a></span></dt><dt><span class="section"><a href="using_headers.html">Headers</a></span></dt><dd><dl><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.all">Header Files</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.mixing">Mixing Headers</a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.cheaders">The C Headers and <code class="code">namespace std</code></a></span></dt><dt><span class="section"><a href="using_headers.html#manual.intro.using.headers.pre">Precompiled Headers</a></span></dt></dl></dd><dt><span class="section"><a href="using_macros.html">Macros</a></span></dt><dt><span class="section"><a href="using_dual_abi.html">Dual ABI</a></span></dt><dd><dl><dt><span class="section"><a href="using_dual_abi.html#manual.intro.using.abi.trouble">Troubleshooting</a></span></dt></dl></dd><dt><span class="section"><a href="using_namespaces.html">Namespaces</a></span></dt><dd><dl><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.all">Available Namespaces</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.std">namespace std</a></span></dt><dt><span class="section"><a href="using_namespaces.html#manual.intro.using.namespaces.comp">Using Namespace Composition</a></span></dt></dl></dd><dt><span class="section"><a href="using_dynamic_or_shared.html">Linking</a></span></dt><dd><dl><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.freestanding">Almost Nothing</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.dynamic">Finding Dynamic or Shared Libraries</a></span></dt><dt><span class="section"><a href="using_dynamic_or_shared.html#manual.intro.using.linkage.experimental">Experimental Library Extensions</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html">Concurrency</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.prereq">Prerequisites</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.thread_safety">Thread Safety</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.atomics">Atomics</a></span></dt><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.io">IO</a></span></dt><dd><dl><dt><span class="section"><a href="using_concurrency.html#concurrency.io.structure">Structure</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.defaults">Defaults</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.future">Future</a></span></dt><dt><span class="section"><a href="using_concurrency.html#concurrency.io.alt">Alternatives</a></span></dt></dl></dd><dt><span class="section"><a href="using_concurrency.html#manual.intro.using.concurrency.containers">Containers</a></span></dt></dl></dd><dt><span class="section"><a href="using_exceptions.html">Exceptions</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.safety">Exception Safety</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.propagating">Exception Neutrality</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.alloc">Memory allocation</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.no">Doing without</a></span></dt><dt><span class="section"><a href="using_exceptions.html#intro.using.exception.compat">Compatibility</a></span></dt><dd><dl><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.c">With <code class="literal">C</code></a></span></dt><dt><span class="section"><a href="using_exceptions.html#using.exception.compat.posix">With <code class="literal">POSIX</code> thread cancellation</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="debug.html">Debugging Support</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.compiler">Using <span class="command"><strong>g++</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.req">Debug Versions of Library Binary Files</a></span></dt><dt><span class="section"><a href="debug.html#debug.memory">Memory Leak Hunting</a></span></dt><dd><dl><dt><span class="section"><a href="debug.html#debug.memory.mtalloc">Non-memory leaks in Pool and MT allocators</a></span></dt></dl></dd><dt><span class="section"><a href="debug.html#debug.races">Data Race Hunting</a></span></dt><dt><span class="section"><a href="debug.html#debug.gdb">Using <span class="command"><strong>gdb</strong></span></a></span></dt><dt><span class="section"><a href="debug.html#debug.exceptions">Tracking uncaught exceptions</a></span></dt><dt><span class="section"><a href="debug.html#debug.debug_mode">Debug Mode</a></span></dt><dt><span class="section"><a href="debug.html#debug.compile_time_checks">Compile Time Checking</a></span></dt></dl></dd></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="manual.intro.using.flags"></a>Command Options</h2></div></div></div><p>
The set of features available in the GNU C++ library is shaped by
several <a class="link" href="http://gcc.gnu.org/onlinedocs/gcc-4.3.2/gcc/Invoking-GCC.html" target="_top">GCC
Command Options</a>. Options that impact libstdc++ are
The constructors of <code class="classname">thread</code> that take a
callable function argument swallow all exceptions resulting from
executing the function argument.
- </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="intro.using.exception.no"></a>Doing without</h3></div></div></div><p>
+ </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="intro.using.exception.alloc"></a>Memory allocation</h3></div></div></div><p>
+ When the program throws an exception the runtime will obtain storage for
+ a <code class="code">__cxa_exception</code> header and the thrown object itself.
+ Libstdc++ will try to use <code class="code">malloc</code> to obtain storage,
+ but provides an emergency buffer to be used if malloc fails,
+ as described by the <a class="link" href="https://itanium-cxx-abi.github.io/cxx-abi/abi-eh.html#imp-emergency" target="_top">Itanium
+ exception handling ABI</a>.
+ </p><p>
+ Contrary to the ABI, the libstdc++ emergency buffer is not always 64kB,
+ and does not always allocate 1kB chunks. The buffer is used as a pool for
+ variable-sized allocations, so that it doesn't waste space for smaller
+ exception objects such as <code class="code">std::bad_alloc</code>.
+ The total size of the buffer is scaled appropriately for the target.
+ Specifically it depends on <code class="code">sizeof(void*)</code>, so that a 64-bit
+ system uses a larger pool than a 32-bit system. This is done because for
+ 32-bit systems the exception objects (and the exception header) require
+ less space, and core counts and thread counts are typically lower as well.
+ </p><p>
+ By default, libstdc++ will use <code class="code">malloc</code> to allocate the buffer
+ on program startup.
+ <a class="xref" href="configure.html" title="Configure">Configuring</a> libstdc++ with the
+ <code class="code">--enable-libstdcxx-static-eh-pool</code> option will make it
+ use a static buffer instead of using <code class="code">malloc</code>.
+ </p><p>
+ The buffer size is chosen automatically, but can be overridden
+ by configuring with <code class="code">--with-libstdcxx-eh-pool-obj-count=NUM</code>,
+ where <code class="code">NUM</code> is the number of simultaneous allocations that
+ should be supported. The size of the pool will be sufficient for
+ <code class="code">NUM</code> exceptions of <code class="code">6 * sizeof(void*)</code> bytes,
+ plus another <code class="code">NUM</code> exceptions captured in
+ <code class="classname">std::exception_ptr</code> and rethrown using
+ <code class="code">std::rethrow_exception</code>. The buffer size determined by the
+ obj-count value applies whether the buffer is reserved as static storage
+ or is allocated dynamically.
+ Setting obj-count to zero will disable the pool, so that no emergency
+ buffer is present.
+ </p><p>
+ For a dynamic buffer, the default size can also be changed at runtime,
+ per-process, via the <code class="literal">GLIBCXX_TUNABLES</code> environment
+ variable.
+ The <code class="literal">GLIBCXX_TUNABLES</code> environment variable should be
+ a string of colon-separated <span class="emphasis"><em>name=value</em></span> pairs. The
+ following names will be recognized, with the specified semantics:
+ </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="code">glibcxx.eh_pool.obj_count</code></span></dt><dd>
+ The number of exception objects to provide space for in the pool.
+ The value must be a non-negative integer and has the same meaning as the
+ <code class="code">--with-libstdcxx-eh-pool-obj-count</code> option for
+ <code class="filename">configure</code>.
+ </dd><dt><span class="term"><code class="code">glibcxx.eh_pool.obj_size</code></span></dt><dd>
+ The expected size of exception objects that the pool might get used for.
+ The value must be a positive integer, and is measured in units of
+ <code class="code">sizeof(void*)</code>. The default value is <code class="literal">6</code>
+ which is large enough to store any exception type thrown by libstdc++.
+ Exceptions larger than this can still be allocated from the pool,
+ but larger exceptions will exhaust the pool more rapidly.
+ </dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="intro.using.exception.no"></a>Doing without</h3></div></div></div><p>
C++ is a language that strives to be as efficient as is possible
in delivering features. As such, considerable care is used by both
language implementer and designers to make sure unused features
}
catch(...)
{ this->_M_setstate(ios_base::badbit); }
-</pre></div></div><div class="bibliography"><div class="titlepage"><div><div><h3 class="title"><a id="using.exceptions.biblio"></a>Bibliography</h3></div></div></div><div class="biblioentry"><a id="id-1.3.3.4.9.9.2"></a><p><span class="title"><em>
+</pre></div></div><div class="bibliography"><div class="titlepage"><div><div><h3 class="title"><a id="using.exceptions.biblio"></a>Bibliography</h3></div></div></div><div class="biblioentry"><a id="id-1.3.3.4.9.10.2"></a><p><span class="title"><em>
<a class="link" href="http://www.opengroup.org/austin/" target="_top">
System Interface Definitions, Issue 7 (IEEE Std. 1003.1-2008)
</a>
. </span><span class="copyright">Copyright © 2008
The Open Group/The Institute of Electrical and Electronics
Engineers, Inc.
- . </span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.9.3"></a><p><span class="title"><em>
+ . </span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.10.3"></a><p><span class="title"><em>
<a class="link" href="https://www.boost.org/community/error_handling.html" target="_top">
Error and Exception Handling
</a>
</em>. </span><span class="author"><span class="firstname">David</span> <span class="surname">Abrahams </span>. </span><span class="publisher"><span class="publishername">
Boost
- . </span></span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.9.4"></a><p><span class="title"><em>
+ . </span></span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.10.4"></a><p><span class="title"><em>
<a class="link" href="https://www.boost.org/community/exception_safety.html" target="_top">
Exception-Safety in Generic Components
</a>
</em>. </span><span class="author"><span class="firstname">David</span> <span class="surname">Abrahams</span>. </span><span class="publisher"><span class="publishername">
Boost
- . </span></span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.9.5"></a><p><span class="title"><em>
+ . </span></span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.10.5"></a><p><span class="title"><em>
<a class="link" href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/1997/N1077.pdf" target="_top">
Standard Library Exception Policy
</a>
</em>. </span><span class="author"><span class="firstname">Matt</span> <span class="surname">Austern</span>. </span><span class="publisher"><span class="publishername">
WG21 N1077
- . </span></span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.9.6"></a><p><span class="title"><em>
+ . </span></span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.10.6"></a><p><span class="title"><em>
<a class="link" href="http://gcc.gnu.org/ml/gcc-patches/2001-03/msg00661.html" target="_top">
ia64 c++ abi exception handling
</a>
</em>. </span><span class="author"><span class="firstname">Richard</span> <span class="surname">Henderson</span>. </span><span class="publisher"><span class="publishername">
GNU
- . </span></span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.9.7"></a><p><span class="title"><em>
+ . </span></span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.10.7"></a><p><span class="title"><em>
<a class="link" href="https://www.stroustrup.com/3rd_safe.pdf" target="_top">
Appendix E: Standard-Library Exception Safety
</a>
- </em>. </span><span class="author"><span class="firstname">Bjarne</span> <span class="surname">Stroustrup</span>. </span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.9.8"></a><p><span class="citetitle"><em class="citetitle">
+ </em>. </span><span class="author"><span class="firstname">Bjarne</span> <span class="surname">Stroustrup</span>. </span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.10.8"></a><p><span class="citetitle"><em class="citetitle">
Exceptional C++
</em>. </span><span class="pagenums">
Exception-Safety Issues and Techniques
- . </span><span class="author"><span class="firstname">Herb</span> <span class="surname">Sutter</span>. </span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.9.9"></a><p><span class="title"><em>
+ . </span><span class="author"><span class="firstname">Herb</span> <span class="surname">Sutter</span>. </span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.10.9"></a><p><span class="title"><em>
<a class="link" href="http://gcc.gnu.org/PR25191" target="_top">
GCC Bug 25191: exception_defines.h #defines try/catch
</a>
+ </em>. </span></p></div><div class="biblioentry"><a id="id-1.3.3.4.9.10.10"></a><p><span class="title"><em>
+ <a class="link" href="https://www.gnu.org/software/libc/manual/html_node/Tunables.html" target="_top">
+ Tunables, The GNU C Library
+ </a>
</em>. </span></p></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="using_concurrency.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="using.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="debug.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Concurrency </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Debugging Support</td></tr></table></div></body></html>
\ No newline at end of file
</para>
</listitem></varlistentry>
+ <varlistentry><term><code>--disable-libstdcxx-hosted</code></term>
+ <listitem>
+ <para>This is an alias for <code>--disable-hosted-libstdcxx</code>.</para>
+ </listitem></varlistentry>
+
<varlistentry><term><code>--disable-libstdcxx-verbose</code></term>
<listitem>
<para>
</para>
</listitem></varlistentry>
+ <varlistentry><term><code>--enable-libstdcxx-static-eh-pool</code></term>
+ <listitem>
+ <para>Use a fixed-size static buffer for the emergency exception handling
+ pool (see <xref linkend="intro.using.exception.alloc"/>). The default
+ is to allocate the pool on program startup using <code>malloc</code>.
+ With this option, a static buffer will be provided by libstdc++ instead.
+ This does not change the library ABI.
+ </para>
+ </listitem></varlistentry>
+
+ <varlistentry><term><code>--with-libstdcxx-eh-pool-obj-count=NUM</code></term>
+ <listitem>
+ <para>Set the size of the emergency exception handling pool. NUM is the
+ number of simultaneous allocated exceptions to support.
+ This does not change the library ABI.
+ </para>
+ </listitem></varlistentry>
+
</variablelist>
</section>
</section>
+<section xml:id="api.rel_131"><info><title><constant>13</constant></title></info>
+
+<para>
+Tunables <variable>glibcxx.eh_pool.obj_count</variable> and
+<variable>glibcxx.eh_pool.obj_size</variable> were added.
+</para>
+
+</section>
+
</section>
</section>
+<section xml:id="intro.using.exception.alloc" xreflabel="Memory allocation for exceptions"><info><title>Memory allocation</title></info>
+
+ <para>
+ When the program throws an exception the runtime will obtain storage for
+ a <code>__cxa_exception</code> header and the thrown object itself.
+ Libstdc++ will try to use <code>malloc</code> to obtain storage,
+ but provides an emergency buffer to be used if malloc fails,
+ as described by the <link xmlns:xlink="http://www.w3.org/1999/xlink"
+ xlink:href="https://itanium-cxx-abi.github.io/cxx-abi/abi-eh.html#imp-emergency">Itanium
+ exception handling ABI</link>.
+ </para>
+
+ <para>
+ Contrary to the ABI, the libstdc++ emergency buffer is not always 64kB,
+ and does not always allocate 1kB chunks. The buffer is used as a pool for
+ variable-sized allocations, so that it doesn't waste space for smaller
+ exception objects such as <code>std::bad_alloc</code>.
+ The total size of the buffer is scaled appropriately for the target.
+ Specifically it depends on <code>sizeof(void*)</code>, so that a 64-bit
+ system uses a larger pool than a 32-bit system. This is done because for
+ 32-bit systems the exception objects (and the exception header) require
+ less space, and core counts and thread counts are typically lower as well.
+ </para>
+
+ <para>
+ By default, libstdc++ will use <code>malloc</code> to allocate the buffer
+ on program startup.
+ <xref linkend="manual.intro.setup.configure"/> libstdc++ with the
+ <code>--enable-libstdcxx-static-eh-pool</code> option will make it
+ use a static buffer instead of using <code>malloc</code>.
+ </para>
+
+ <para>
+ The buffer size is chosen automatically, but can be overridden
+ by configuring with <code>--with-libstdcxx-eh-pool-obj-count=NUM</code>,
+ where <code>NUM</code> is the number of simultaneous allocations that
+ should be supported. The size of the pool will be sufficient for
+ <code>NUM</code> exceptions of <code>6 * sizeof(void*)</code> bytes,
+ plus another <code>NUM</code> exceptions captured in
+ <classname>std::exception_ptr</classname> and rethrown using
+ <code>std::rethrow_exception</code>. The buffer size determined by the
+ obj-count value applies whether the buffer is reserved as static storage
+ or is allocated dynamically.
+ Setting obj-count to zero will disable the pool, so that no emergency
+ buffer is present.
+ </para>
+
+ <para>
+ For a dynamic buffer, the default size can also be changed at runtime,
+ per-process, via the <literal>GLIBCXX_TUNABLES</literal> environment
+ variable.
+ The <literal>GLIBCXX_TUNABLES</literal> environment variable should be
+ a string of colon-separated <emphasis>name=value</emphasis> pairs. The
+ following names will be recognized, with the specified semantics:
+ </para>
+
+ <variablelist>
+ <varlistentry>
+ <term><code>glibcxx.eh_pool.obj_count</code></term>
+ <listitem>
+ The number of exception objects to provide space for in the pool.
+ The value must be a non-negative integer and has the same meaning as the
+ <code>--with-libstdcxx-eh-pool-obj-count</code> option for
+ <filename>configure</filename>.
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><code>glibcxx.eh_pool.obj_size</code></term>
+ <listitem>
+ The expected size of exception objects that the pool might get used for.
+ The value must be a positive integer, and is measured in units of
+ <code>sizeof(void*)</code>. The default value is <literal>6</literal>
+ which is large enough to store any exception type thrown by libstdc++.
+ Exceptions larger than this can still be allocated from the pool,
+ but larger exceptions will exhaust the pool more rapidly.
+ </listitem>
+ </varlistentry>
+ </variablelist>
+
+</section>
+
<section xml:id="intro.using.exception.no" xreflabel="-fno-exceptions"><info><title>Doing without</title></info>
<para>
</title>
</biblioentry>
+ <biblioentry>
+ <title>
+ <link xmlns:xlink="http://www.w3.org/1999/xlink"
+ xlink:href="https://www.gnu.org/software/libc/manual/html_node/Tunables.html">
+ Tunables, The GNU C Library
+ </link>
+ </title>
+ </biblioentry>
+
</bibliography>
</section>
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
# as the occasion call for it.
AM_CXXFLAGS = \
$(glibcxx_lt_pic_flag) $(glibcxx_compiler_shared_flag) \
- $(XTEMPLATE_FLAGS) $(FREESTANDING_FLAGS) \
+ $(XTEMPLATE_FLAGS) $(FREESTANDING_FLAGS) $(EH_POOL_FLAGS) \
$(WARN_CXXFLAGS) $(OPTIMIZE_CXXFLAGS) $(CONFIG_CXXFLAGS)
AM_MAKEFLAGS = \
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
# as the occasion call for it.
AM_CXXFLAGS = \
$(glibcxx_lt_pic_flag) $(glibcxx_compiler_shared_flag) \
- $(XTEMPLATE_FLAGS) $(FREESTANDING_FLAGS) \
+ $(XTEMPLATE_FLAGS) $(FREESTANDING_FLAGS) $(EH_POOL_FLAGS) \
$(WARN_CXXFLAGS) $(OPTIMIZE_CXXFLAGS) $(CONFIG_CXXFLAGS)
AM_MAKEFLAGS = \
// This is derived from the C++ ABI for IA-64. Where we diverge
// for cross-architecture compatibility are noted with "@@@".
-#include <bits/c++config.h>
-#include <cstdlib>
+#include <exception> // std::exception
+#include <new> // std::terminate
+#include <cstdlib> // std::malloc, std::free, std::strtoul
+#include <climits> // INT_MAX
+#include <bits/stl_function.h> // std::less
+#include "unwind-cxx.h"
#if _GLIBCXX_HOSTED
-#include <cstring>
+# include <string_view> // std::string_view
+# include <cstring> // std::strchr, std::memset
+# include <ext/concurrence.h> // __gnu_cxx::__mutex, __gnu_cxx::__scoped_lock
#endif
-#include <climits>
-#include <exception>
-#include "unwind-cxx.h"
-#include <ext/concurrence.h>
-#include <new>
+
+// We use an emergency buffer used for exceptions when malloc fails.
+// If _GLIBCXX_EH_POOL_STATIC is defined (e.g. by configure) then we use
+// a fixed-size static buffer. Otherwise, allocate on startup using malloc.
+//
+// The size of the buffer is N * (S * P + R + D), where:
+// N == The number of objects to reserve space for.
+// Defaults to EMERGENCY_OBJ_COUNT, defined below.
+// S == Estimated size of exception objects to account for.
+// This size is in units of sizeof(void*) not bytes.
+// Defaults to EMERGENCY_OBJ_SIZE, defined below.
+// P == sizeof(void*).
+// R == sizeof(__cxa_refcounted_exception).
+// D == sizeof(__cxa_dependent_exception).
+//
+// This provides space for N thrown exceptions of S words each, and an
+// additional N dependent exceptions from std::rethrow_exception.
+//
+// The calculation allows values of N and S to be target-independent,
+// as the size will be scaled by the size of basic types on the target,
+// and space for the C++ exception header (__cxa_refcounted_exception)
+// is added automatically.
+//
+// For a dynamically allocated buffer, N and S can be set from the environment.
+// Setting N=0 will disable the emergency buffer.
+// The GLIBCXX_TUNABLES environment variable will be checked for the following:
+// - Tunable glibcxx.eh_pool.obj_count overrides EMERGENCY_OBJ_COUNT.
+// - Tunable glibcxx.eh_pool.obj_size overrides EMERGENCY_OBJ_SIZE.
#if _GLIBCXX_HOSTED
using std::free;
using namespace __cxxabiv1;
-// ??? How to control these parameters.
-
-// Guess from the size of basic types how large a buffer is reasonable.
-// Note that the basic c++ exception header has 13 pointers and 2 ints,
-// so on a system with PSImode pointers we're talking about 56 bytes
-// just for overhead.
-
-#if INT_MAX == 32767
-# define EMERGENCY_OBJ_SIZE 128
-# define EMERGENCY_OBJ_COUNT 16
-#elif !defined (_GLIBCXX_LLP64) && LONG_MAX == 2147483647
-# define EMERGENCY_OBJ_SIZE 512
-# define EMERGENCY_OBJ_COUNT 32
+// Assume that 6 * sizeof(void*) is a reasonable exception object size.
+// Throwing very many large objects will exhaust the pool more quickly.
+// N.B. sizeof(std::bad_alloc) == sizeof(void*)
+// and sizeof(std::runtime_error) == 2 * sizeof(void*)
+// and sizeof(std::system_error) == 4 * sizeof(void*).
+#define EMERGENCY_OBJ_SIZE 6
+
+#ifdef __GTHREADS
+// Assume that the number of concurrent exception objects scales with the
+// processor word size, i.e., 16-bit systems are not likely to have hundreds
+// of threads all simultaneously throwing on OOM conditions.
+# define EMERGENCY_OBJ_COUNT (4 * __SIZEOF_POINTER__ * __SIZEOF_POINTER__)
+# define MAX_OBJ_COUNT (16 << __SIZEOF_POINTER__)
#else
-# define EMERGENCY_OBJ_SIZE 1024
-# define EMERGENCY_OBJ_COUNT 64
+# define EMERGENCY_OBJ_COUNT 4
+# define MAX_OBJ_COUNT 64
#endif
-#ifndef __GTHREADS
-# undef EMERGENCY_OBJ_COUNT
-# define EMERGENCY_OBJ_COUNT 4
+// This can be set by configure.
+#ifdef _GLIBCXX_EH_POOL_NOBJS
+# if _GLIBCXX_EH_POOL_NOBJS > MAX_OBJ_COUNT
+# warning "_GLIBCXX_EH_POOL_NOBJS value is too large; ignoring it"
+# else
+# undef EMERGENCY_OBJ_COUNT
+# define EMERGENCY_OBJ_COUNT _GLIBCXX_EH_POOL_NOBJS
+# endif
#endif
namespace __gnu_cxx
{
- void __freeres();
+ void __freeres() noexcept;
}
namespace
{
+ static constexpr std::size_t
+ buffer_size_in_bytes(std::size_t obj_count, std::size_t obj_size) noexcept
+ {
+ // N * (S * P + R + D)
+ constexpr std::size_t P = sizeof(void*);
+ constexpr std::size_t R = sizeof(__cxa_refcounted_exception);
+ constexpr std::size_t D = sizeof(__cxa_dependent_exception);
+ return obj_count * (obj_size * P + R + D);
+ }
+
// A fixed-size heap, variable size object allocator
class pool
{
public:
- pool();
+ pool() noexcept;
- _GLIBCXX_NODISCARD void *allocate (std::size_t);
- void free (void *);
+ _GLIBCXX_NODISCARD void *allocate (std::size_t) noexcept;
+ void free (void *) noexcept;
- bool in_pool (void *);
+ bool in_pool (void *) const noexcept;
private:
struct free_entry {
char data[] __attribute__((aligned));
};
+#ifdef __GTHREADS
// A single mutex controlling emergency allocations.
__gnu_cxx::__mutex emergency_mutex;
+ using __scoped_lock = __gnu_cxx::__scoped_lock;
+#else
+ int emergency_mutex = 0;
+ struct __scoped_lock { explicit __scoped_lock(int) { } };
+#endif
// The free-list
- free_entry *first_free_entry;
+ free_entry *first_free_entry = nullptr;
// The arena itself - we need to keep track of these only
// to implement in_pool.
- char *arena;
- std::size_t arena_size;
+#ifdef _GLIBCXX_EH_POOL_STATIC
+ static constexpr std::size_t arena_size
+ = buffer_size_in_bytes(EMERGENCY_OBJ_COUNT, EMERGENCY_OBJ_SIZE);
+ alignas(void*) char arena[std::max(arena_size, sizeof(free_entry))];
+#else
+ char *arena = nullptr;
+ std::size_t arena_size = 0;
+#endif
- friend void __gnu_cxx::__freeres();
+ friend void __gnu_cxx::__freeres() noexcept;
};
- pool::pool()
+ pool::pool() noexcept
{
- // Allocate the arena - we could add a GLIBCXX_EH_ARENA_SIZE environment
- // to make this tunable.
- arena_size = (EMERGENCY_OBJ_SIZE * EMERGENCY_OBJ_COUNT
- + EMERGENCY_OBJ_COUNT * sizeof (__cxa_dependent_exception));
+#ifndef _GLIBCXX_EH_POOL_STATIC
+ int obj_size = EMERGENCY_OBJ_SIZE;
+ int obj_count = EMERGENCY_OBJ_COUNT;
+
+#if _GLIBCXX_HOSTED
+#if _GLIBCXX_HAVE_SECURE_GETENV
+ const char* str = ::secure_getenv("GLIBCXX_TUNABLES");
+#else
+ const char* str = std::getenv("GLIBCXX_TUNABLES");
+#endif
+ const std::string_view ns_name = "glibcxx.eh_pool";
+ std::pair<std::string_view, int> tunables[]{
+ {"obj_size", 0}, {"obj_count", obj_count}
+ };
+ while (str)
+ {
+ if (*str == ':')
+ ++str;
+
+ if (!ns_name.compare(0, ns_name.size(), str, ns_name.size())
+ && str[ns_name.size()] == '.')
+ {
+ str += ns_name.size() + 1;
+ for (auto& t : tunables)
+ if (!t.first.compare(0, t.first.size(), str, t.first.size())
+ && str[t.first.size()] == '=')
+ {
+ str += t.first.size() + 1;
+ char* end;
+ unsigned long val = strtoul(str, &end, 0);
+ if ((*end == ':' || *end == '\0') && val <= INT_MAX)
+ t.second = val;
+ str = end;
+ break;
+ }
+ }
+ str = strchr(str, ':');
+ }
+ obj_count = std::min(tunables[1].second, MAX_OBJ_COUNT); // Can be zero.
+ if (tunables[0].second != 0)
+ obj_size = tunables[0].second;
+#endif // HOSTED
+
+ arena_size = buffer_size_in_bytes(obj_count, obj_size);
+ if (arena_size == 0)
+ return;
arena = (char *)malloc (arena_size);
if (!arena)
{
// If the allocation failed go without an emergency pool.
arena_size = 0;
- first_free_entry = NULL;
return;
}
+#endif // STATIC
// Populate the free-list with a single entry covering the whole arena
first_free_entry = reinterpret_cast <free_entry *> (arena);
first_free_entry->next = NULL;
}
- void *pool::allocate (std::size_t size)
+ void *pool::allocate (std::size_t size) noexcept
{
__gnu_cxx::__scoped_lock sentry(emergency_mutex);
// We need an additional size_t member plus the padding to
return &x->data;
}
- void pool::free (void *data)
+ void pool::free (void *data) noexcept
{
- __gnu_cxx::__scoped_lock sentry(emergency_mutex);
+ __scoped_lock sentry(emergency_mutex);
allocated_entry *e = reinterpret_cast <allocated_entry *>
(reinterpret_cast <char *> (data) - offsetof (allocated_entry, data));
std::size_t sz = e->size;
}
}
- bool pool::in_pool (void *ptr)
+ inline bool pool::in_pool (void *ptr) const noexcept
{
- char *p = reinterpret_cast <char *> (ptr);
- return (p > arena
- && p < arena + arena_size);
+ std::less<const void*> less;
+ return less(ptr, arena + arena_size) && less(arena, ptr);
}
pool emergency_pool;
namespace __gnu_cxx
{
+ __attribute__((cold))
void
- __freeres()
+ __freeres() noexcept
{
+#ifndef _GLIBCXX_EH_POOL_STATIC
if (emergency_pool.arena)
{
::free(emergency_pool.arena);
emergency_pool.arena = 0;
}
+#endif
}
}
extern "C" void *
-__cxxabiv1::__cxa_allocate_exception(std::size_t thrown_size) _GLIBCXX_NOTHROW
+__cxxabiv1::__cxa_allocate_exception(std::size_t thrown_size) noexcept
{
- void *ret;
-
thrown_size += sizeof (__cxa_refcounted_exception);
- ret = malloc (thrown_size);
+
+ void *ret = malloc (thrown_size);
if (!ret)
ret = emergency_pool.allocate (thrown_size);
extern "C" void
-__cxxabiv1::__cxa_free_exception(void *vptr) _GLIBCXX_NOTHROW
+__cxxabiv1::__cxa_free_exception(void *vptr) noexcept
{
char *ptr = (char *) vptr - sizeof (__cxa_refcounted_exception);
- if (emergency_pool.in_pool (ptr))
+ if (emergency_pool.in_pool (ptr)) [[__unlikely__]]
emergency_pool.free (ptr);
else
free (ptr);
extern "C" __cxa_dependent_exception*
-__cxxabiv1::__cxa_allocate_dependent_exception() _GLIBCXX_NOTHROW
+__cxxabiv1::__cxa_allocate_dependent_exception() noexcept
{
- __cxa_dependent_exception *ret;
-
- ret = static_cast<__cxa_dependent_exception*>
- (malloc (sizeof (__cxa_dependent_exception)));
+ void *ret = malloc (sizeof (__cxa_dependent_exception));
if (!ret)
- ret = static_cast <__cxa_dependent_exception*>
- (emergency_pool.allocate (sizeof (__cxa_dependent_exception)));
+ ret = emergency_pool.allocate (sizeof (__cxa_dependent_exception));
if (!ret)
std::terminate ();
memset (ret, 0, sizeof (__cxa_dependent_exception));
- return ret;
+ return static_cast<__cxa_dependent_exception*>(ret);
}
extern "C" void
__cxxabiv1::__cxa_free_dependent_exception
- (__cxa_dependent_exception *vptr) _GLIBCXX_NOTHROW
+ (__cxa_dependent_exception *vptr) noexcept
{
- if (emergency_pool.in_pool (vptr))
+ if (emergency_pool.in_pool (vptr)) [[__unlikely__]]
emergency_pool.free (vptr);
else
free (vptr);
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@
ECHO_N = @ECHO_N@
ECHO_T = @ECHO_T@
EGREP = @EGREP@
+EH_POOL_FLAGS = @EH_POOL_FLAGS@
ERROR_CONSTANTS_SRCDIR = @ERROR_CONSTANTS_SRCDIR@
EXEEXT = @EXEEXT@
EXTRA_CFLAGS = @EXTRA_CFLAGS@