1 dnl Process this file with autoconf to produce a configure script.
2 dnl Note we do not use AC_PREREQ here! See aclocal.m4 for what we use instead.
3 AC_INIT([GNU C Library], [(see version.h)], [https://sourceware.org/bugzilla/], [glibc])
4 AC_CONFIG_SRCDIR([include/features.h])
5 AC_CONFIG_HEADERS([config.h])
6 AC_CONFIG_AUX_DIR([scripts])
8 ACX_PKGVERSION([GNU libc])
9 ACX_BUGURL([http://www.gnu.org/software/libc/bugs.html])
10 AC_DEFINE_UNQUOTED([PKGVERSION], ["$PKGVERSION"],
11 [Package description])
12 AC_DEFINE_UNQUOTED([REPORT_BUGS_TO], ["$REPORT_BUGS_TO"],
13 [Bug reporting address])
15 # Glibc should not depend on any header files
16 AC_DEFUN([_AC_INCLUDES_DEFAULT_REQUIREMENTS],
17 [m4_divert_text([DEFAULTS],
18 [ac_includes_default='/* none */'])])
20 # We require GCC, and by default use its preprocessor. Override AC_PROG_CPP
21 # here to work around the Autoconf issue discussed in
22 # <https://sourceware.org/ml/libc-alpha/2013-01/msg00721.html>.
23 AC_DEFUN([AC_PROG_CPP],
24 [AC_REQUIRE([AC_PROG_CC])dnl
25 AC_ARG_VAR([CPP], [C preprocessor])dnl
26 _AC_ARG_VAR_CPPFLAGS()dnl
27 # On Suns, sometimes $CPP names a directory.
28 if test -n "$CPP" && test -d "$CPP"; then
31 if test -z "$CPP"; then
37 # We require GCC. Override _AC_PROG_CC_C89 here to work around the Autoconf
39 # <https://sourceware.org/ml/libc-alpha/2013-01/msg00757.html>.
40 AC_DEFUN([_AC_PROG_CC_C89], [[$1]])
42 dnl This is here so we can set $subdirs directly based on configure fragments.
48 if test $host != $build; then
49 AC_CHECK_PROGS(BUILD_CC, gcc cc)
51 AC_SUBST(cross_compiling)
53 AC_CHECK_TOOL(READELF, readelf, false)
55 # We need the C++ compiler only for testing.
57 # It's useless to us if it can't link programs (e.g. missing -lstdc++).
58 AC_CACHE_CHECK([whether $CXX can link programs], libc_cv_cxx_link_ok, [dnl
60 # Default, dynamic case.
61 AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
62 [libc_cv_cxx_link_ok=yes],
63 [libc_cv_cxx_link_ok=no])
65 old_LDFLAGS="$LDFLAGS"
66 LDFLAGS="$LDFLAGS -static"
67 AC_LINK_IFELSE([AC_LANG_SOURCE([
73 std::cout << "Hello, world!";
78 [libc_cv_cxx_link_ok=no])
79 LDFLAGS="$old_LDFLAGS"
81 AS_IF([test $libc_cv_cxx_link_ok != yes], [CXX=])
83 if test "`cd $srcdir; pwd -P`" = "`pwd -P`"; then
84 AC_MSG_ERROR([you must configure in a separate build directory])
87 # This will get text that should go into config.make.
90 # Check for a --with-gd argument and set libgd-LDFLAGS in config.make.
92 AC_HELP_STRING([--with-gd=DIR],
93 [find libgd include dir and library with prefix DIR]),
97 *) libgd_include="-I$withval/include"
98 libgd_ldflags="-L$withval/lib" ;;
101 AC_ARG_WITH([gd-include],
102 AC_HELP_STRING([--with-gd-include=DIR],
103 [find libgd include files in DIR]),
105 case "$with_gd_include" in
107 *) libgd_include="-I$withval" ;;
110 AC_ARG_WITH([gd-lib],
111 AC_HELP_STRING([--with-gd-lib=DIR],
112 [find libgd library files in DIR]),
114 case "$with_gd_lib" in
116 *) libgd_ldflags="-L$withval" ;;
120 if test -n "$libgd_include"; then
121 config_vars="$config_vars
122 CFLAGS-memusagestat.c = $libgd_include"
124 if test -n "$libgd_ldflags"; then
125 config_vars="$config_vars
126 libgd-LDFLAGS = $libgd_ldflags"
129 dnl Arguments to specify presence of other packages/features.
130 AC_ARG_WITH([binutils],
131 AC_HELP_STRING([--with-binutils=PATH],
132 [specify location of binutils (as and ld)]),
133 [path_binutils=$withval],
135 AC_ARG_WITH([selinux],
136 AC_HELP_STRING([--with-selinux],
137 [if building with SELinux support]),
138 [with_selinux=$withval],
141 AC_ARG_WITH([headers],
142 AC_HELP_STRING([--with-headers=PATH],
143 [location of system headers to use
144 (for example /usr/src/linux/include)
145 @<:@default=compiler default@:>@]),
146 [sysheaders=$withval],
150 AC_SUBST(use_default_link)
151 AC_ARG_WITH([default-link],
152 AC_HELP_STRING([--with-default-link],
153 [do not use explicit linker scripts]),
154 [use_default_link=$withval],
155 [use_default_link=default])
157 dnl Additional build flags injection.
158 AC_ARG_WITH([nonshared-cflags],
159 AC_HELP_STRING([--with-nonshared-cflags=CFLAGS],
160 [build nonshared libraries with additional CFLAGS]),
161 [extra_nonshared_cflags=$withval],
162 [extra_nonshared_cflags=])
163 AC_SUBST(extra_nonshared_cflags)
165 AC_ARG_ENABLE([sanity-checks],
166 AC_HELP_STRING([--disable-sanity-checks],
167 [really do not use threads (should not be used except in special situations) @<:@default=yes@:>@]),
168 [enable_sanity=$enableval],
171 AC_ARG_ENABLE([shared],
172 AC_HELP_STRING([--enable-shared],
173 [build shared library @<:@default=yes if GNU ld@:>@]),
176 AC_ARG_ENABLE([profile],
177 AC_HELP_STRING([--enable-profile],
178 [build profiled library @<:@default=no@:>@]),
179 [profile=$enableval],
181 AC_ARG_ENABLE([static-pie],
182 AC_HELP_STRING([--enable-static-pie],
183 [enable static PIE support and use it in the testsuite @<:@default=no@:>@]),
184 [static_pie=$enableval],
186 AC_ARG_ENABLE([timezone-tools],
187 AC_HELP_STRING([--disable-timezone-tools],
188 [do not install timezone tools @<:@default=install@:>@]),
189 [enable_timezone_tools=$enableval],
190 [enable_timezone_tools=yes])
191 AC_SUBST(enable_timezone_tools)
193 AC_ARG_ENABLE([hardcoded-path-in-tests],
194 AC_HELP_STRING([--enable-hardcoded-path-in-tests],
195 [hardcode newly built glibc path in tests @<:@default=no@:>@]),
196 [hardcoded_path_in_tests=$enableval],
197 [hardcoded_path_in_tests=no])
198 AC_SUBST(hardcoded_path_in_tests)
200 AC_ARG_ENABLE([stackguard-randomization],
201 AC_HELP_STRING([--enable-stackguard-randomization],
202 [initialize __stack_chk_guard canary with a random number at program start]),
203 [enable_stackguard_randomize=$enableval],
204 [enable_stackguard_randomize=no])
205 if test "$enable_stackguard_randomize" = yes; then
206 AC_DEFINE(ENABLE_STACKGUARD_RANDOMIZE)
209 AC_ARG_ENABLE([hidden-plt],
210 AC_HELP_STRING([--disable-hidden-plt],
211 [do not hide internal function calls to avoid PLT]),
214 if test "x$hidden" = xno; then
218 AC_ARG_ENABLE([bind-now],
219 AC_HELP_STRING([--enable-bind-now],
220 [disable lazy relocations in DSOs]),
221 [bindnow=$enableval],
224 if test "x$bindnow" = xyes; then
228 dnl Build glibc with -fstack-protector, -fstack-protector-all, or
229 dnl -fstack-protector-strong.
230 AC_ARG_ENABLE([stack-protector],
231 AC_HELP_STRING([--enable-stack-protector=@<:@yes|no|all|strong@:>@],
232 [Use -fstack-protector[-all|-strong] to detect glibc buffer overflows]),
233 [enable_stack_protector=$enableval],
234 [enable_stack_protector=no])
235 case "$enable_stack_protector" in
236 all|yes|no|strong) ;;
237 *) AC_MSG_ERROR([Not a valid argument for --enable-stack-protector: \"$enable_stack_protector\"]);;
240 dnl On some platforms we cannot use dynamic loading. We must provide
241 dnl static NSS modules.
242 AC_ARG_ENABLE([static-nss],
243 AC_HELP_STRING([--enable-static-nss],
244 [build static NSS modules @<:@default=no@:>@]),
245 [static_nss=$enableval],
247 dnl Enable static NSS also if we build no shared objects.
248 if test x"$static_nss" = xyes || test x"$shared" = xno; then
250 AC_DEFINE(DO_STATIC_NSS)
253 AC_ARG_ENABLE([force-install],
254 AC_HELP_STRING([--disable-force-install],
255 [don't force installation of files from this package, even if they are older than the installed files]),
256 [force_install=$enableval],
258 AC_SUBST(force_install)
260 AC_ARG_ENABLE([maintainer-mode],
261 AC_HELP_STRING([--enable-maintainer-mode],
262 [enable make rules and dependencies not useful (and sometimes confusing) to the casual installer]),
263 [maintainer=$enableval],
266 dnl On some platforms we allow dropping compatibility with all kernel
268 AC_ARG_ENABLE([kernel],
269 AC_HELP_STRING([--enable-kernel=VERSION],
270 [compile for compatibility with kernel not older than VERSION]),
271 [minimum_kernel=$enableval],
273 dnl Prevent unreasonable values.
274 if test "$minimum_kernel" = yes || test "$minimum_kernel" = no; then
275 # Better nothing than this.
278 if test "$minimum_kernel" = current; then
279 minimum_kernel=`uname -r 2>/dev/null` || minimum_kernel=
283 dnl For the development we sometimes want gcc to issue even more warnings.
284 dnl This is not the default since many of the extra warnings are not
286 AC_ARG_ENABLE([all-warnings],
287 AC_HELP_STRING([--enable-all-warnings],
288 [enable all useful warnings gcc can issue]),
289 [all_warnings=$enableval],
291 AC_SUBST(all_warnings)
293 AC_ARG_ENABLE([werror],
294 AC_HELP_STRING([--disable-werror],
295 [do not build with -Werror]),
296 [enable_werror=$enableval],
298 AC_SUBST(enable_werror)
300 AC_ARG_ENABLE([multi-arch],
301 AC_HELP_STRING([--enable-multi-arch],
302 [enable single DSO with optimizations for multiple architectures]),
303 [multi_arch=$enableval],
304 [multi_arch=default])
306 AC_ARG_ENABLE([experimental-malloc],
307 AC_HELP_STRING([--disable-experimental-malloc],
308 [disable experimental malloc features]),
309 [experimental_malloc=$enableval],
310 [experimental_malloc=yes])
311 AC_SUBST(experimental_malloc)
313 AC_ARG_ENABLE([crypt],
314 AC_HELP_STRING([--disable-crypt],
315 [do not build nor install the passphrase hashing library, libcrypt]),
316 [build_crypt=$enableval],
318 AC_SUBST(build_crypt)
320 AC_ARG_ENABLE([nss-crypt],
321 AC_HELP_STRING([--enable-nss-crypt],
322 [enable libcrypt to use nss]),
323 [nss_crypt=$enableval],
325 if test x$build_libcrypt = xno && test x$nss_crypt = xyes; then
326 AC_MSG_WARN([--enable-nss-crypt has no effect when libcrypt is disabled])
329 if test x$nss_crypt = xyes; then
330 nss_includes=-I$(nss-config --includedir 2>/dev/null)
331 if test $? -ne 0; then
332 AC_MSG_ERROR([cannot find include directory with nss-config])
334 nspr_includes=-I$(nspr-config --includedir 2>/dev/null)
335 if test $? -ne 0; then
336 AC_MSG_ERROR([cannot find include directory with nspr-config])
339 CFLAGS="$CFLAGS $nss_includes $nspr_includes"
340 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
342 #include <nsslowhash.h>
343 void f (void) { NSSLOW_Init (); }])],
344 libc_cv_nss_crypt=yes,
346 cannot find NSS headers with lowlevel hash function interfaces]))
348 old_LDFLAGS="$LDFLAGS"
349 LIBS="$LIBS -lfreebl3"
350 AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
352 #include <nsslowhash.h>],
354 libc_cv_nss_crypt=yes,
356 cannot link program using lowlevel NSS hash functions]))
357 # Check to see if there is a static NSS cryptographic library.
358 # If there isn't then we can't link anything with libcrypt.a,
359 # and that might mean disabling some static tests.
360 LDFLAGS="$LDFLAGS -static"
361 AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
363 #include <nsslowhash.h>],
365 libc_cv_static_nss_crypt=yes,
366 libc_cv_static_nss_crypt=no)
367 LDFLAGS="$old_LDFLAGS"
372 libc_cv_static_nss_crypt=no
374 AC_SUBST(libc_cv_nss_crypt)
375 AC_SUBST(libc_cv_static_nss_crypt)
378 AC_ARG_ENABLE([obsolete-rpc],
379 AC_HELP_STRING([--enable-obsolete-rpc],
380 [build and install the obsolete RPC code for link-time usage]),
381 [link_obsolete_rpc=$enableval],
382 [link_obsolete_rpc=no])
383 AC_SUBST(link_obsolete_rpc)
385 if test "$link_obsolete_rpc" = yes; then
386 AC_DEFINE(LINK_OBSOLETE_RPC)
389 AC_ARG_ENABLE([obsolete-nsl],
390 AC_HELP_STRING([--enable-obsolete-nsl],
391 [build and install the obsolete libnsl library and depending NSS modules]),
392 [build_obsolete_nsl=$enableval],
393 [build_obsolete_nsl=no])
394 AC_SUBST(build_obsolete_nsl)
396 if test "$build_obsolete_nsl" = yes; then
397 AC_DEFINE(LINK_OBSOLETE_NSL)
400 AC_ARG_ENABLE([systemtap],
401 [AS_HELP_STRING([--enable-systemtap],
402 [enable systemtap static probe points @<:@default=no@:>@])],
403 [systemtap=$enableval],
405 if test "x$systemtap" != xno; then
406 AC_CACHE_CHECK([for systemtap static probe support], libc_cv_sdt, [dnl
408 CFLAGS="-std=gnu11 $CFLAGS"
409 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <sys/sdt.h>
410 void foo (int i, void *p)
412 asm ("" STAP_PROBE_ASM (foo, bar, STAP_PROBE_ASM_TEMPLATE (2)) ""
413 :: STAP_PROBE_ASM_OPERANDS (2, i, p));
414 }]])], [libc_cv_sdt=yes], [libc_cv_sdt=no])
415 CFLAGS="$old_CFLAGS"])
416 if test $libc_cv_sdt = yes; then
417 AC_DEFINE([USE_STAP_PROBE])
418 elif test "x$systemtap" != xauto; then
419 AC_MSG_FAILURE([systemtap support needs sys/sdt.h with asm support])
423 AC_ARG_ENABLE([build-nscd],
424 [AS_HELP_STRING([--disable-build-nscd],
425 [disable building and installing the nscd daemon])],
426 [build_nscd=$enableval],
427 [build_nscd=default])
430 # Note the use of $use_nscd is near the bottom of the file.
431 AC_ARG_ENABLE([nscd],
432 [AS_HELP_STRING([--disable-nscd],
433 [library functions will not contact the nscd daemon])],
434 [use_nscd=$enableval],
437 AC_ARG_ENABLE([pt_chown],
438 [AS_HELP_STRING([--enable-pt_chown],
439 [Enable building and installing pt_chown])],
440 [build_pt_chown=$enableval],
442 AC_SUBST(build_pt_chown)
443 if test "$build_pt_chown" = yes; then
444 AC_DEFINE(HAVE_PT_CHOWN)
447 AC_ARG_ENABLE([tunables],
448 [AS_HELP_STRING([--enable-tunables],
449 [Enable tunables support. Known values are 'yes', 'no' and 'valstring'])],
450 [have_tunables=$enableval],
452 AC_SUBST(have_tunables)
453 if test "$have_tunables" = yes; then
454 AC_DEFINE(HAVE_TUNABLES)
457 # The abi-tags file uses a fairly simplistic model for name recognition that
458 # can't distinguish i486-pc-linux-gnu fully from i486-pc-gnu. So we mutate a
459 # $host_os of `gnu*' here to be `gnu-gnu*' just so that it can tell.
460 # This doesn't get used much beyond that, so it's fairly safe.
465 host_os=`echo $host_os | sed -e 's/gnu/gnu-gnu/'`
469 AC_ARG_ENABLE([mathvec],
470 [AS_HELP_STRING([--enable-mathvec],
471 [Enable building and installing mathvec @<:@default depends on architecture@:>@])],
472 [build_mathvec=$enableval],
473 [build_mathvec=notset])
476 AC_HELP_STRING([--enable-cet],
477 [enable Intel Control-flow Enforcement Technology (CET), x86 only]),
478 [enable_cet=$enableval],
481 # We keep the original values in `$config_*' and never modify them, so we
482 # can write them unchanged into config.make. Everything else uses
483 # $machine, $vendor, and $os, and changes them whenever convenient.
484 config_machine=$host_cpu config_vendor=$host_vendor config_os=$host_os
486 # Don't allow vendor == "unknown"
487 test "$config_vendor" = unknown && config_vendor=
488 config_os="`echo $config_os | sed 's/^unknown-//'`"
490 # Some configurations imply other options.
493 # The configure fragment of a port can modify these to supplement
494 # or override the table in the case statement below. No fragment should
495 # ever change the config_* variables, however.
496 machine=$config_machine
497 vendor=$config_vendor
503 AS_HELP_STRING([--with-cpu=CPU], [select code for CPU variant]),
506 yes|'') AC_MSG_ERROR([--with-cpu requires an argument]) ;;
508 *) submachine="$withval" ;;
512 # An preconfigure script can set this when it wants to disable the sanity
516 # A preconfigure script for a system that may or may not use fpu
517 # sysdeps directories sets this to a preprocessor conditional for
518 # whether to use such directories.
521 dnl Let sysdeps/*/preconfigure act here.
522 LIBC_PRECONFIGURE([$srcdir], [for sysdeps])
526 ### By using the undocumented --enable-hacker-mode option for configure
527 ### one can skip this test to make the configuration not fail for unsupported
530 if test -z "$enable_hacker_mode" && test x"$libc_config_ok" != xyes; then
531 case "$machine-$host_os" in
536 *** The GNU C library is currently unavailable for this platform.
537 *** If you are interested in seeing glibc on this platform visit
538 *** the "How to submit a new port" in the wiki:
539 *** https://sourceware.org/glibc/wiki/#Development
540 *** and join the community!])
545 # Set base_machine if not set by a preconfigure fragment.
546 test -n "$base_machine" || base_machine=$machine
547 AC_SUBST(base_machine)
549 # Determine whether to use fpu or nofpu sysdeps directories.
550 AC_CACHE_CHECK([for use of fpu sysdeps directories],
551 libc_cv_with_fp, [dnl
552 cat > conftest.c <<EOF
556 # error "no hardware floating point"
560 if ${CC-cc} $CFLAGS $CPPFLAGS -S conftest.c -o conftest.s \
561 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
565 AC_SUBST(libc_cv_with_fp)
567 AC_CACHE_CHECK(for -fstack-protector, libc_cv_ssp, [dnl
568 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector],
573 AC_CACHE_CHECK(for -fstack-protector-strong, libc_cv_ssp_strong, [dnl
574 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-strong],
575 [libc_cv_ssp_strong=yes],
576 [libc_cv_ssp_strong=no])
579 AC_CACHE_CHECK(for -fstack-protector-all, libc_cv_ssp_all, [dnl
580 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-all],
581 [libc_cv_ssp_all=yes],
582 [libc_cv_ssp_all=no])
587 if test "$libc_cv_ssp" = yes; then
588 no_stack_protector="-fno-stack-protector -DSTACK_PROTECTOR_LEVEL=0"
589 AC_DEFINE(HAVE_CC_NO_STACK_PROTECTOR)
592 if test "$enable_stack_protector" = yes && test "$libc_cv_ssp" = yes; then
593 stack_protector="-fstack-protector"
594 AC_DEFINE(STACK_PROTECTOR_LEVEL, 1)
595 elif test "$enable_stack_protector" = all && test "$libc_cv_ssp_all" = yes; then
596 stack_protector="-fstack-protector-all"
597 AC_DEFINE(STACK_PROTECTOR_LEVEL, 2)
598 elif test "$enable_stack_protector" = strong && test "$libc_cv_ssp_strong" = yes; then
599 stack_protector="-fstack-protector-strong"
600 AC_DEFINE(STACK_PROTECTOR_LEVEL, 3)
602 stack_protector="-fno-stack-protector"
603 AC_DEFINE(STACK_PROTECTOR_LEVEL, 0)
605 AC_SUBST(libc_cv_ssp)
606 AC_SUBST(stack_protector)
607 AC_SUBST(no_stack_protector)
609 if test -n "$stack_protector"; then
610 dnl Don't run configure tests with stack-protection on, to avoid problems with
612 no_ssp=-fno-stack-protector
616 if test "$enable_stack_protector" != no; then
617 AC_MSG_ERROR([--enable-stack-protector=$enable_stack_protector specified, but specified level of stack protection is not supported by the compiler.])
621 # For the multi-arch option we need support in the assembler & linker.
622 AC_CACHE_CHECK([for assembler and linker STT_GNU_IFUNC support],
623 libc_cv_ld_gnu_indirect_function, [dnl
624 cat > conftest.S <<EOF
625 .type foo,%gnu_indirect_function
638 libc_cv_ld_gnu_indirect_function=no
639 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
640 -nostartfiles -nostdlib $no_ssp \
641 -o conftest conftest.S 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
642 # Do a link to see if the backend supports IFUNC relocs.
643 $READELF -r conftest 1>&AS_MESSAGE_LOG_FD
644 LC_ALL=C $READELF -r conftest | grep 'no relocations' >/dev/null || {
645 libc_cv_ld_gnu_indirect_function=yes
650 # Check if gcc supports attribute ifunc as it is used in libc_ifunc macro.
651 AC_CACHE_CHECK([for gcc attribute ifunc support],
652 libc_cv_gcc_indirect_function, [dnl
653 cat > conftest.c <<EOF
654 extern int func (int);
655 int used_func (int a)
659 static void *resolver ()
663 extern __typeof (func) func __attribute__ ((ifunc ("resolver")));
665 libc_cv_gcc_indirect_function=no
666 if ${CC-cc} -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD \
667 2>&AS_MESSAGE_LOG_FD ; then
668 if $READELF -s conftest.o | grep IFUNC >/dev/null 2>&AS_MESSAGE_LOG_FD; then
669 libc_cv_gcc_indirect_function=yes
674 # Check if linker supports textrel relocation with ifunc (used on elf/tests).
675 # Note that it relies on libc_cv_ld_gnu_indirect_function test above.
676 AC_CACHE_CHECK([whether the linker supports textrels along with ifunc],
677 libc_cv_textrel_ifunc, [dnl
678 cat > conftest.S <<EOF
679 .type foo,%gnu_indirect_function
700 libc_cv_textrel_ifunc=no
701 if test $libc_cv_ld_gnu_indirect_function = yes; then
702 if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp -pie -o conftest conftest.S); then
703 libc_cv_textrel_ifunc=yes
707 AC_SUBST(libc_cv_textrel_ifunc)
709 # Check if gcc warns about alias for function with incompatible types.
710 AC_CACHE_CHECK([if compiler warns about alias for function with incompatible types],
711 libc_cv_gcc_incompatible_alias, [dnl
712 cat > conftest.c <<EOF
713 int __redirect_foo (const void *s, int c);
715 __typeof (__redirect_foo) *foo_impl (void) __asm__ ("foo");
716 __typeof (__redirect_foo) *foo_impl (void)
721 extern __typeof (__redirect_foo) foo_alias __attribute__ ((alias ("foo")));
723 libc_cv_gcc_incompatible_alias=yes
724 if ${CC-cc} -Werror -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
725 libc_cv_gcc_incompatible_alias=no
729 if test x"$libc_cv_ld_gnu_indirect_function" != xyes; then
730 if test x"$multi_arch" = xyes; then
731 AC_MSG_ERROR([--enable-multi-arch support requires assembler and linker support])
736 if test x"$libc_cv_gcc_indirect_function" != xyes; then
737 # GCC 8+ emits a warning for alias with incompatible types and it might
738 # fail to build ifunc resolvers aliases to either weak or internal
739 # symbols. Disables multiarch build in this case.
740 if test x"$libc_cv_gcc_incompatible_alias" == xyes; then
741 AC_MSG_WARN([gcc emits a warning for alias between functions of incompatible types])
742 if test x"$multi_arch" = xyes; then
743 AC_MSG_ERROR([--enable-multi-arch support requires a gcc with gnu-indirect-function support])
745 AC_MSG_WARN([Multi-arch is disabled.])
747 elif test x"$multi_arch" = xyes; then
748 AC_MSG_WARN([--enable-multi-arch support recommends a gcc with gnu-indirect-function support.
749 Please use a gcc which supports it by default or configure gcc with --enable-gnu-indirect-function])
753 if test x"$multi_arch" != xno; then
754 multi_arch_d=/multiarch
757 # Compute the list of sysdep directories for this configuration.
758 # This can take a while to compute.
759 sysdep_dir=$srcdir/sysdeps
760 AC_MSG_CHECKING(sysdep dirs)
761 dnl We need to use [ and ] for other purposes for a while now.
763 # Make sco3.2v4 become sco3.2.4 and sunos4.1.1_U1 become sunos4.1.1.U1.
764 os="`echo $os | sed 's/\([0-9A-Z]\)[v_]\([0-9A-Z]\)/\1.\2/g'`"
766 test "x$base_os" != x || case "$os" in
773 # For sunos4.1.1, try sunos4.1.1, then sunos4.1, then sunos4, then sunos.
776 while o=`echo $tail | sed 's/\.[^.]*$//'`; test $o != $tail; do
780 o=`echo $tail | sed 's/[0-9]*$//'`
781 if test $o != $tail; then
784 # For linux-gnu, try linux-gnu, then linux.
785 o=`echo $tail | sed 's/-.*$//'`
786 if test $o != $tail; then
790 # For unix/sysv/sysv4, try unix/sysv/sysv4, then unix/sysv, then unix.
793 while b=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$b"; do
799 # For sparc/sparc32, try sparc/sparc32 and then sparc.
801 tail=$machine${submachine:+/$submachine}
802 while m=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$m"; do
804 # Prepend the machine's FPU directory unless --without-fp.
805 if test "$libc_cv_with_fp" = yes; then
810 # For each machine term, try it with and then without /multiarch.
811 for try_fpu in $maybe_fpu ''; do
812 for try_multi in $multi_arch_d ''; do
813 mach="$mach /$1$try_fpu$try_multi"
819 dnl We are done with glob and regexp uses of [ and ]; return to autoconf.
822 # Find what sysdep directories exist.
824 for b in $base ''; do
825 for m0 in $mach ''; do
826 for v in /$vendor ''; do
827 test "$v" = / && continue
828 for o in /$ostry ''; do
829 test "$o" = / && continue
830 for m in $mach ''; do
831 try_suffix="$m0$b$v$o$m"
832 if test -n "$try_suffix"; then
833 try_srcdir="${srcdir}/"
834 try="sysdeps$try_suffix"
835 test -n "$enable_debug_configure" &&
836 echo "$0 [DEBUG]: try $try" >&2
837 if test -d "$try_srcdir$try"; then
838 sysnames="$sysnames $try"
839 { test -n "$o" || test -n "$b"; } && os_used=t
840 { test -n "$m" || test -n "$m0"; } && machine_used=t
842 x*/$submachine) submachine_used=t ;;
852 # If the assembler supports gnu_indirect_function symbol type and the
853 # architecture supports multi-arch, we enable multi-arch by default.
858 test x"$multi_arch" = xdefault && multi_arch=no
861 if test x"$multi_arch" != xno; then
862 AC_DEFINE(USE_MULTIARCH)
866 if test -z "$os_used" && test "$os" != none; then
867 AC_MSG_ERROR(Operating system $os is not supported.)
869 if test -z "$machine_used" && test "$machine" != none; then
870 AC_MSG_ERROR(The $machine is not supported.)
872 if test -z "$submachine_used" && test -n "$submachine"; then
873 AC_MSG_ERROR(The $submachine subspecies of $host_cpu is not supported.)
877 # We have now validated the configuration.
879 # Expand the list of system names into a full list of directories
880 # from each element's parent name and Implies file (if present).
883 while test $# -gt 0; do
887 case " $names " in *" $name "*)
888 # Already in the list.
892 # Report each name as we discover it, so there is no long pause in output.
893 echo $ECHO_N "$name $ECHO_C" >&AS_MESSAGE_FD
895 name_base=`echo $name | sed -e 's@\(.*sysdeps\)/.*@\1@'`
899 *) xsrcdir=$srcdir/ ;;
901 test -n "$enable_debug_configure" &&
902 echo "[DEBUG]: name/Implies $xsrcdir$name/Implies" >&2
904 for implies_file in Implies Implies-before Implies-after; do
905 implies_type=`echo $implies_file | sed s/-/_/`
906 eval ${implies_type}=
907 if test -f $xsrcdir$name/$implies_file; then
908 # Collect more names from the `Implies' file (removing comments).
909 implied_candidate="`sed 's/#.*$//' < $xsrcdir$name/$implies_file`"
910 for x in $implied_candidate; do
912 if test -d $xsrcdir$name_base/$x; then
913 eval "${implies_type}=\"\$${implies_type} \$name_base/\$x\""
918 test -n "$enable_debug_configure" &&
919 echo "[DEBUG]: $name $implies_file $x try() {$try_srcdir}$try" >&2
920 if test $try != $xsrcdir$name_base/$x && test -d $try_srcdir$try;
922 eval "${implies_type}=\"\$${implies_type} \$try\""
925 if test $found = no; then
926 AC_MSG_WARN($name/$implies_file specifies nonexistent $x)
932 # Add NAME to the list of names.
935 # Find the parent of NAME, using the empty string if it has none.
937 parent="`echo $name | sed -n -e 's=/[^/]*$==' -e '/sysdeps$/q' -e p`"
940 test -n "$enable_debug_configure" &&
941 echo "[DEBUG]: $name Implies='$Implies' rest='$*' parent='$parent' \
942 Implies_before='$Implies_before' Implies_after='$Implies_after'" >&2
944 # Add the names implied by NAME, and NAME's parent (if it has one), to
945 # the list of names to be processed (the argument list). We prepend the
946 # implied names to the list and append the parent. We want implied
947 # directories to come before further directories inferred from the
948 # configuration components; this ensures that for sysv4, unix/common
949 # (implied by unix/sysv/sysv4) comes before unix/sysv (in ostry (here $*)
951 sysnames="`echo $Implies $* $Implies_before $parent $Implies_after`"
952 test -n "$sysnames" && set $sysnames
955 # Add the default directories.
956 default_sysnames="sysdeps/generic"
957 sysnames="$names $default_sysnames"
959 # The other names were emitted during the scan.
960 AC_MSG_RESULT($default_sysnames)
966 if test "$INSTALL" = "${srcdir}/scripts/install-sh -c"; then
967 # The makefiles need to use a different form to find it in $srcdir.
968 INSTALL='\$(..)./scripts/install-sh -c'
974 # Accept binutils 2.25 or newer.
975 AC_CHECK_PROG_VER(AS, $AS, --version,
976 [GNU assembler.* \([0-9]*\.[0-9.]*\)],
977 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
978 AS=: critic_missing="$critic_missing as")
980 if test -n "`$LD --version | sed -n 's/^GNU \(gold\).*$/\1/p'`"; then
981 # Accept gold 1.14 or higher
982 AC_CHECK_PROG_VER(LD, $LD, --version,
983 [GNU gold.* \([0-9][0-9]*\.[0-9.]*\)],
984 [1.1[4-9]*|1.[2-9][0-9]*|1.1[0-9][0-9]*|[2-9].*|[1-9][0-9]*],
985 LD=: critic_missing="$critic_missing GNU gold")
987 AC_CHECK_PROG_VER(LD, $LD, --version,
988 [GNU ld.* \([0-9][0-9]*\.[0-9.]*\)],
989 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
990 LD=: critic_missing="$critic_missing GNU ld")
993 # These programs are version sensitive.
995 AC_CHECK_PROG_VER(MAKE, gnumake gmake make, --version,
996 [GNU Make[^0-9]*\([0-9][0-9.]*\)],
997 [[4-9].* | [1-9][0-9]*], critic_missing="$critic_missing make")
999 AC_CHECK_PROG_VER(MSGFMT, gnumsgfmt gmsgfmt msgfmt, --version,
1000 [GNU gettext.* \([0-9]*\.[0-9.]*\)],
1001 [0.10.3[6-9]* | 0.10.[4-9][0-9]* | 0.1[1-9]* | 0.[2-9][0-9]* | [1-9].*],
1002 MSGFMT=: aux_missing="$aux_missing msgfmt")
1003 AC_CHECK_PROG_VER(MAKEINFO, makeinfo, --version,
1004 [GNU texinfo.* \([0-9][0-9.]*\)],
1005 [4.[7-9]*|4.[1-9][0-9]*|[5-9].*],
1006 MAKEINFO=: aux_missing="$aux_missing makeinfo")
1007 AC_CHECK_PROG_VER(SED, sed, --version,
1008 [GNU sed[^0-9]* \([0-9]*\.[0-9.]*\)],
1009 [3.0[2-9]*|3.[1-9]*|[4-9]*],
1010 SED=: aux_missing="$aux_missing sed")
1011 AC_CHECK_PROG_VER(AWK, gawk, --version,
1012 [GNU Awk[^0-9]*\([0-9][0-9.]*\)],
1013 [3.1.[2-9]*|3.[2-9]*|[4-9]*], critic_missing="$critic_missing gawk")
1014 AC_CHECK_PROG_VER(BISON, bison, --version,
1015 [bison (GNU Bison) \([0-9]*\.[0-9.]*\)],
1016 [2.7*|[3-9].*|[1-9][0-9]*], critic_missing="$critic_missing bison")
1018 AC_CACHE_CHECK([if $CC is sufficient to build libc], libc_cv_compiler_ok, [
1019 AC_TRY_COMPILE([], [
1020 #if !defined __GNUC__ || __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 9)
1021 #error insufficient compiler
1023 [libc_cv_compiler_ok=yes],
1024 [libc_cv_compiler_ok=no])])
1025 AS_IF([test $libc_cv_compiler_ok != yes],
1026 [critic_missing="$critic_missing compiler"])
1028 AC_CHECK_TOOL(NM, nm, false)
1030 if test "x$maintainer" = "xyes"; then
1031 AC_CHECK_PROGS(AUTOCONF, autoconf, no)
1032 case "x$AUTOCONF" in
1033 xno|x|x:) AUTOCONF=no ;;
1036 whether $AUTOCONF${ACFLAGS:+ }$ACFLAGS works, libc_cv_autoconf_works, [dnl
1037 if (cd $srcdir; $AUTOCONF $ACFLAGS configure.ac > /dev/null 2>&1); then
1038 libc_cv_autoconf_works=yes
1040 libc_cv_autoconf_works=no
1042 test $libc_cv_autoconf_works = yes || AUTOCONF=no
1045 if test "x$AUTOCONF" = xno; then
1046 aux_missing="$aux_missing autoconf"
1052 # Check for python3 if available, or else python.
1053 AC_CHECK_PROGS(PYTHON_PROG, python3 python,no)
1054 case "x$PYTHON_PROG" in
1055 xno|x|x:) PYTHON_PROG=no ;;
1059 if test "x$PYTHON_PROG" = xno; then
1060 aux_missing="$aux_missing python"
1062 PYTHON="$PYTHON_PROG -B"
1066 test -n "$critic_missing" && AC_MSG_ERROR([
1067 *** These critical programs are missing or too old:$critic_missing
1068 *** Check the INSTALL file for required versions.])
1070 test -n "$aux_missing" && AC_MSG_WARN([
1071 *** These auxiliary programs are missing or incompatible versions:$aux_missing
1072 *** some features or tests will be disabled.
1073 *** Check the INSTALL file for required versions.])
1075 # if using special system headers, find out the compiler's sekrit
1076 # header directory and add that to the list. NOTE: Only does the right
1077 # thing on a system that doesn't need fixincludes. (Not presently a problem.)
1078 if test -n "$sysheaders"; then
1079 SYSINCLUDES=-nostdinc
1080 for d in include include-fixed; do
1081 i=`$CC -print-file-name="$d"` && test "x$i" != x && test "x$i" != "x$d" &&
1082 SYSINCLUDES="$SYSINCLUDES -isystem $i"
1084 SYSINCLUDES="$SYSINCLUDES \
1085 -isystem `echo $sysheaders | sed 's/:/ -isystem /g'`"
1086 if test -n "$CXX"; then
1088 for cxxheaders in `$CXX -v -S -x c++ /dev/null -o /dev/null 2>&1 \
1089 | sed -n -e '1,/#include/d' -e 's/^ \(\/.*\/[cg]++\)/\1/p'`; do
1090 test "x$cxxheaders" != x &&
1091 CXX_SYSINCLUDES="$CXX_SYSINCLUDES -isystem $cxxheaders"
1095 AC_SUBST(SYSINCLUDES)
1096 AC_SUBST(CXX_SYSINCLUDES)
1098 # Obtain some C++ header file paths. This is used to make a local
1099 # copy of those headers in Makerules.
1100 if test -n "$CXX"; then
1101 find_cxx_header () {
1102 echo "#include <$1>" | $CXX -M -MP -x c++ - 2>/dev/null \
1103 | sed -n "\,$1:,{s/:\$//;p}"
1105 CXX_CSTDLIB_HEADER="$(find_cxx_header cstdlib)"
1106 CXX_CMATH_HEADER="$(find_cxx_header cmath)"
1107 CXX_BITS_STD_ABS_H="$(find_cxx_header bits/std_abs.h)"
1109 AC_SUBST(CXX_CSTDLIB_HEADER)
1110 AC_SUBST(CXX_CMATH_HEADER)
1111 AC_SUBST(CXX_BITS_STD_ABS_H)
1113 # Test if LD_LIBRARY_PATH contains the notation for the current directory
1114 # since this would lead to problems installing/building glibc.
1115 # LD_LIBRARY_PATH contains the current directory if one of the following
1117 # - one of the terminals (":" and ";") is the first or last sign
1118 # - two terminals occur directly after each other
1119 # - the path contains an element with a dot in it
1120 AC_MSG_CHECKING(LD_LIBRARY_PATH variable)
1122 case ${LD_LIBRARY_PATH} in
1123 [:\;]* | *[:\;] | *[:\;][:\;]* | *[:\;]. | .[:\;]*| . | *[:\;].[:\;]* )
1124 ld_library_path_setting="contains current directory"
1127 ld_library_path_setting="ok"
1131 AC_MSG_RESULT($ld_library_path_setting)
1132 if test "$ld_library_path_setting" != "ok"; then
1134 *** LD_LIBRARY_PATH shouldn't contain the current directory when
1135 *** building glibc. Please change the environment variable
1136 *** and run configure again.])
1139 AC_PATH_PROG(BASH_SHELL, bash, no)
1141 AC_PATH_PROG(PERL, perl, no)
1142 if test "$PERL" != no &&
1143 (eval `$PERL -V:apiversion`; test `expr "$apiversion" \< 5` -ne 0); then
1146 AC_PATH_PROG(INSTALL_INFO, install-info, no,
1147 $PATH:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin)
1149 AC_CACHE_CHECK(for .set assembler directive, libc_cv_asm_set_directive, [dnl
1150 cat > conftest.s <<EOF
1153 .set glibc_conftest_frobozz,foo
1154 .globl glibc_conftest_frobozz
1156 # The alpha-dec-osf1 assembler gives only a warning for `.set'
1157 # (but it doesn't work), so we must do a linking check to be sure.
1158 cat > conftest1.c <<\EOF
1159 extern int glibc_conftest_frobozz;
1160 void _start() { glibc_conftest_frobozz = 1; }
1162 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
1163 -nostartfiles -nostdlib $no_ssp \
1164 -o conftest conftest.s conftest1.c 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
1165 libc_cv_asm_set_directive=yes
1167 libc_cv_asm_set_directive=no
1170 if test $libc_cv_asm_set_directive = yes; then
1171 AC_DEFINE(HAVE_ASM_SET_DIRECTIVE)
1174 AC_CACHE_CHECK(linker support for protected data symbol,
1175 libc_cv_protected_data,
1176 [cat > conftest.c <<EOF
1177 int bar __attribute__ ((visibility ("protected"))) = 1;
1179 libc_cv_protected_data=no
1180 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -o conftest.so); then
1181 cat > conftest.c <<EOF
1183 int main (void) { return bar; }
1185 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp conftest.c -o conftest conftest.so); then
1186 libc_cv_protected_data=yes
1191 AC_SUBST(libc_cv_protected_data)
1193 AC_CACHE_CHECK(linker support for INSERT in linker script,
1195 [cat > conftest.c <<EOF
1196 const int __attribute__ ((section(".bar"))) bar = 0x12345678;
1197 int test (void) { return bar; }
1199 cat > conftest.t <<EOF
1204 INSERT AFTER .rela.dyn;
1207 if AC_TRY_COMMAND([${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -Wl,-T,conftest.t -o conftest.so]); then
1212 AC_SUBST(libc_cv_insert)
1214 AC_CACHE_CHECK(for broken __attribute__((alias())),
1215 libc_cv_broken_alias_attribute,
1216 [cat > conftest.c <<EOF
1217 extern int foo (int x) __asm ("xyzzy");
1218 int bar (int x) { return x; }
1219 extern __typeof (bar) foo __attribute ((weak, alias ("bar")));
1221 extern __typeof (dfoo) dfoo __asm ("abccb");
1224 libc_cv_broken_alias_attribute=yes
1225 if AC_TRY_COMMAND(${CC-cc} -Werror -S conftest.c -o conftest.s 1>&AS_MESSAGE_LOG_FD); then
1226 if grep 'xyzzy' conftest.s >/dev/null &&
1227 grep 'abccb' conftest.s >/dev/null; then
1228 libc_cv_broken_alias_attribute=no
1231 rm -f conftest.c conftest.s
1233 if test $libc_cv_broken_alias_attribute = yes; then
1234 AC_MSG_ERROR(working alias attribute support required)
1237 AC_CACHE_CHECK(whether to put _rtld_local into .sdata section,
1238 libc_cv_have_sdata_section,
1239 [echo "int i;" > conftest.c
1240 libc_cv_have_sdata_section=no
1241 if ${CC-cc} $LDFLAGS -fPIC -shared -Wl,--verbose conftest.c -o conftest.so 2>&1 \
1242 | grep '\.sdata' >/dev/null; then
1243 libc_cv_have_sdata_section=yes
1245 rm -f conftest.c conftest.so
1247 if test $libc_cv_have_sdata_section = yes; then
1248 AC_DEFINE(HAVE_SDATA_SECTION)
1251 AC_CACHE_CHECK(whether to use .ctors/.dtors header and trailer,
1252 libc_cv_ctors_header, [dnl
1253 libc_cv_ctors_header=yes
1254 LIBC_TRY_LINK_STATIC([
1255 __attribute__ ((constructor)) void ctor (void) { asm (""); }
1256 __attribute__ ((destructor)) void dtor (void) { asm (""); }
1259 AS_IF([$READELF -WS conftest$ac_exeext | $AWK '
1260 { gsub(/\@<:@ */, "@<:@") }
1261 $2 == ".ctors" || $2 == ".dtors" {
1262 size = strtonum("0x" $6)
1263 align = strtonum("0x" $NF)
1265 stub@<:@$2@:>@ = size == align * 2
1268 ctors_ok = !seen@<:@".ctors"@:>@ || stub@<:@".ctors"@:>@
1269 dtors_ok = !seen@<:@".dtors"@:>@ || stub@<:@".dtors"@:>@
1270 exit ((ctors_ok && dtors_ok) ? 0 : 1)
1272 '], [libc_cv_ctors_header=no])
1274 AC_MSG_ERROR([missing __attribute__ ((constructor)) support??])
1277 if test $libc_cv_ctors_header = no; then
1278 AC_DEFINE(NO_CTORS_DTORS_SECTIONS)
1281 AC_CACHE_CHECK(for libunwind-support in compiler,
1282 libc_cv_cc_with_libunwind, [
1283 cat > conftest.c <<EOF
1284 int main (void) { return 0; }
1286 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -static -o conftest \
1287 conftest.c -v 2>&1 >/dev/null | grep ' -lunwind ' >/dev/null; then
1288 libc_cv_cc_with_libunwind=yes
1290 libc_cv_cc_with_libunwind=no
1293 AC_SUBST(libc_cv_cc_with_libunwind)
1294 if test $libc_cv_cc_with_libunwind = yes; then
1295 AC_DEFINE(HAVE_CC_WITH_LIBUNWIND)
1299 AC_CACHE_CHECK(whether --noexecstack is desirable for .S files,
1300 libc_cv_as_noexecstack, [dnl
1301 cat > conftest.c <<EOF
1304 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS
1305 -S -o conftest.s conftest.c 1>&AS_MESSAGE_LOG_FD]) \
1306 && grep .note.GNU-stack conftest.s >/dev/null \
1307 && AC_TRY_COMMAND([${CC-cc} $ASFLAGS -Wa,--noexecstack
1308 -c -o conftest.o conftest.s 1>&AS_MESSAGE_LOG_FD])
1310 libc_cv_as_noexecstack=yes
1312 libc_cv_as_noexecstack=no
1315 if test $libc_cv_as_noexecstack = yes; then
1316 ASFLAGS_config="$ASFLAGS_config -Wa,--noexecstack"
1318 AC_SUBST(ASFLAGS_config)
1320 AC_CACHE_CHECK(for -z combreloc,
1321 libc_cv_z_combreloc, [dnl
1322 cat > conftest.c <<EOF
1323 extern int bar (int);
1325 int foo (void) { return bar (mumble); }
1327 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1328 -fPIC -shared $no_ssp -o conftest.so conftest.c
1329 -nostdlib -nostartfiles
1330 -Wl,-z,combreloc 1>&AS_MESSAGE_LOG_FD])
1332 dnl The following test is a bit weak. We must use a tool which can test
1333 dnl cross-platform since the gcc used can be a cross compiler. Without
1334 dnl introducing new options this is not easily doable. Instead use a tool
1335 dnl which always is cross-platform: readelf. To detect whether -z combreloc
1336 dnl look for a section named .rel.dyn or .rela.dyn.
1337 if $READELF -S conftest.so | grep -E '.rela?.dyn' > /dev/null; then
1338 libc_cv_z_combreloc=yes
1340 libc_cv_z_combreloc=no
1343 libc_cv_z_combreloc=no
1346 if test "$libc_cv_z_combreloc" = yes; then
1347 AC_DEFINE(HAVE_Z_COMBRELOC)
1349 AC_SUBST(libc_cv_z_combreloc)
1351 LIBC_LINKER_FEATURE([-z execstack], [-Wl,-z,execstack],
1352 [libc_cv_z_execstack=yes], [libc_cv_z_execstack=no])
1353 AC_SUBST(libc_cv_z_execstack)
1355 LIBC_LINKER_FEATURE([--no-dynamic-linker],
1356 [-Wl,--no-dynamic-linker],
1357 [libc_cv_no_dynamic_linker=yes],
1358 [libc_cv_no_dynamic_linker=no])
1359 LIBC_CONFIG_VAR([have-no-dynamic-linker], [$libc_cv_no_dynamic_linker])
1361 AC_CACHE_CHECK(for -static-pie, libc_cv_static_pie, [dnl
1362 LIBC_TRY_CC_OPTION([-static-pie],
1363 [libc_cv_static_pie=yes],
1364 [libc_cv_static_pie=no])
1366 LIBC_CONFIG_VAR([have-static-pie], [$libc_cv_static_pie])
1368 AC_CACHE_CHECK(for -fpie, libc_cv_fpie, [dnl
1369 LIBC_TRY_CC_OPTION([-fpie], [libc_cv_fpie=yes], [libc_cv_fpie=no])
1372 AC_SUBST(libc_cv_fpie)
1374 AC_CACHE_CHECK(for --hash-style option,
1375 libc_cv_hashstyle, [dnl
1376 cat > conftest.c <<EOF
1377 int _start (void) { return 42; }
1379 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp
1380 -fPIC -shared -o conftest.so conftest.c
1381 -Wl,--hash-style=both -nostdlib 1>&AS_MESSAGE_LOG_FD])
1383 libc_cv_hashstyle=yes
1385 libc_cv_hashstyle=no
1388 AC_SUBST(libc_cv_hashstyle)
1390 # The linker's default -shared behavior is good enough if it
1391 # does these things that our custom linker scripts ensure that
1392 # all allocated NOTE sections come first.
1393 if test "$use_default_link" = default; then
1394 AC_CACHE_CHECK([for sufficient default -shared layout],
1395 libc_cv_use_default_link, [dnl
1396 libc_cv_use_default_link=no
1397 cat > conftest.s <<\EOF
1398 .section .note.a,"a",%note
1403 .section .note.b,"a",%note
1409 if AC_TRY_COMMAND([dnl
1410 ${CC-cc} $ASFLAGS -shared -o conftest.so conftest.s 1>&AS_MESSAGE_LOG_FD]) &&
1411 ac_try=`$READELF -S conftest.so | sed -n \
1413 s/^ *\[ *[1-9][0-9]*\] *\([^ ][^ ]*\) *\([^ ][^ ]*\) .*$/\2 \1/
1419 libc_seen_a=no libc_seen_b=no
1421 while test $# -ge 2 -a "$1" = NOTE; do
1423 .note.a) libc_seen_a=yes ;;
1424 .note.b) libc_seen_b=yes ;;
1428 case "$libc_seen_a$libc_seen_b" in
1430 libc_cv_use_default_link=yes
1433 echo >&AS_MESSAGE_LOG_FD "\
1434 $libc_seen_a$libc_seen_b from:
1440 use_default_link=$libc_cv_use_default_link
1443 AC_CACHE_CHECK(for GLOB_DAT reloc,
1444 libc_cv_has_glob_dat, [dnl
1445 cat > conftest.c <<EOF
1447 int foo (void) { return mumble; }
1449 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1450 -fPIC -shared -o conftest.so conftest.c
1451 -nostdlib -nostartfiles $no_ssp
1452 1>&AS_MESSAGE_LOG_FD])
1454 dnl look for GLOB_DAT relocation.
1455 if $READELF -rW conftest.so | grep '_GLOB_DAT' > /dev/null; then
1456 libc_cv_has_glob_dat=yes
1458 libc_cv_has_glob_dat=no
1461 libc_cv_has_glob_dat=no
1464 AC_SUBST(libc_cv_has_glob_dat)
1466 AC_CACHE_CHECK(linker output format, libc_cv_output_format, [dnl
1467 if libc_cv_output_format=`
1468 ${CC-cc} -nostartfiles -nostdlib $no_ssp -Wl,--print-output-format 2>&AS_MESSAGE_LOG_FD`
1472 libc_cv_output_format=
1474 test -n "$libc_cv_output_format" || libc_cv_output_format=unknown])
1475 AC_SUBST(libc_cv_output_format)
1477 AC_CACHE_CHECK(for -fno-toplevel-reorder -fno-section-anchors, libc_cv_fno_toplevel_reorder, [dnl
1478 cat > conftest.c <<EOF
1481 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fno-toplevel-reorder -fno-section-anchors
1482 conftest.c 1>&AS_MESSAGE_LOG_FD])
1484 libc_cv_fno_toplevel_reorder=yes
1486 libc_cv_fno_toplevel_reorder=no
1489 if test $libc_cv_fno_toplevel_reorder = yes; then
1490 fno_unit_at_a_time="-fno-toplevel-reorder -fno-section-anchors"
1492 fno_unit_at_a_time=-fno-unit-at-a-time
1494 AC_SUBST(fno_unit_at_a_time)
1496 AC_CACHE_CHECK([for -mtls-dialect=gnu2], libc_cv_mtls_dialect_gnu2,
1498 cat > conftest.c <<EOF
1505 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fPIC -mtls-dialect=gnu2
1506 conftest.c 1>&AS_MESSAGE_LOG_FD])
1508 libc_cv_mtls_dialect_gnu2=yes
1510 libc_cv_mtls_dialect_gnu2=no
1513 AC_SUBST(libc_cv_mtls_dialect_gnu2)
1514 LIBC_CONFIG_VAR([have-mtls-dialect-gnu2], [$libc_cv_mtls_dialect_gnu2])
1516 AC_CACHE_CHECK(whether cc puts quotes around section names,
1517 libc_cv_have_section_quotes,
1518 [cat > conftest.c <<EOF
1519 static const int foo
1520 __attribute__ ((section ("bar"))) = 1;
1522 if ${CC-cc} -S conftest.c -o conftest.s; then
1523 if grep '\.section.*"bar"' conftest.s >/dev/null; then
1524 libc_cv_have_section_quotes=yes
1526 libc_cv_have_section_quotes=no
1529 libc_cv_have_section_quotes=unknown
1531 rm -f conftest.{c,s}
1533 if test $libc_cv_have_section_quotes = yes; then
1534 AC_DEFINE(HAVE_SECTION_QUOTES)
1537 AC_CACHE_CHECK(for __builtin_memset, libc_cv_gcc_builtin_memset, [dnl
1538 cat > conftest.c <<\EOF
1541 __builtin_memset (x, 0, 1000);
1545 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "memset" > /dev/null]);
1547 libc_cv_gcc_builtin_memset=no
1549 libc_cv_gcc_builtin_memset=yes
1552 if test "$libc_cv_gcc_builtin_memset" = yes ; then
1553 AC_DEFINE(HAVE_BUILTIN_MEMSET)
1556 AC_CACHE_CHECK(for redirection of built-in functions, libc_cv_gcc_builtin_redirection, [dnl
1557 cat > conftest.c <<\EOF
1558 extern char *strstr (const char *, const char *) __asm ("my_strstr");
1559 char *foo (const char *a, const char *b)
1561 return __builtin_strstr (a, b);
1565 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "my_strstr" > /dev/null]);
1567 libc_cv_gcc_builtin_redirection=yes
1569 libc_cv_gcc_builtin_redirection=no
1572 if test "$libc_cv_gcc_builtin_redirection" = no; then
1573 AC_MSG_ERROR([support for the symbol redirection needed])
1576 dnl Determine how to disable generation of FMA instructions.
1577 AC_CACHE_CHECK([for compiler option to disable generation of FMA instructions],
1578 libc_cv_cc_nofma, [dnl
1580 for opt in -ffp-contract=off -mno-fused-madd; do
1581 LIBC_TRY_CC_OPTION([$opt], [libc_cv_cc_nofma=$opt; break])
1583 AC_SUBST(libc_cv_cc_nofma)
1585 if test -n "$submachine"; then
1586 AC_CACHE_CHECK([for compiler option for CPU variant],
1587 libc_cv_cc_submachine, [dnl
1588 libc_cv_cc_submachine=no
1589 for opt in "-march=$submachine" "-mcpu=$submachine"; do
1590 LIBC_TRY_CC_OPTION([$opt], [
1591 libc_cv_cc_submachine="$opt"
1594 if test "x$libc_cv_cc_submachine" = xno; then
1595 AC_MSG_ERROR([${CC-cc} does not support $submachine])
1598 AC_SUBST(libc_cv_cc_submachine)
1600 AC_CACHE_CHECK(if $CC accepts -fno-tree-loop-distribute-patterns with \
1601 __attribute__ ((__optimize__)), libc_cv_cc_loop_to_function, [dnl
1602 cat > conftest.c <<EOF
1604 __attribute__ ((__optimize__ ("-fno-tree-loop-distribute-patterns")))
1607 libc_cv_cc_loop_to_function=no
1608 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -c conftest.c])
1610 libc_cv_cc_loop_to_function=yes
1613 if test $libc_cv_cc_loop_to_function = yes; then
1614 AC_DEFINE(HAVE_CC_INHIBIT_LOOP_TO_LIBCALL)
1616 AC_SUBST(libc_cv_cc_loop_to_function)
1618 dnl Check whether we have the gd library available.
1619 AC_MSG_CHECKING(for libgd)
1620 if test "$with_gd" != "no"; then
1621 old_CFLAGS="$CFLAGS"
1622 CFLAGS="$CFLAGS $libgd_include"
1623 old_LDFLAGS="$LDFLAGS"
1624 LDFLAGS="$LDFLAGS $libgd_ldflags"
1626 LIBS="$LIBS -lgd -lpng -lz -lm"
1627 AC_TRY_LINK([#include <gd.h>], [gdImagePng (0, 0)], LIBGD=yes, LIBGD=no)
1628 CFLAGS="$old_CFLAGS"
1629 LDFLAGS="$old_LDFLAGS"
1634 AC_MSG_RESULT($LIBGD)
1638 if test x$with_selinux = xno ; then
1641 # See if we have the SELinux library
1642 AC_CHECK_LIB(selinux, is_selinux_enabled,
1643 have_selinux=yes, have_selinux=no)
1644 if test x$with_selinux = xyes ; then
1645 if test x$have_selinux = xno ; then
1646 AC_MSG_ERROR([SELinux explicitly required, but SELinux library not found])
1650 # Check if we're building with SELinux support.
1651 if test "x$have_selinux" = xyes; then
1652 AC_DEFINE(HAVE_SELINUX, 1, [SELinux support])
1654 # See if we have the libaudit library
1655 AC_CHECK_LIB(audit, audit_log_user_avc_message,
1656 have_libaudit=yes, have_libaudit=no)
1657 if test "x$have_libaudit" = xyes; then
1658 AC_DEFINE(HAVE_LIBAUDIT, 1, [SELinux libaudit support])
1660 AC_SUBST(have_libaudit)
1662 # See if we have the libcap library
1663 AC_CHECK_LIB(cap, cap_init, have_libcap=yes, have_libcap=no)
1664 if test "x$have_libcap" = xyes; then
1665 AC_DEFINE(HAVE_LIBCAP, 1, [SELinux libcap support])
1667 AC_SUBST(have_libcap)
1669 AC_SUBST(have_selinux)
1672 dnl Check for silly hacked compilers predefining _FORTIFY_SOURCE.
1673 dnl Since we are building the implementations of the fortified functions here,
1674 dnl having the macro defined interacts very badly.
1675 AC_CACHE_CHECK([for _FORTIFY_SOURCE predefine], libc_cv_predef_fortify_source,
1676 [AC_TRY_COMPILE([], [
1677 #ifdef _FORTIFY_SOURCE
1680 [libc_cv_predef_fortify_source=no],
1681 [libc_cv_predef_fortify_source=yes])])
1682 if test $libc_cv_predef_fortify_source = yes; then
1683 CPPUNDEFS="${CPPUNDEFS:+$CPPUNDEFS }-U_FORTIFY_SOURCE"
1687 # Some linkers on some architectures support __ehdr_start but with
1688 # bugs. Make sure usage of it does not create relocations in the
1689 # output (as the linker should resolve them all for us).
1690 AC_CACHE_CHECK([whether the linker provides working __ehdr_start],
1691 libc_cv_ehdr_start, [
1692 old_CFLAGS="$CFLAGS"
1693 old_LDFLAGS="$LDFLAGS"
1695 CFLAGS="$CFLAGS -fPIC"
1696 LDFLAGS="$LDFLAGS -nostdlib -nostartfiles -shared $no_ssp"
1698 AC_LINK_IFELSE([AC_LANG_SOURCE([
1703 extern const Ehdr __ehdr_start __attribute__ ((visibility ("hidden")));
1704 long ehdr (void) { return __ehdr_start.val; }
1706 [if $READELF -r conftest | grep -F __ehdr_start >/dev/null; then
1707 libc_cv_ehdr_start=broken
1709 libc_cv_ehdr_start=yes
1710 fi], [libc_cv_ehdr_start=no])
1711 CFLAGS="$old_CFLAGS"
1712 LDFLAGS="$old_LDFLAGS"
1715 if test "$libc_cv_ehdr_start" = yes; then
1716 AC_DEFINE([HAVE_EHDR_START])
1717 elif test "$libc_cv_ehdr_start" = broken; then
1718 AC_MSG_WARN([linker is broken -- you should upgrade])
1721 AC_CACHE_CHECK(for __builtin_trap with no external dependencies,
1722 libc_cv_builtin_trap, [dnl
1723 libc_cv_builtin_trap=no
1724 AC_TRY_COMPILE([], [__builtin_trap ()], [
1725 libc_undefs=`$NM -u conftest.o |
1726 LC_ALL=C $AWK '$1 == "U" { print $2 | "sort -u"; next } { exit(1) }' \
1727 2>&AS_MESSAGE_LOG_FD` || {
1728 AC_MSG_ERROR([confusing output from $NM -u])
1730 echo >&AS_MESSAGE_LOG_FD "libc_undefs='$libc_undefs'"
1731 if test -z "$libc_undefs"; then
1732 libc_cv_builtin_trap=yes
1734 if test $libc_cv_builtin_trap = yes; then
1735 AC_DEFINE([HAVE_BUILTIN_TRAP])
1738 dnl C++ feature tests.
1741 AC_CACHE_CHECK([whether the C++ compiler supports thread_local],
1742 libc_cv_cxx_thread_local, [
1743 old_CXXFLAGS="$CXXFLAGS"
1744 CXXFLAGS="$CXXFLAGS -std=gnu++11"
1745 AC_COMPILE_IFELSE([AC_LANG_SOURCE([
1748 // Compiler support.
1755 S * get () { return &s; }
1757 // libstdc++ support.
1758 #ifndef _GLIBCXX_HAVE___CXA_THREAD_ATEXIT_IMPL
1759 #error __cxa_thread_atexit_impl not supported
1762 [libc_cv_cxx_thread_local=yes],
1763 [libc_cv_cxx_thread_local=no])
1764 CXXFLAGS="$old_CXXFLAGS"
1766 AC_SUBST(libc_cv_cxx_thread_local)
1769 dnl End of C++ feature tests.
1771 ### End of automated tests.
1772 ### Now run sysdeps configure fragments.
1774 # They also can set these variables.
1776 ldd_rewrite_script=no
1777 libc_cv_sysconfdir=$sysconfdir
1778 libc_cv_localstatedir=$localstatedir
1779 libc_cv_gcc_unwind_find_fde=no
1782 # Iterate over all the sysdep directories we will use, running their
1783 # configure fragments.
1784 for dir in $sysnames; do
1787 *) dest=$srcdir/$dir ;;
1789 if test -r $dest/configure; then
1790 AC_MSG_RESULT(running configure fragment for $dir)
1795 if test x"$build_mathvec" = xnotset; then
1798 LIBC_CONFIG_VAR([build-mathvec], [$build_mathvec])
1800 AC_SUBST(libc_extra_cflags)
1801 AC_SUBST(libc_extra_cppflags)
1803 if test x$libc_cv_gcc_unwind_find_fde = xyes; then
1804 AC_DEFINE(EXPORT_UNWIND_FIND_FDE)
1806 AC_SUBST(libc_cv_gcc_unwind_find_fde)
1808 # A sysdeps configure fragment can reset this if IFUNC is not actually
1809 # usable even though the assembler knows how to generate the symbol type.
1810 if test x"$libc_cv_ld_gnu_indirect_function" = xyes; then
1811 AC_DEFINE(HAVE_IFUNC)
1814 if test x"$libc_cv_gcc_indirect_function" = xyes; then
1815 AC_DEFINE(HAVE_GCC_IFUNC)
1818 # This is far from the AC_ARG_ENABLE that sets it so that a sysdeps
1819 # configure fragment can override the value to prevent this AC_DEFINE.
1821 if test "x$use_nscd" != xno; then
1822 AC_DEFINE([USE_NSCD])
1824 if test "x$build_nscd" = xdefault; then
1825 build_nscd=$use_nscd
1828 AC_SUBST(libc_cv_slibdir)
1829 AC_SUBST(libc_cv_rtlddir)
1830 AC_SUBST(libc_cv_complocaledir)
1831 AC_SUBST(libc_cv_sysconfdir)
1832 AC_SUBST(libc_cv_localstatedir)
1833 AC_SUBST(libc_cv_rootsbindir)
1835 if test x$use_ldconfig = xyes; then
1836 AC_DEFINE(USE_LDCONFIG)
1838 AC_SUBST(use_ldconfig)
1839 AC_SUBST(ldd_rewrite_script)
1844 AC_CACHE_CHECK([whether -fPIC is default], libc_cv_pic_default,
1845 [libc_cv_pic_default=yes
1846 cat > conftest.c <<EOF
1847 #if defined __PIC__ || defined __pic__ || defined PIC || defined pic
1848 # error PIC is default.
1851 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1852 libc_cv_pic_default=no
1855 AC_SUBST(libc_cv_pic_default)
1857 AC_CACHE_CHECK([whether -fPIE is default], libc_cv_cc_pie_default,
1858 [libc_cv_cc_pie_default=yes
1859 cat > conftest.c <<EOF
1860 #if defined __PIE__ || defined __pie__ || defined PIE || defined pie
1861 # error PIE is default.
1864 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1865 libc_cv_cc_pie_default=no
1868 libc_cv_pie_default=$libc_cv_cc_pie_default
1869 AC_SUBST(libc_cv_cc_pie_default)
1870 AC_SUBST(libc_cv_pie_default)
1872 # Set the `multidir' variable by grabbing the variable from the compiler.
1873 # We do it once and save the result in a generated makefile.
1874 libc_cv_multidir=`${CC-cc} $CFLAGS $CPPFLAGS -print-multi-directory`
1875 AC_SUBST(libc_cv_multidir)
1877 if test "$static_pie" = yes; then
1878 # The linker must support --no-dynamic-linker.
1879 if test "$libc_cv_no_dynamic_linker" != yes; then
1880 AC_MSG_ERROR([linker support for --no-dynamic-linker needed])
1883 libc_cv_pie_default=yes
1884 AC_DEFINE(ENABLE_STATIC_PIE)
1886 LIBC_CONFIG_VAR([enable-static-pie], [$static_pie])
1889 AC_SUBST(static_nss)
1893 dnl See sysdeps/mach/configure.ac for this variable.
1894 AC_SUBST(mach_interface_list)
1896 VERSION=`sed -n -e 's/^#define VERSION "\([^"]*\)"/\1/p' < $srcdir/version.h`
1897 RELEASE=`sed -n -e 's/^#define RELEASE "\([^"]*\)"/\1/p' < $srcdir/version.h`
1901 AC_CONFIG_FILES([config.make Makefile])
1902 AC_CONFIG_COMMANDS([default],[[
1903 case $CONFIG_FILES in *config.make*)
1904 echo "$config_vars" >> config.make;;
1906 test -d bits || mkdir bits]],[[config_vars='$config_vars']])