configure.ac

   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])
   7
   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])
  14
  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 */'])])
  19
  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 "$CPP"; then
  29   CPP=
  30 fi
  31 if test -z "$CPP"; then
  32   CPP="$CC -E"
  33 fi
  34 AC_SUBST(CPP)dnl
  35 ])# AC_PROG_CPP
  36
  37 # We require GCC.  Override _AC_PROG_CC_C89 here to work around the Autoconf
  38 # issue discussed in
  39 # <https://sourceware.org/ml/libc-alpha/2013-01/msg00757.html>.
  40 AC_DEFUN([_AC_PROG_CC_C89], [[$1]])
  41
  42 dnl This is here so we can set $subdirs directly based on configure fragments.
  43 AC_CONFIG_SUBDIRS()
  44
  45 AC_CANONICAL_HOST
  46
  47 AC_PROG_CC
  48 if test $host != $build; then
  49   AC_CHECK_PROGS(BUILD_CC, gcc cc)
  50 fi
  51 AC_SUBST(cross_compiling)
  52 AC_PROG_CPP
  53 AC_CHECK_TOOL(READELF, readelf, false)
  54
  55 # We need the C++ compiler only for testing.
  56 AC_PROG_CXX
  57 # It's useless to us if it can't link programs (e.g. missing -lstdc++).
  58 AC_CACHE_CHECK([whether $CXX can link programs], libc_cv_cxx_link_ok, [dnl
  59 AC_LANG_PUSH([C++])
  60 # Default, dynamic case.
  61 AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
  62                [libc_cv_cxx_link_ok=yes],
  63                [libc_cv_cxx_link_ok=no])
  64 # Static case.
  65 old_LDFLAGS="$LDFLAGS"
  66 LDFLAGS="$LDFLAGS -static"
  67 AC_LINK_IFELSE([AC_LANG_SOURCE([
  68 #include <iostream>
  69
  70 int
  71 main()
  72 {
  73   std::cout << "Hello, world!";
  74   return 0;
  75 }
  76 ])],
  77                [],
  78                [libc_cv_cxx_link_ok=no])
  79 LDFLAGS="$old_LDFLAGS"
  80 AC_LANG_POP([C++])])
  81 AS_IF([test $libc_cv_cxx_link_ok != yes], [CXX=])
  82
  83 if test "`cd $srcdir; pwd -P`" = "`pwd -P`"; then
  84   AC_MSG_ERROR([you must configure in a separate build directory])
  85 fi
  86
  87 # This will get text that should go into config.make.
  88 config_vars=
  89
  90 # Check for a --with-gd argument and set libgd-LDFLAGS in config.make.
  91 AC_ARG_WITH([gd],
  92             AC_HELP_STRING([--with-gd=DIR],
  93                            [find libgd include dir and library with prefix DIR]),
  94             [dnl
  95 case "$with_gd" in
  96 yes|''|no) ;;
  97 *) libgd_include="-I$withval/include"
  98    libgd_ldflags="-L$withval/lib" ;;
  99 esac
 100 ])
 101 AC_ARG_WITH([gd-include],
 102             AC_HELP_STRING([--with-gd-include=DIR],
 103                            [find libgd include files in DIR]),
 104             [dnl
 105 case "$with_gd_include" in
 106 ''|no) ;;
 107 *) libgd_include="-I$withval" ;;
 108 esac
 109 ])
 110 AC_ARG_WITH([gd-lib],
 111             AC_HELP_STRING([--with-gd-lib=DIR],
 112                            [find libgd library files in DIR]),
 113             [dnl
 114 case "$with_gd_lib" in
 115 ''|no) ;;
 116 *) libgd_ldflags="-L$withval" ;;
 117 esac
 118 ])
 119
 120 if test -n "$libgd_include"; then
 121   config_vars="$config_vars
 122 CFLAGS-memusagestat.c = $libgd_include"
 123 fi
 124 if test -n "$libgd_ldflags"; then
 125   config_vars="$config_vars
 126 libgd-LDFLAGS = $libgd_ldflags"
 127 fi
 128
 129 dnl Arguments to specify presence of other packages/features.
 130 AC_ARG_WITH([binutils],
 131             AC_HELP_STRING([--with-binutils=PATH],
 132                            [specify location of binutils (as and ld)]),
 133             [path_binutils=$withval],
 134             [path_binutils=''])
 135 AC_ARG_WITH([selinux],
 136             AC_HELP_STRING([--with-selinux],
 137                            [if building with SELinux support]),
 138             [with_selinux=$withval],
 139             [with_selinux=auto])
 140
 141 AC_ARG_WITH([headers],
 142             AC_HELP_STRING([--with-headers=PATH],
 143                            [location of system headers to use
 144                             (for example /usr/src/linux/include)
 145                             @<:@default=compiler default@:>@]),
 146             [sysheaders=$withval],
 147             [sysheaders=''])
 148 AC_SUBST(sysheaders)
 149
 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=$withval],
 155             [use_default_link=default])
 156
 157 dnl Additional build flags injection.
 158 AC_ARG_WITH([nonshared-cflags],
 159             AC_HELP_STRING([--with-nonshared-cflags=CFLAGS],
 160                            [build nonshared libraries with additional CFLAGS]),
 161             [extra_nonshared_cflags=$withval],
 162             [extra_nonshared_cflags=])
 163 AC_SUBST(extra_nonshared_cflags)
 164
 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=$enableval],
 169               [enable_sanity=yes])
 170
 171 AC_ARG_ENABLE([shared],
 172               AC_HELP_STRING([--enable-shared],
 173                              [build shared library @<:@default=yes if GNU ld@:>@]),
 174               [shared=$enableval],
 175               [shared=yes])
 176 AC_ARG_ENABLE([profile],
 177               AC_HELP_STRING([--enable-profile],
 178                              [build profiled library @<:@default=no@:>@]),
 179               [profile=$enableval],
 180               [profile=no])
 181 AC_ARG_ENABLE([static-pie],
 182               AC_HELP_STRING([--enable-static-pie],
 183                              [enable static PIE support and use it in the testsuite @<:@default=no@:>@]),
 184               [static_pie=$enableval],
 185               [static_pie=no])
 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=$enableval],
 190               [enable_timezone_tools=yes])
 191 AC_SUBST(enable_timezone_tools)
 192
 193 AC_ARG_ENABLE([hardcoded-path-in-tests],
 194               AC_HELP_STRING([--enable-hardcoded-path-in-tests],
 195                              [hardcode newly built glibc path in tests @<:@default=no@:>@]),
 196               [hardcoded_path_in_tests=$enableval],
 197               [hardcoded_path_in_tests=no])
 198 AC_SUBST(hardcoded_path_in_tests)
 199
 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)
 207 fi
 208
 209 AC_ARG_ENABLE([hidden-plt],
 210               AC_HELP_STRING([--disable-hidden-plt],
 211                              [do not hide internal function calls to avoid PLT]),
 212               [hidden=$enableval],
 213               [hidden=yes])
 214 if test "x$hidden" = xno; then
 215   AC_DEFINE(NO_HIDDEN)
 216 fi
 217
 218 AC_ARG_ENABLE([bind-now],
 219               AC_HELP_STRING([--enable-bind-now],
 220                              [disable lazy relocations in DSOs]),
 221               [bindnow=$enableval],
 222               [bindnow=no])
 223 AC_SUBST(bindnow)
 224 if test "x$bindnow" = xyes; then
 225   AC_DEFINE(BIND_NOW)
 226 fi
 227
 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: \"$enable_stack_protector\"]);;
 238 esac
 239
 240 dnl On some platforms we cannot use dynamic loading.  We must provide
 241 dnl static NSS modules.
 242 AC_ARG_ENABLE([static-nss],
 243               AC_HELP_STRING([--enable-static-nss],
 244                              [build static NSS modules @<:@default=no@:>@]),
 245               [static_nss=$enableval],
 246               [static_nss=no])
 247 dnl Enable static NSS also if we build no shared objects.
 248 if test x"$static_nss" = xyes || test x"$shared" = xno; then
 249   static_nss=yes
 250   AC_DEFINE(DO_STATIC_NSS)
 251 fi
 252
 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=$enableval],
 257               [force_install=yes])
 258 AC_SUBST(force_install)
 259
 260 AC_ARG_ENABLE([maintainer-mode],
 261               AC_HELP_STRING([--enable-maintainer-mode],
 262                              [enable make rules and dependencies not useful (and sometimes confusing) to the casual installer]),
 263               [maintainer=$enableval],
 264               [maintainer=no])
 265
 266 dnl On some platforms we allow dropping compatibility with all kernel
 267 dnl versions.
 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=$enableval],
 272               [])
 273 dnl Prevent unreasonable values.
 274 if test "$minimum_kernel" = yes || test "$minimum_kernel" = no; then
 275   # Better nothing than this.
 276   minimum_kernel=""
 277 else
 278   if test "$minimum_kernel" = current; then
 279     minimum_kernel=`uname -r 2>/dev/null` || minimum_kernel=
 280   fi
 281 fi
 282
 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
 285 dnl appropriate.
 286 AC_ARG_ENABLE([all-warnings],
 287               AC_HELP_STRING([--enable-all-warnings],
 288                              [enable all useful warnings gcc can issue]),
 289               [all_warnings=$enableval],
 290               [])
 291 AC_SUBST(all_warnings)
 292
 293 AC_ARG_ENABLE([werror],
 294               AC_HELP_STRING([--disable-werror],
 295                              [do not build with -Werror]),
 296               [enable_werror=$enableval],
 297               [enable_werror=yes])
 298 AC_SUBST(enable_werror)
 299
 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=$enableval],
 304               [multi_arch=default])
 305
 306 AC_ARG_ENABLE([experimental-malloc],
 307               AC_HELP_STRING([--disable-experimental-malloc],
 308                              [disable experimental malloc features]),
 309               [experimental_malloc=$enableval],
 310               [experimental_malloc=yes])
 311 AC_SUBST(experimental_malloc)
 312
 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=$enableval],
 317               [build_crypt=yes])
 318 AC_SUBST(build_crypt)
 319
 320 AC_ARG_ENABLE([nss-crypt],
 321               AC_HELP_STRING([--enable-nss-crypt],
 322                              [enable libcrypt to use nss]),
 323               [nss_crypt=$enableval],
 324               [nss_crypt=no])
 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])
 327   nss_crypt=no
 328 fi
 329 if test x$nss_crypt = xyes; then
 330   nss_includes=-I$(nss-config --includedir 2>/dev/null)
 331   if test $? -ne 0; then
 332     AC_MSG_ERROR([cannot find include directory with nss-config])
 333   fi
 334   nspr_includes=-I$(nspr-config --includedir 2>/dev/null)
 335   if test $? -ne 0; then
 336     AC_MSG_ERROR([cannot find include directory with nspr-config])
 337   fi
 338   old_CFLAGS="$CFLAGS"
 339   CFLAGS="$CFLAGS $nss_includes $nspr_includes"
 340   AC_COMPILE_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
 341 #include <hasht.h>
 342 #include <nsslowhash.h>
 343 void f (void) { NSSLOW_Init (); }])],
 344              libc_cv_nss_crypt=yes,
 345              AC_MSG_ERROR([
 346 cannot find NSS headers with lowlevel hash function interfaces]))
 347   old_LIBS="$LIBS"
 348   old_LDFLAGS="$LDFLAGS"
 349   LIBS="$LIBS -lfreebl3"
 350   AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
 351 #include <hasht.h>
 352 #include <nsslowhash.h>],
 353                                   [NSSLOW_Init();])],
 354                  libc_cv_nss_crypt=yes,
 355                  AC_MSG_ERROR([
 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="$LDFLAGS -static"
 361   AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
 362 #include <hasht.h>
 363 #include <nsslowhash.h>],
 364                                   [NSSLOW_Init();])],
 365                  libc_cv_static_nss_crypt=yes,
 366                  libc_cv_static_nss_crypt=no)
 367   LDFLAGS="$old_LDFLAGS"
 368   CFLAGS="$old_CFLAGS"
 369   LIBS="$old_LIBS"
 370 else
 371   libc_cv_nss_crypt=no
 372   libc_cv_static_nss_crypt=no
 373 fi
 374 AC_SUBST(libc_cv_nss_crypt)
 375 AC_SUBST(libc_cv_static_nss_crypt)
 376
 377
 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=$enableval],
 382               [link_obsolete_rpc=no])
 383 AC_SUBST(link_obsolete_rpc)
 384
 385 if test "$link_obsolete_rpc" = yes; then
 386   AC_DEFINE(LINK_OBSOLETE_RPC)
 387 fi
 388
 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=$enableval],
 393               [build_obsolete_nsl=no])
 394 AC_SUBST(build_obsolete_nsl)
 395
 396 if test "$build_obsolete_nsl" = yes; then
 397   AC_DEFINE(LINK_OBSOLETE_NSL)
 398 fi
 399
 400 AC_ARG_ENABLE([systemtap],
 401               [AS_HELP_STRING([--enable-systemtap],
 402                [enable systemtap static probe points @<:@default=no@:>@])],
 403               [systemtap=$enableval],
 404               [systemtap=no])
 405 if test "x$systemtap" != xno; then
 406   AC_CACHE_CHECK([for systemtap static probe support], libc_cv_sdt, [dnl
 407   old_CFLAGS="$CFLAGS"
 408   CFLAGS="-std=gnu11 $CFLAGS"
 409   AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <sys/sdt.h>
 410 void foo (int i, void *p)
 411 {
 412   asm ("" STAP_PROBE_ASM (foo, bar, STAP_PROBE_ASM_TEMPLATE (2)) ""
 413        :: STAP_PROBE_ASM_OPERANDS (2, i, p));
 414 }]])], [libc_cv_sdt=yes], [libc_cv_sdt=no])
 415   CFLAGS="$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])
 420   fi
 421 fi
 422
 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])
 428 AC_SUBST(build_nscd)
 429
 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],
 435               [use_nscd=yes])
 436
 437 AC_ARG_ENABLE([pt_chown],
 438               [AS_HELP_STRING([--enable-pt_chown],
 439                [Enable building and installing pt_chown])],
 440               [build_pt_chown=$enableval],
 441               [build_pt_chown=no])
 442 AC_SUBST(build_pt_chown)
 443 if test "$build_pt_chown" = yes; then
 444   AC_DEFINE(HAVE_PT_CHOWN)
 445 fi
 446
 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=$enableval],
 451               [have_tunables=yes])
 452 AC_SUBST(have_tunables)
 453 if test "$have_tunables" = yes; then
 454   AC_DEFINE(HAVE_TUNABLES)
 455 fi
 456
 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 # $host_os of `gnu*' here to be `gnu-gnu*' just so that it can tell.
 460 # This doesn't get used much beyond that, so it's fairly safe.
 461 case "$host_os" in
 462 linux*)
 463   ;;
 464 gnu*)
 465   host_os=`echo $host_os | sed -e 's/gnu/gnu-gnu/'`
 466   ;;
 467 esac
 468
 469 AC_ARG_ENABLE([mathvec],
 470               [AS_HELP_STRING([--enable-mathvec],
 471               [Enable building and installing mathvec @<:@default depends on architecture@:>@])],
 472               [build_mathvec=$enableval],
 473               [build_mathvec=notset])
 474
 475 AC_TRY_COMPILE([], [
 476 #ifndef __CET__
 477 # error no CET compiler support
 478 #endif],
 479                [libc_cv_compiler_default_cet=yes],
 480                [libc_cv_compiler_default_cet=no])
 481
 482 AC_ARG_ENABLE([cet],
 483               AC_HELP_STRING([--enable-cet],
 484                              [enable Intel Control-flow Enforcement Technology (CET), x86 only]),
 485               [enable_cet=$enableval],
 486               [enable_cet=$libc_cv_compiler_default_cet])
 487
 488 # We keep the original values in `$config_*' and never modify them, so we
 489 # can write them unchanged into config.make.  Everything else uses
 490 # $machine, $vendor, and $os, and changes them whenever convenient.
 491 config_machine=$host_cpu config_vendor=$host_vendor config_os=$host_os
 492
 493 # Don't allow vendor == "unknown"
 494 test "$config_vendor" = unknown && config_vendor=
 495 config_os="`echo $config_os | sed 's/^unknown-//'`"
 496
 497 # Some configurations imply other options.
 498 elf=yes
 499
 500 # The configure fragment of a port can modify these to supplement
 501 # or override the table in the case statement below.  No fragment should
 502 # ever change the config_* variables, however.
 503 machine=$config_machine
 504 vendor=$config_vendor
 505 os=$config_os
 506 base_os=''
 507
 508 submachine=
 509 AC_ARG_WITH([cpu],
 510             AS_HELP_STRING([--with-cpu=CPU], [select code for CPU variant]),
 511             [dnl
 512   case "$withval" in
 513   yes|'') AC_MSG_ERROR([--with-cpu requires an argument]) ;;
 514   no) ;;
 515   *) submachine="$withval" ;;
 516   esac
 517 ])
 518
 519 # An preconfigure script can set this when it wants to disable the sanity
 520 # check below.
 521 libc_config_ok=no
 522
 523 # A preconfigure script for a system that may or may not use fpu
 524 # sysdeps directories sets this to a preprocessor conditional for
 525 # whether to use such directories.
 526 with_fp_cond=1
 527
 528 dnl Let sysdeps/*/preconfigure act here.
 529 LIBC_PRECONFIGURE([$srcdir], [for sysdeps])
 530
 531
 532 ###
 533 ### By using the undocumented --enable-hacker-mode option for configure
 534 ### one can skip this test to make the configuration not fail for unsupported
 535 ### platforms.
 536 ###
 537 if test -z "$enable_hacker_mode" && test x"$libc_config_ok" != xyes; then
 538   case "$machine-$host_os" in
 539   *-linux* | *-gnu*)
 540     ;;
 541   *)
 542     AC_MSG_ERROR([
 543 *** The GNU C library is currently unavailable for this platform.
 544 *** If you are interested in seeing glibc on this platform visit
 545 *** the "How to submit a new port" in the wiki:
 546 ***   https://sourceware.org/glibc/wiki/#Development
 547 *** and join the community!])
 548     ;;
 549   esac
 550 fi
 551
 552 # Set base_machine if not set by a preconfigure fragment.
 553 test -n "$base_machine" || base_machine=$machine
 554 AC_SUBST(base_machine)
 555
 556 # Determine whether to use fpu or nofpu sysdeps directories.
 557 AC_CACHE_CHECK([for use of fpu sysdeps directories],
 558                libc_cv_with_fp, [dnl
 559 cat > conftest.c <<EOF
 560 #if $with_fp_cond
 561 int dummy;
 562 #else
 563 # error "no hardware floating point"
 564 #endif
 565 EOF
 566 libc_cv_with_fp=no
 567 if ${CC-cc} $CFLAGS $CPPFLAGS -S conftest.c -o conftest.s \
 568    1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
 569   libc_cv_with_fp=yes
 570 fi
 571 rm -f conftest*])
 572 AC_SUBST(libc_cv_with_fp)
 573
 574 AC_CACHE_CHECK(for -fstack-protector, libc_cv_ssp, [dnl
 575 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector],
 576                    [libc_cv_ssp=yes],
 577                    [libc_cv_ssp=no])
 578 ])
 579
 580 AC_CACHE_CHECK(for -fstack-protector-strong, libc_cv_ssp_strong, [dnl
 581 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-strong],
 582                    [libc_cv_ssp_strong=yes],
 583                    [libc_cv_ssp_strong=no])
 584 ])
 585
 586 AC_CACHE_CHECK(for -fstack-protector-all, libc_cv_ssp_all, [dnl
 587 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-all],
 588                    [libc_cv_ssp_all=yes],
 589                    [libc_cv_ssp_all=no])
 590 ])
 591
 592 stack_protector=
 593 no_stack_protector=
 594 if test "$libc_cv_ssp" = yes; then
 595   no_stack_protector="-fno-stack-protector -DSTACK_PROTECTOR_LEVEL=0"
 596   AC_DEFINE(HAVE_CC_NO_STACK_PROTECTOR)
 597 fi
 598
 599 if test "$enable_stack_protector" = yes && test "$libc_cv_ssp" = yes; then
 600   stack_protector="-fstack-protector"
 601   AC_DEFINE(STACK_PROTECTOR_LEVEL, 1)
 602 elif test "$enable_stack_protector" = all && test "$libc_cv_ssp_all" = yes; then
 603   stack_protector="-fstack-protector-all"
 604   AC_DEFINE(STACK_PROTECTOR_LEVEL, 2)
 605 elif test "$enable_stack_protector" = strong && test "$libc_cv_ssp_strong" = yes; then
 606   stack_protector="-fstack-protector-strong"
 607   AC_DEFINE(STACK_PROTECTOR_LEVEL, 3)
 608 else
 609   stack_protector="-fno-stack-protector"
 610   AC_DEFINE(STACK_PROTECTOR_LEVEL, 0)
 611 fi
 612 AC_SUBST(libc_cv_ssp)
 613 AC_SUBST(stack_protector)
 614 AC_SUBST(no_stack_protector)
 615
 616 if test -n "$stack_protector"; then
 617   dnl Don't run configure tests with stack-protection on, to avoid problems with
 618   dnl bootstrapping.
 619   no_ssp=-fno-stack-protector
 620 else
 621   no_ssp=
 622
 623   if test "$enable_stack_protector" != no; then
 624     AC_MSG_ERROR([--enable-stack-protector=$enable_stack_protector specified, but specified level of stack protection is not supported by the compiler.])
 625   fi
 626 fi
 627
 628 # For the multi-arch option we need support in the assembler & linker.
 629 AC_CACHE_CHECK([for assembler and linker STT_GNU_IFUNC support],
 630                libc_cv_ld_gnu_indirect_function, [dnl
 631 cat > conftest.S <<EOF
 632 .type foo,%gnu_indirect_function
 633 foo:
 634 .globl _start
 635 _start:
 636 .globl __start
 637 __start:
 638 .data
 639 #ifdef _LP64
 640 .quad foo
 641 #else
 642 .long foo
 643 #endif
 644 EOF
 645 libc_cv_ld_gnu_indirect_function=no
 646 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
 647             -nostartfiles -nostdlib $no_ssp \
 648             -o conftest conftest.S 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
 649   # Do a link to see if the backend supports IFUNC relocs.
 650   $READELF -r conftest 1>&AS_MESSAGE_LOG_FD
 651   LC_ALL=C $READELF -r conftest | grep 'no relocations' >/dev/null || {
 652     libc_cv_ld_gnu_indirect_function=yes
 653   }
 654 fi
 655 rm -f conftest*])
 656
 657 # Check if gcc supports attribute ifunc as it is used in libc_ifunc macro.
 658 AC_CACHE_CHECK([for gcc attribute ifunc support],
 659                libc_cv_gcc_indirect_function, [dnl
 660 cat > conftest.c <<EOF
 661 extern int func (int);
 662 int used_func (int a)
 663 {
 664   return a;
 665 }
 666 static void *resolver ()
 667 {
 668   return &used_func;
 669 }
 670 extern __typeof (func) func __attribute__ ((ifunc ("resolver")));
 671 EOF
 672 libc_cv_gcc_indirect_function=no
 673 if ${CC-cc} -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD \
 674    2>&AS_MESSAGE_LOG_FD ; then
 675   if $READELF -s conftest.o | grep IFUNC >/dev/null 2>&AS_MESSAGE_LOG_FD; then
 676     libc_cv_gcc_indirect_function=yes
 677   fi
 678 fi
 679 rm -f conftest*])
 680
 681 # Check if linker supports textrel relocation with ifunc (used on elf/tests).
 682 # Note that it relies on libc_cv_ld_gnu_indirect_function test above.
 683 AC_CACHE_CHECK([whether the linker supports textrels along with ifunc],
 684                libc_cv_textrel_ifunc, [dnl
 685 cat > conftest.S <<EOF
 686 .type foo,%gnu_indirect_function
 687 foo:
 688 .globl _start
 689 _start:
 690 .globl __start
 691 __start:
 692 .data
 693 #ifdef _LP64
 694 .quad foo
 695 #else
 696 .long foo
 697 #endif
 698 .text
 699 .globl address
 700 address:
 701 #ifdef _LP64
 702 .quad address
 703 #else
 704 .long address
 705 #endif
 706 EOF
 707 libc_cv_textrel_ifunc=no
 708 if test $libc_cv_ld_gnu_indirect_function = yes; then
 709    if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp -pie -o conftest conftest.S); then
 710      libc_cv_textrel_ifunc=yes
 711    fi
 712 fi
 713 rm -f conftest*])
 714 AC_SUBST(libc_cv_textrel_ifunc)
 715
 716 # Check if gcc warns about alias for function with incompatible types.
 717 AC_CACHE_CHECK([if compiler warns about alias for function with incompatible types],
 718                libc_cv_gcc_incompatible_alias, [dnl
 719 cat > conftest.c <<EOF
 720 int __redirect_foo (const void *s, int c);
 721
 722 __typeof (__redirect_foo) *foo_impl (void) __asm__ ("foo");
 723 __typeof (__redirect_foo) *foo_impl (void)
 724 {
 725   return 0;
 726 }
 727
 728 extern __typeof (__redirect_foo) foo_alias __attribute__ ((alias ("foo")));
 729 EOF
 730 libc_cv_gcc_incompatible_alias=yes
 731 if ${CC-cc} -Werror -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
 732   libc_cv_gcc_incompatible_alias=no
 733 fi
 734 rm -f conftest*])
 735
 736 if test x"$libc_cv_ld_gnu_indirect_function" != xyes; then
 737   if test x"$multi_arch" = xyes; then
 738     AC_MSG_ERROR([--enable-multi-arch support requires assembler and linker support])
 739   else
 740     multi_arch=no
 741   fi
 742 fi
 743 if test x"$libc_cv_gcc_indirect_function" != xyes; then
 744   # GCC 8+ emits a warning for alias with incompatible types and it might
 745   # fail to build ifunc resolvers aliases to either weak or internal
 746   # symbols.  Disables multiarch build in this case.
 747   if test x"$libc_cv_gcc_incompatible_alias" == xyes; then
 748     AC_MSG_WARN([gcc emits a warning for alias between functions of incompatible types])
 749     if test x"$multi_arch" = xyes; then
 750       AC_MSG_ERROR([--enable-multi-arch support requires a gcc with gnu-indirect-function support])
 751     fi
 752     AC_MSG_WARN([Multi-arch is disabled.])
 753     multi_arch=no
 754   elif test x"$multi_arch" = xyes; then
 755     AC_MSG_WARN([--enable-multi-arch support recommends a gcc with gnu-indirect-function support.
 756 Please use a gcc which supports it by default or configure gcc with --enable-gnu-indirect-function])
 757   fi
 758 fi
 759 multi_arch_d=
 760 if test x"$multi_arch" != xno; then
 761   multi_arch_d=/multiarch
 762 fi
 763
 764 # Compute the list of sysdep directories for this configuration.
 765 # This can take a while to compute.
 766 sysdep_dir=$srcdir/sysdeps
 767 AC_MSG_CHECKING(sysdep dirs)
 768 dnl We need to use [ and ] for other purposes for a while now.
 769 changequote(,)dnl
 770 # Make sco3.2v4 become sco3.2.4 and sunos4.1.1_U1 become sunos4.1.1.U1.
 771 os="`echo $os | sed 's/\([0-9A-Z]\)[v_]\([0-9A-Z]\)/\1.\2/g'`"
 772
 773 test "x$base_os" != x || case "$os" in
 774 gnu*)
 775   base_os=mach/hurd ;;
 776 linux*)
 777   base_os=unix/sysv ;;
 778 esac
 779
 780 # For sunos4.1.1, try sunos4.1.1, then sunos4.1, then sunos4, then sunos.
 781 tail=$os
 782 ostry=$os
 783 while o=`echo $tail | sed 's/\.[^.]*$//'`; test $o != $tail; do
 784   ostry="$ostry /$o"
 785   tail=$o
 786 done
 787 o=`echo $tail | sed 's/[0-9]*$//'`
 788 if test $o != $tail; then
 789   ostry="$ostry /$o"
 790 fi
 791 # For linux-gnu, try linux-gnu, then linux.
 792 o=`echo $tail | sed 's/-.*$//'`
 793 if test $o != $tail; then
 794   ostry="$ostry /$o"
 795 fi
 796
 797 # For unix/sysv/sysv4, try unix/sysv/sysv4, then unix/sysv, then unix.
 798 base=
 799 tail=$base_os
 800 while b=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$b"; do
 801   set $b
 802   base="$base /$1"
 803   tail="$2"
 804 done
 805
 806 # For sparc/sparc32, try sparc/sparc32 and then sparc.
 807 mach=
 808 tail=$machine${submachine:+/$submachine}
 809 while m=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$m"; do
 810   set $m
 811   # Prepend the machine's FPU directory unless --without-fp.
 812   if test "$libc_cv_with_fp" = yes; then
 813     maybe_fpu=/fpu
 814   else
 815     maybe_fpu=/nofpu
 816   fi
 817   # For each machine term, try it with and then without /multiarch.
 818   for try_fpu in $maybe_fpu ''; do
 819     for try_multi in $multi_arch_d ''; do
 820       mach="$mach /$1$try_fpu$try_multi"
 821     done
 822   done
 823   tail="$2"
 824 done
 825
 826 dnl We are done with glob and regexp uses of [ and ]; return to autoconf.
 827 changequote([,])dnl
 828
 829 # Find what sysdep directories exist.
 830 sysnames=
 831 for b in $base ''; do
 832   for m0 in $mach ''; do
 833     for v in /$vendor ''; do
 834       test "$v" = / && continue
 835       for o in /$ostry ''; do
 836         test "$o" = / && continue
 837         for m in $mach ''; do
 838           try_suffix="$m0$b$v$o$m"
 839           if test -n "$try_suffix"; then
 840             try_srcdir="${srcdir}/"
 841             try="sysdeps$try_suffix"
 842             test -n "$enable_debug_configure" &&
 843             echo "$0 [DEBUG]: try $try" >&2
 844             if test -d "$try_srcdir$try"; then
 845               sysnames="$sysnames $try"
 846               { test -n "$o" || test -n "$b"; } && os_used=t
 847               { test -n "$m" || test -n "$m0"; } && machine_used=t
 848               case x${m0:-$m} in
 849               x*/$submachine) submachine_used=t ;;
 850               esac
 851             fi
 852           fi
 853         done
 854       done
 855     done
 856   done
 857 done
 858
 859 # If the assembler supports gnu_indirect_function symbol type and the
 860 # architecture supports multi-arch, we enable multi-arch by default.
 861 case $sysnames in
 862 *"$multi_arch_d"*)
 863   ;;
 864 *)
 865   test x"$multi_arch" = xdefault && multi_arch=no
 866   ;;
 867 esac
 868 if test x"$multi_arch" != xno; then
 869   AC_DEFINE(USE_MULTIARCH)
 870 fi
 871 AC_SUBST(multi_arch)
 872
 873 if test -z "$os_used" && test "$os" != none; then
 874   AC_MSG_ERROR(Operating system $os is not supported.)
 875 fi
 876 if test -z "$machine_used" && test "$machine" != none; then
 877   AC_MSG_ERROR(The $machine is not supported.)
 878 fi
 879 if test -z "$submachine_used" && test -n "$submachine"; then
 880   AC_MSG_ERROR(The $submachine subspecies of $host_cpu is not supported.)
 881 fi
 882 AC_SUBST(submachine)
 883
 884 # We have now validated the configuration.
 885
 886 # Expand the list of system names into a full list of directories
 887 # from each element's parent name and Implies file (if present).
 888 set $sysnames
 889 names=
 890 while test $# -gt 0; do
 891   name=$1
 892   shift
 893
 894   case " $names " in *" $name "*)
 895     # Already in the list.
 896     continue
 897   esac
 898
 899   # Report each name as we discover it, so there is no long pause in output.
 900   echo $ECHO_N "$name $ECHO_C" >&AS_MESSAGE_FD
 901
 902   name_base=`echo $name | sed -e 's@\(.*sysdeps\)/.*@\1@'`
 903
 904   case $name in
 905     /*) xsrcdir= ;;
 906     *)  xsrcdir=$srcdir/ ;;
 907   esac
 908   test -n "$enable_debug_configure" &&
 909   echo "[DEBUG]: name/Implies $xsrcdir$name/Implies" >&2
 910
 911   for implies_file in Implies Implies-before Implies-after; do
 912     implies_type=`echo $implies_file | sed s/-/_/`
 913     eval ${implies_type}=
 914     if test -f $xsrcdir$name/$implies_file; then
 915       # Collect more names from the `Implies' file (removing comments).
 916       implied_candidate="`sed 's/#.*$//' < $xsrcdir$name/$implies_file`"
 917       for x in $implied_candidate; do
 918         found=no
 919         if test -d $xsrcdir$name_base/$x; then
 920           eval "${implies_type}=\"\$${implies_type} \$name_base/\$x\""
 921           found=yes
 922         fi
 923         try="sysdeps/$x"
 924         try_srcdir=$srcdir/
 925         test -n "$enable_debug_configure" &&
 926          echo "[DEBUG]: $name $implies_file $x try() {$try_srcdir}$try" >&2
 927         if test $try != $xsrcdir$name_base/$x && test -d $try_srcdir$try;
 928         then
 929           eval "${implies_type}=\"\$${implies_type} \$try\""
 930           found=yes
 931         fi
 932         if test $found = no; then
 933           AC_MSG_WARN($name/$implies_file specifies nonexistent $x)
 934         fi
 935       done
 936     fi
 937   done
 938
 939   # Add NAME to the list of names.
 940   names="$names $name"
 941
 942   # Find the parent of NAME, using the empty string if it has none.
 943 changequote(,)dnl
 944   parent="`echo $name | sed -n -e 's=/[^/]*$==' -e '/sysdeps$/q' -e p`"
 945 changequote([,])dnl
 946
 947   test -n "$enable_debug_configure" &&
 948     echo "[DEBUG]: $name Implies='$Implies' rest='$*' parent='$parent' \
 949 Implies_before='$Implies_before' Implies_after='$Implies_after'" >&2
 950
 951   # Add the names implied by NAME, and NAME's parent (if it has one), to
 952   # the list of names to be processed (the argument list).  We prepend the
 953   # implied names to the list and append the parent.  We want implied
 954   # directories to come before further directories inferred from the
 955   # configuration components; this ensures that for sysv4, unix/common
 956   # (implied by unix/sysv/sysv4) comes before unix/sysv (in ostry (here $*)
 957   # after sysv4).
 958   sysnames="`echo $Implies $* $Implies_before $parent $Implies_after`"
 959   test -n "$sysnames" && set $sysnames
 960 done
 961
 962 # Add the default directories.
 963 default_sysnames="sysdeps/generic"
 964 sysnames="$names $default_sysnames"
 965 AC_SUBST(sysnames)
 966 # The other names were emitted during the scan.
 967 AC_MSG_RESULT($default_sysnames)
 968
 969
 970 ### Locate tools.
 971
 972 AC_PROG_INSTALL
 973 if test "$INSTALL" = "${srcdir}/scripts/install-sh -c"; then
 974   # The makefiles need to use a different form to find it in $srcdir.
 975   INSTALL='\$(..)./scripts/install-sh -c'
 976 fi
 977 AC_PROG_LN_S
 978
 979 LIBC_PROG_BINUTILS
 980
 981 # Accept binutils 2.25 or newer.
 982 AC_CHECK_PROG_VER(AS, $AS, --version,
 983                   [GNU assembler.* \([0-9]*\.[0-9.]*\)],
 984                   [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
 985                   AS=: critic_missing="$critic_missing as")
 986
 987 if test -n "`$LD --version | sed -n 's/^GNU \(gold\).*$/\1/p'`"; then
 988   # Accept gold 1.14 or higher
 989   AC_CHECK_PROG_VER(LD, $LD, --version,
 990                     [GNU gold.* \([0-9][0-9]*\.[0-9.]*\)],
 991                     [1.1[4-9]*|1.[2-9][0-9]*|1.1[0-9][0-9]*|[2-9].*|[1-9][0-9]*],
 992                     LD=: critic_missing="$critic_missing GNU gold")
 993 else
 994   AC_CHECK_PROG_VER(LD, $LD, --version,
 995                     [GNU ld.* \([0-9][0-9]*\.[0-9.]*\)],
 996                     [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
 997                     LD=: critic_missing="$critic_missing GNU ld")
 998 fi
 999
1000 # These programs are version sensitive.
1001 AC_CHECK_TOOL_PREFIX
1002 AC_CHECK_PROG_VER(MAKE, gnumake gmake make, --version,
1003   [GNU Make[^0-9]*\([0-9][0-9.]*\)],
1004   [[4-9].* | [1-9][0-9]*], critic_missing="$critic_missing make")
1005
1006 AC_CHECK_PROG_VER(MSGFMT, gnumsgfmt gmsgfmt msgfmt, --version,
1007   [GNU gettext.* \([0-9]*\.[0-9.]*\)],
1008   [0.10.3[6-9]* | 0.10.[4-9][0-9]* | 0.1[1-9]* | 0.[2-9][0-9]* | [1-9].*],
1009   MSGFMT=: aux_missing="$aux_missing msgfmt")
1010 AC_CHECK_PROG_VER(MAKEINFO, makeinfo, --version,
1011   [GNU texinfo.* \([0-9][0-9.]*\)],
1012   [4.[7-9]*|4.[1-9][0-9]*|[5-9].*],
1013   MAKEINFO=: aux_missing="$aux_missing makeinfo")
1014 AC_CHECK_PROG_VER(SED, sed, --version,
1015   [GNU sed[^0-9]* \([0-9]*\.[0-9.]*\)],
1016   [3.0[2-9]*|3.[1-9]*|[4-9]*],
1017   SED=: aux_missing="$aux_missing sed")
1018 AC_CHECK_PROG_VER(AWK, gawk, --version,
1019   [GNU Awk[^0-9]*\([0-9][0-9.]*\)],
1020   [3.1.[2-9]*|3.[2-9]*|[4-9]*], critic_missing="$critic_missing gawk")
1021 AC_CHECK_PROG_VER(BISON, bison, --version,
1022   [bison (GNU Bison) \([0-9]*\.[0-9.]*\)],
1023   [2.7*|[3-9].*|[1-9][0-9]*], critic_missing="$critic_missing bison")
1024
1025 AC_CACHE_CHECK([if $CC is sufficient to build libc], libc_cv_compiler_ok, [
1026 AC_TRY_COMPILE([], [
1027 #if !defined __GNUC__ || __GNUC__ < 5
1028 #error insufficient compiler
1029 #endif],
1030                [libc_cv_compiler_ok=yes],
1031                [libc_cv_compiler_ok=no])])
1032 AS_IF([test $libc_cv_compiler_ok != yes],
1033       [critic_missing="$critic_missing compiler"])
1034
1035 AC_CHECK_TOOL(NM, nm, false)
1036
1037 if test "x$maintainer" = "xyes"; then
1038   AC_CHECK_PROGS(AUTOCONF, autoconf, no)
1039   case "x$AUTOCONF" in
1040   xno|x|x:) AUTOCONF=no ;;
1041   *)
1042     AC_CACHE_CHECK(dnl
1043   whether $AUTOCONF${ACFLAGS:+ }$ACFLAGS works, libc_cv_autoconf_works, [dnl
1044     if (cd $srcdir; $AUTOCONF $ACFLAGS configure.ac > /dev/null 2>&1); then
1045       libc_cv_autoconf_works=yes
1046     else
1047       libc_cv_autoconf_works=no
1048     fi])
1049     test $libc_cv_autoconf_works = yes || AUTOCONF=no
1050     ;;
1051   esac
1052   if test "x$AUTOCONF" = xno; then
1053     aux_missing="$aux_missing autoconf"
1054   fi
1055 else
1056   AUTOCONF=no
1057 fi
1058
1059 # Check for python3 if available, or else python.
1060 AC_CHECK_PROG_VER(PYTHON_PROG, python3 python, --version,
1061   [Python \([0-9][0-9.]*\)],
1062   [3.[4-9]*|3.[1-9][0-9]*|[4-9].*|[1-9][0-9]*],
1063   critic_missing="$critic_missing python")
1064 PYTHON="$PYTHON_PROG -B"
1065 AC_SUBST(PYTHON)
1066
1067 test -n "$critic_missing" && AC_MSG_ERROR([
1068 *** These critical programs are missing or too old:$critic_missing
1069 *** Check the INSTALL file for required versions.])
1070
1071 test -n "$aux_missing" && AC_MSG_WARN([
1072 *** These auxiliary programs are missing or incompatible versions:$aux_missing
1073 *** some features or tests will be disabled.
1074 *** Check the INSTALL file for required versions.])
1075
1076 # if using special system headers, find out the compiler's sekrit
1077 # header directory and add that to the list.  NOTE: Only does the right
1078 # thing on a system that doesn't need fixincludes.  (Not presently a problem.)
1079 if test -n "$sysheaders"; then
1080   SYSINCLUDES=-nostdinc
1081   for d in include include-fixed; do
1082     i=`$CC -print-file-name="$d"` && test "x$i" != x && test "x$i" != "x$d" &&
1083     SYSINCLUDES="$SYSINCLUDES -isystem $i"
1084   done
1085   SYSINCLUDES="$SYSINCLUDES \
1086 -isystem `echo $sysheaders | sed 's/:/ -isystem /g'`"
1087   if test -n "$CXX"; then
1088     CXX_SYSINCLUDES=
1089     for cxxheaders in `$CXX -v -S -x c++ /dev/null -o /dev/null 2>&1 \
1090     | sed -n -e '1,/#include/d' -e 's/^ \(\/.*\/[cg]++\)/\1/p'`; do
1091       test "x$cxxheaders" != x &&
1092       CXX_SYSINCLUDES="$CXX_SYSINCLUDES -isystem $cxxheaders"
1093     done
1094   fi
1095 fi
1096 AC_SUBST(SYSINCLUDES)
1097 AC_SUBST(CXX_SYSINCLUDES)
1098
1099 # Obtain some C++ header file paths.  This is used to make a local
1100 # copy of those headers in Makerules.
1101 if test -n "$CXX"; then
1102   find_cxx_header () {
1103     echo "#include <$1>" | $CXX -M -MP -x c++ - 2>/dev/null \
1104          | sed -n "\,$1:,{s/:\$//;p}"
1105   }
1106   CXX_CSTDLIB_HEADER="$(find_cxx_header cstdlib)"
1107   CXX_CMATH_HEADER="$(find_cxx_header cmath)"
1108   CXX_BITS_STD_ABS_H="$(find_cxx_header bits/std_abs.h)"
1109 fi
1110 AC_SUBST(CXX_CSTDLIB_HEADER)
1111 AC_SUBST(CXX_CMATH_HEADER)
1112 AC_SUBST(CXX_BITS_STD_ABS_H)
1113
1114 # Test if LD_LIBRARY_PATH contains the notation for the current directory
1115 # since this would lead to problems installing/building glibc.
1116 # LD_LIBRARY_PATH contains the current directory if one of the following
1117 # is true:
1118 # - one of the terminals (":" and ";") is the first or last sign
1119 # - two terminals occur directly after each other
1120 # - the path contains an element with a dot in it
1121 AC_MSG_CHECKING(LD_LIBRARY_PATH variable)
1122 changequote(,)dnl
1123 case ${LD_LIBRARY_PATH} in
1124   [:\;]* | *[:\;] | *[:\;][:\;]* |  *[:\;]. | .[:\;]*| . | *[:\;].[:\;]* )
1125     ld_library_path_setting="contains current directory"
1126     ;;
1127   *)
1128     ld_library_path_setting="ok"
1129     ;;
1130 esac
1131 changequote([,])dnl
1132 AC_MSG_RESULT($ld_library_path_setting)
1133 if test "$ld_library_path_setting" != "ok"; then
1134 AC_MSG_ERROR([
1135 *** LD_LIBRARY_PATH shouldn't contain the current directory when
1136 *** building glibc. Please change the environment variable
1137 *** and run configure again.])
1138 fi
1139
1140 AC_PATH_PROG(BASH_SHELL, bash, no)
1141
1142 AC_PATH_PROG(PERL, perl, no)
1143 if test "$PERL" != no &&
1144    (eval `$PERL -V:apiversion`; test `expr "$apiversion" \< 5` -ne 0); then
1145   PERL=no
1146 fi
1147 AC_PATH_PROG(INSTALL_INFO, install-info, no,
1148              $PATH:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin)
1149
1150 AC_CACHE_CHECK(for .set assembler directive, libc_cv_asm_set_directive, [dnl
1151 cat > conftest.s <<EOF
1152 .text
1153 foo:
1154 .set glibc_conftest_frobozz,foo
1155 .globl glibc_conftest_frobozz
1156 EOF
1157 # The alpha-dec-osf1 assembler gives only a warning for `.set'
1158 # (but it doesn't work), so we must do a linking check to be sure.
1159 cat > conftest1.c <<\EOF
1160 extern int glibc_conftest_frobozz;
1161 void _start() { glibc_conftest_frobozz = 1; }
1162 EOF
1163 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
1164             -nostartfiles -nostdlib $no_ssp \
1165             -o conftest conftest.s conftest1.c 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
1166   libc_cv_asm_set_directive=yes
1167 else
1168   libc_cv_asm_set_directive=no
1169 fi
1170 rm -f conftest*])
1171 if test $libc_cv_asm_set_directive = yes; then
1172   AC_DEFINE(HAVE_ASM_SET_DIRECTIVE)
1173 fi
1174
1175 AC_CACHE_CHECK(linker support for protected data symbol,
1176                libc_cv_protected_data,
1177                [cat > conftest.c <<EOF
1178                 int bar __attribute__ ((visibility ("protected"))) = 1;
1179 EOF
1180                 libc_cv_protected_data=no
1181                 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -o conftest.so); then
1182                   cat > conftest.c <<EOF
1183                   extern int bar;
1184                   int main (void) { return bar; }
1185 EOF
1186                   if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp conftest.c -o conftest conftest.so); then
1187                     libc_cv_protected_data=yes
1188                   fi
1189                 fi
1190                 rm -f conftest.*
1191                ])
1192 AC_SUBST(libc_cv_protected_data)
1193
1194 AC_CACHE_CHECK(linker support for INSERT in linker script,
1195                libc_cv_insert,
1196                [cat > conftest.c <<EOF
1197                 const int __attribute__ ((section(".bar"))) bar = 0x12345678;
1198                 int test (void) { return bar; }
1199 EOF
1200                 cat > conftest.t <<EOF
1201                 SECTIONS
1202                 {
1203                   .bar : { *(.bar) }
1204                 }
1205                 INSERT AFTER .rela.dyn;
1206 EOF
1207                 libc_cv_insert=no
1208                 if AC_TRY_COMMAND([${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -Wl,-T,conftest.t -o conftest.so]); then
1209                   libc_cv_insert=yes
1210                 fi
1211                 rm -f conftest.*
1212                ])
1213 AC_SUBST(libc_cv_insert)
1214
1215 AC_CACHE_CHECK(for broken __attribute__((alias())),
1216                libc_cv_broken_alias_attribute,
1217                [cat > conftest.c <<EOF
1218                extern int foo (int x) __asm ("xyzzy");
1219                int bar (int x) { return x; }
1220                extern __typeof (bar) foo __attribute ((weak, alias ("bar")));
1221                extern int dfoo;
1222                extern __typeof (dfoo) dfoo __asm ("abccb");
1223                int dfoo = 1;
1224 EOF
1225                libc_cv_broken_alias_attribute=yes
1226                if AC_TRY_COMMAND(${CC-cc} -Werror -S conftest.c -o conftest.s 1>&AS_MESSAGE_LOG_FD); then
1227                  if grep 'xyzzy' conftest.s >/dev/null &&
1228                     grep 'abccb' conftest.s >/dev/null; then
1229                    libc_cv_broken_alias_attribute=no
1230                  fi
1231                fi
1232                rm -f conftest.c conftest.s
1233                ])
1234 if test $libc_cv_broken_alias_attribute = yes; then
1235   AC_MSG_ERROR(working alias attribute support required)
1236 fi
1237
1238 AC_CACHE_CHECK(whether to put _rtld_local into .sdata section,
1239                libc_cv_have_sdata_section,
1240                [echo "int i;" > conftest.c
1241                 libc_cv_have_sdata_section=no
1242                 if ${CC-cc} $LDFLAGS -fPIC -shared -Wl,--verbose conftest.c -o conftest.so 2>&1 \
1243                    | grep '\.sdata' >/dev/null; then
1244                   libc_cv_have_sdata_section=yes
1245                 fi
1246                 rm -f conftest.c conftest.so
1247                ])
1248 if test $libc_cv_have_sdata_section = yes; then
1249   AC_DEFINE(HAVE_SDATA_SECTION)
1250 fi
1251
1252 AC_CACHE_CHECK(whether to use .ctors/.dtors header and trailer,
1253                libc_cv_ctors_header, [dnl
1254   libc_cv_ctors_header=yes
1255   LIBC_TRY_LINK_STATIC([
1256 __attribute__ ((constructor)) void ctor (void) { asm (""); }
1257 __attribute__ ((destructor))  void dtor (void) { asm (""); }
1258 ],
1259               [dnl
1260       AS_IF([$READELF -WS conftest$ac_exeext | $AWK '
1261         { gsub(/\@<:@ */, "@<:@") }
1262         $2 == ".ctors" || $2 == ".dtors" {
1263           size = strtonum("0x" $6)
1264           align = strtonum("0x" $NF)
1265           seen@<:@$2@:>@ = 1
1266           stub@<:@$2@:>@ = size == align * 2
1267         }
1268         END {
1269           ctors_ok = !seen@<:@".ctors"@:>@ || stub@<:@".ctors"@:>@
1270           dtors_ok = !seen@<:@".dtors"@:>@ || stub@<:@".dtors"@:>@
1271           exit ((ctors_ok && dtors_ok) ? 0 : 1)
1272         }
1273       '], [libc_cv_ctors_header=no])
1274     ], [dnl
1275       AC_MSG_ERROR([missing __attribute__ ((constructor)) support??])
1276     ])
1277 ])
1278 if test $libc_cv_ctors_header = no; then
1279   AC_DEFINE(NO_CTORS_DTORS_SECTIONS)
1280 fi
1281
1282 AC_CACHE_CHECK(for libunwind-support in compiler,
1283                libc_cv_cc_with_libunwind, [
1284   cat > conftest.c <<EOF
1285 int main (void) { return 0; }
1286 EOF
1287   if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -static -o conftest \
1288      conftest.c -v 2>&1 >/dev/null | grep ' -lunwind ' >/dev/null; then
1289     libc_cv_cc_with_libunwind=yes
1290   else
1291     libc_cv_cc_with_libunwind=no
1292   fi
1293   rm -f conftest*])
1294 AC_SUBST(libc_cv_cc_with_libunwind)
1295 if test $libc_cv_cc_with_libunwind = yes; then
1296   AC_DEFINE(HAVE_CC_WITH_LIBUNWIND)
1297 fi
1298
1299 ASFLAGS_config=
1300 AC_CACHE_CHECK(whether --noexecstack is desirable for .S files,
1301                libc_cv_as_noexecstack, [dnl
1302 cat > conftest.c <<EOF
1303 void foo (void) { }
1304 EOF
1305 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS
1306                    -S -o conftest.s conftest.c 1>&AS_MESSAGE_LOG_FD]) \
1307    && grep .note.GNU-stack conftest.s >/dev/null \
1308    && AC_TRY_COMMAND([${CC-cc} $ASFLAGS -Wa,--noexecstack
1309                       -c -o conftest.o conftest.s 1>&AS_MESSAGE_LOG_FD])
1310 then
1311   libc_cv_as_noexecstack=yes
1312 else
1313   libc_cv_as_noexecstack=no
1314 fi
1315 rm -f conftest*])
1316 if test $libc_cv_as_noexecstack = yes; then
1317   ASFLAGS_config="$ASFLAGS_config -Wa,--noexecstack"
1318 fi
1319 AC_SUBST(ASFLAGS_config)
1320
1321 AC_CACHE_CHECK(for -z combreloc,
1322                libc_cv_z_combreloc, [dnl
1323 cat > conftest.c <<EOF
1324 extern int bar (int);
1325 extern int mumble;
1326 int foo (void) { return bar (mumble); }
1327 EOF
1328 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1329                         -fPIC -shared $no_ssp -o conftest.so conftest.c
1330                         -nostdlib -nostartfiles
1331                         -Wl,-z,combreloc 1>&AS_MESSAGE_LOG_FD])
1332 then
1333 dnl The following test is a bit weak.  We must use a tool which can test
1334 dnl cross-platform since the gcc used can be a cross compiler.  Without
1335 dnl introducing new options this is not easily doable.  Instead use a tool
1336 dnl which always is cross-platform: readelf.  To detect whether -z combreloc
1337 dnl look for a section named .rel.dyn or .rela.dyn.
1338   if $READELF -S conftest.so | grep -E '.rela?.dyn' > /dev/null; then
1339     libc_cv_z_combreloc=yes
1340   else
1341     libc_cv_z_combreloc=no
1342   fi
1343 else
1344   libc_cv_z_combreloc=no
1345 fi
1346 rm -f conftest*])
1347 if test "$libc_cv_z_combreloc" = yes; then
1348   AC_DEFINE(HAVE_Z_COMBRELOC)
1349 fi
1350 AC_SUBST(libc_cv_z_combreloc)
1351
1352 LIBC_LINKER_FEATURE([-z execstack], [-Wl,-z,execstack],
1353                     [libc_cv_z_execstack=yes], [libc_cv_z_execstack=no])
1354 AC_SUBST(libc_cv_z_execstack)
1355
1356 LIBC_LINKER_FEATURE([--no-dynamic-linker],
1357                     [-Wl,--no-dynamic-linker],
1358                     [libc_cv_no_dynamic_linker=yes],
1359                     [libc_cv_no_dynamic_linker=no])
1360 LIBC_CONFIG_VAR([have-no-dynamic-linker], [$libc_cv_no_dynamic_linker])
1361
1362 AC_CACHE_CHECK(for -static-pie, libc_cv_static_pie, [dnl
1363 LIBC_TRY_CC_OPTION([-static-pie],
1364                    [libc_cv_static_pie=yes],
1365                    [libc_cv_static_pie=no])
1366 ])
1367 LIBC_CONFIG_VAR([have-static-pie], [$libc_cv_static_pie])
1368
1369 AC_CACHE_CHECK(for -fpie, libc_cv_fpie, [dnl
1370 LIBC_TRY_CC_OPTION([-fpie], [libc_cv_fpie=yes], [libc_cv_fpie=no])
1371 ])
1372
1373 AC_SUBST(libc_cv_fpie)
1374
1375 AC_CACHE_CHECK(for --hash-style option,
1376                libc_cv_hashstyle, [dnl
1377 cat > conftest.c <<EOF
1378 int _start (void) { return 42; }
1379 EOF
1380 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp
1381                             -fPIC -shared -o conftest.so conftest.c
1382                             -Wl,--hash-style=both -nostdlib 1>&AS_MESSAGE_LOG_FD])
1383 then
1384   libc_cv_hashstyle=yes
1385 else
1386   libc_cv_hashstyle=no
1387 fi
1388 rm -f conftest*])
1389 AC_SUBST(libc_cv_hashstyle)
1390
1391 # The linker's default -shared behavior is good enough if it
1392 # does these things that our custom linker scripts ensure that
1393 # all allocated NOTE sections come first.
1394 if test "$use_default_link" = default; then
1395   AC_CACHE_CHECK([for sufficient default -shared layout],
1396                   libc_cv_use_default_link, [dnl
1397   libc_cv_use_default_link=no
1398   cat > conftest.s <<\EOF
1399           .section .note.a,"a",%note
1400           .balign 4
1401           .long 4,4,9
1402           .string "GNU"
1403           .string "foo"
1404           .section .note.b,"a",%note
1405           .balign 4
1406           .long 4,4,9
1407           .string "GNU"
1408           .string "bar"
1409 EOF
1410   if AC_TRY_COMMAND([dnl
1411   ${CC-cc} $ASFLAGS -shared -o conftest.so conftest.s 1>&AS_MESSAGE_LOG_FD]) &&
1412        ac_try=`$READELF -S conftest.so | sed -n \
1413          ['${x;p;}
1414           s/^ *\[ *[1-9][0-9]*\]  *\([^ ][^ ]*\)  *\([^ ][^ ]*\) .*$/\2 \1/
1415           t a
1416           b
1417           : a
1418           H']`
1419   then
1420     libc_seen_a=no libc_seen_b=no
1421     set -- $ac_try
1422     while test $# -ge 2 -a "$1" = NOTE; do
1423       case "$2" in
1424       .note.a) libc_seen_a=yes ;;
1425       .note.b) libc_seen_b=yes ;;
1426       esac
1427       shift 2
1428     done
1429     case "$libc_seen_a$libc_seen_b" in
1430     yesyes)
1431       libc_cv_use_default_link=yes
1432       ;;
1433     *)
1434       echo >&AS_MESSAGE_LOG_FD "\
1435 $libc_seen_a$libc_seen_b from:
1436 $ac_try"
1437       ;;
1438     esac
1439   fi
1440   rm -f conftest*])
1441   use_default_link=$libc_cv_use_default_link
1442 fi
1443
1444 AC_CACHE_CHECK(for GLOB_DAT reloc,
1445                libc_cv_has_glob_dat, [dnl
1446 cat > conftest.c <<EOF
1447 extern int mumble;
1448 int foo (void) { return mumble; }
1449 EOF
1450 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1451                         -fPIC -shared -o conftest.so conftest.c
1452                         -nostdlib -nostartfiles $no_ssp
1453                         1>&AS_MESSAGE_LOG_FD])
1454 then
1455 dnl look for GLOB_DAT relocation.
1456   if $READELF -rW conftest.so | grep '_GLOB_DAT' > /dev/null; then
1457     libc_cv_has_glob_dat=yes
1458   else
1459     libc_cv_has_glob_dat=no
1460   fi
1461 else
1462   libc_cv_has_glob_dat=no
1463 fi
1464 rm -f conftest*])
1465 AC_SUBST(libc_cv_has_glob_dat)
1466
1467 AC_CACHE_CHECK(linker output format, libc_cv_output_format, [dnl
1468 if libc_cv_output_format=`
1469 ${CC-cc} -nostartfiles -nostdlib $no_ssp -Wl,--print-output-format 2>&AS_MESSAGE_LOG_FD`
1470 then
1471   :
1472 else
1473   libc_cv_output_format=
1474 fi
1475 test -n "$libc_cv_output_format" || libc_cv_output_format=unknown])
1476 AC_SUBST(libc_cv_output_format)
1477
1478 AC_CACHE_CHECK(for -fno-toplevel-reorder -fno-section-anchors, libc_cv_fno_toplevel_reorder, [dnl
1479 cat > conftest.c <<EOF
1480 int foo;
1481 EOF
1482 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fno-toplevel-reorder -fno-section-anchors
1483                             conftest.c 1>&AS_MESSAGE_LOG_FD])
1484 then
1485   libc_cv_fno_toplevel_reorder=yes
1486 else
1487   libc_cv_fno_toplevel_reorder=no
1488 fi
1489 rm -f conftest*])
1490 if test $libc_cv_fno_toplevel_reorder = yes; then
1491   fno_unit_at_a_time="-fno-toplevel-reorder -fno-section-anchors"
1492 else
1493   fno_unit_at_a_time=-fno-unit-at-a-time
1494 fi
1495 AC_SUBST(fno_unit_at_a_time)
1496
1497 AC_CACHE_CHECK([for -mtls-dialect=gnu2], libc_cv_mtls_dialect_gnu2,
1498 [dnl
1499 cat > conftest.c <<EOF
1500 __thread int i;
1501 void foo (void)
1502 {
1503   i = 10;
1504 }
1505 EOF
1506 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fPIC -mtls-dialect=gnu2
1507                    conftest.c 1>&AS_MESSAGE_LOG_FD])
1508 then
1509   libc_cv_mtls_dialect_gnu2=yes
1510 else
1511   libc_cv_mtls_dialect_gnu2=no
1512 fi
1513 rm -f conftest*])
1514 AC_SUBST(libc_cv_mtls_dialect_gnu2)
1515 LIBC_CONFIG_VAR([have-mtls-dialect-gnu2], [$libc_cv_mtls_dialect_gnu2])
1516
1517 AC_CACHE_CHECK(whether cc puts quotes around section names,
1518                libc_cv_have_section_quotes,
1519                [cat > conftest.c <<EOF
1520                 static const int foo
1521                 __attribute__ ((section ("bar"))) = 1;
1522 EOF
1523                 if ${CC-cc} -S conftest.c -o conftest.s; then
1524                   if grep '\.section.*"bar"' conftest.s >/dev/null; then
1525                     libc_cv_have_section_quotes=yes
1526                   else
1527                     libc_cv_have_section_quotes=no
1528                   fi
1529                 else
1530                   libc_cv_have_section_quotes=unknown
1531                 fi
1532                 rm -f conftest.{c,s}
1533                 ])
1534 if test $libc_cv_have_section_quotes = yes; then
1535   AC_DEFINE(HAVE_SECTION_QUOTES)
1536 fi
1537
1538 AC_CACHE_CHECK(for __builtin_memset, libc_cv_gcc_builtin_memset, [dnl
1539 cat > conftest.c <<\EOF
1540 void zero (void *x)
1541 {
1542   __builtin_memset (x, 0, 1000);
1543 }
1544 EOF
1545 dnl
1546 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "memset" > /dev/null]);
1547 then
1548   libc_cv_gcc_builtin_memset=no
1549 else
1550   libc_cv_gcc_builtin_memset=yes
1551 fi
1552 rm -f conftest* ])
1553 if test "$libc_cv_gcc_builtin_memset" = yes ; then
1554   AC_DEFINE(HAVE_BUILTIN_MEMSET)
1555 fi
1556
1557 AC_CACHE_CHECK(for redirection of built-in functions, libc_cv_gcc_builtin_redirection, [dnl
1558 cat > conftest.c <<\EOF
1559 extern char *strstr (const char *, const char *) __asm ("my_strstr");
1560 char *foo (const char *a, const char *b)
1561 {
1562   return __builtin_strstr (a, b);
1563 }
1564 EOF
1565 dnl
1566 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "my_strstr" > /dev/null]);
1567 then
1568   libc_cv_gcc_builtin_redirection=yes
1569 else
1570   libc_cv_gcc_builtin_redirection=no
1571 fi
1572 rm -f conftest* ])
1573 if test "$libc_cv_gcc_builtin_redirection" = no; then
1574   AC_MSG_ERROR([support for the symbol redirection needed])
1575 fi
1576
1577 dnl Determine how to disable generation of FMA instructions.
1578 AC_CACHE_CHECK([for compiler option to disable generation of FMA instructions],
1579                libc_cv_cc_nofma, [dnl
1580 libc_cv_cc_nofma=
1581 for opt in -ffp-contract=off -mno-fused-madd; do
1582   LIBC_TRY_CC_OPTION([$opt], [libc_cv_cc_nofma=$opt; break])
1583 done])
1584 AC_SUBST(libc_cv_cc_nofma)
1585
1586 if test -n "$submachine"; then
1587   AC_CACHE_CHECK([for compiler option for CPU variant],
1588                  libc_cv_cc_submachine, [dnl
1589   libc_cv_cc_submachine=no
1590   for opt in "-march=$submachine" "-mcpu=$submachine"; do
1591     LIBC_TRY_CC_OPTION([$opt], [
1592       libc_cv_cc_submachine="$opt"
1593       break], [])
1594   done])
1595   if test "x$libc_cv_cc_submachine" = xno; then
1596     AC_MSG_ERROR([${CC-cc} does not support $submachine])
1597   fi
1598 fi
1599 AC_SUBST(libc_cv_cc_submachine)
1600
1601 AC_CACHE_CHECK(if $CC accepts -fno-tree-loop-distribute-patterns with \
1602 __attribute__ ((__optimize__)), libc_cv_cc_loop_to_function, [dnl
1603 cat > conftest.c <<EOF
1604 void
1605 __attribute__ ((__optimize__ ("-fno-tree-loop-distribute-patterns")))
1606 foo (void) {}
1607 EOF
1608 libc_cv_cc_loop_to_function=no
1609 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -c conftest.c])
1610 then
1611   libc_cv_cc_loop_to_function=yes
1612 fi
1613 rm -f conftest*])
1614 if test $libc_cv_cc_loop_to_function = yes; then
1615   AC_DEFINE(HAVE_CC_INHIBIT_LOOP_TO_LIBCALL)
1616 fi
1617 AC_SUBST(libc_cv_cc_loop_to_function)
1618
1619 dnl Check whether we have the gd library available.
1620 AC_MSG_CHECKING(for libgd)
1621 if test "$with_gd" != "no"; then
1622   old_CFLAGS="$CFLAGS"
1623   CFLAGS="$CFLAGS $libgd_include"
1624   old_LDFLAGS="$LDFLAGS"
1625   LDFLAGS="$LDFLAGS $libgd_ldflags"
1626   old_LIBS="$LIBS"
1627   LIBS="$LIBS -lgd -lpng -lz -lm"
1628   AC_TRY_LINK([#include <gd.h>], [gdImagePng (0, 0)], LIBGD=yes, LIBGD=no)
1629   CFLAGS="$old_CFLAGS"
1630   LDFLAGS="$old_LDFLAGS"
1631   LIBS="$old_LIBS"
1632 else
1633   LIBGD=no
1634 fi
1635 AC_MSG_RESULT($LIBGD)
1636 AC_SUBST(LIBGD)
1637
1638 # SELinux detection
1639 if test x$with_selinux = xno ; then
1640   have_selinux=no;
1641 else
1642   # See if we have the SELinux library
1643   AC_CHECK_LIB(selinux, is_selinux_enabled,
1644                have_selinux=yes, have_selinux=no)
1645   if test x$with_selinux = xyes ; then
1646     if test x$have_selinux = xno ; then
1647       AC_MSG_ERROR([SELinux explicitly required, but SELinux library not found])
1648     fi
1649   fi
1650 fi
1651 # Check if we're building with SELinux support.
1652 if test "x$have_selinux" = xyes; then
1653   AC_DEFINE(HAVE_SELINUX, 1, [SELinux support])
1654
1655   # See if we have the libaudit library
1656   AC_CHECK_LIB(audit, audit_log_user_avc_message,
1657                have_libaudit=yes, have_libaudit=no)
1658   if test "x$have_libaudit" = xyes; then
1659     AC_DEFINE(HAVE_LIBAUDIT, 1, [SELinux libaudit support])
1660   fi
1661   AC_SUBST(have_libaudit)
1662
1663   # See if we have the libcap library
1664   AC_CHECK_LIB(cap, cap_init, have_libcap=yes, have_libcap=no)
1665   if test "x$have_libcap" = xyes; then
1666     AC_DEFINE(HAVE_LIBCAP, 1, [SELinux libcap support])
1667   fi
1668   AC_SUBST(have_libcap)
1669 fi
1670 AC_SUBST(have_selinux)
1671
1672 CPPUNDEFS=
1673 dnl Check for silly hacked compilers predefining _FORTIFY_SOURCE.
1674 dnl Since we are building the implementations of the fortified functions here,
1675 dnl having the macro defined interacts very badly.
1676 AC_CACHE_CHECK([for _FORTIFY_SOURCE predefine], libc_cv_predef_fortify_source,
1677 [AC_TRY_COMPILE([], [
1678 #ifdef _FORTIFY_SOURCE
1679 # error bogon
1680 #endif],
1681                 [libc_cv_predef_fortify_source=no],
1682                 [libc_cv_predef_fortify_source=yes])])
1683 if test $libc_cv_predef_fortify_source = yes; then
1684   CPPUNDEFS="${CPPUNDEFS:+$CPPUNDEFS }-U_FORTIFY_SOURCE"
1685 fi
1686 AC_SUBST(CPPUNDEFS)
1687
1688 # Some linkers on some architectures support __ehdr_start but with
1689 # bugs.  Make sure usage of it does not create relocations in the
1690 # output (as the linker should resolve them all for us).
1691 AC_CACHE_CHECK([whether the linker provides working __ehdr_start],
1692                libc_cv_ehdr_start, [
1693 old_CFLAGS="$CFLAGS"
1694 old_LDFLAGS="$LDFLAGS"
1695 old_LIBS="$LIBS"
1696 CFLAGS="$CFLAGS -fPIC"
1697 LDFLAGS="$LDFLAGS -nostdlib -nostartfiles -shared $no_ssp"
1698 LIBS=
1699 AC_LINK_IFELSE([AC_LANG_SOURCE([
1700 typedef struct {
1701   char foo;
1702   long val;
1703 } Ehdr;
1704 extern const Ehdr __ehdr_start __attribute__ ((visibility ("hidden")));
1705 long ehdr (void) { return __ehdr_start.val; }
1706 ])],
1707                [if $READELF -r conftest | grep -F __ehdr_start >/dev/null; then
1708                   libc_cv_ehdr_start=broken
1709                 else
1710                   libc_cv_ehdr_start=yes
1711                 fi], [libc_cv_ehdr_start=no])
1712 CFLAGS="$old_CFLAGS"
1713 LDFLAGS="$old_LDFLAGS"
1714 LIBS="$old_LIBS"
1715 ])
1716 if test "$libc_cv_ehdr_start" = yes; then
1717   AC_DEFINE([HAVE_EHDR_START])
1718 elif test "$libc_cv_ehdr_start" = broken; then
1719   AC_MSG_WARN([linker is broken -- you should upgrade])
1720 fi
1721
1722 AC_CACHE_CHECK(for __builtin_trap with no external dependencies,
1723                libc_cv_builtin_trap, [dnl
1724 libc_cv_builtin_trap=no
1725 AC_TRY_COMPILE([], [__builtin_trap ()], [
1726 libc_undefs=`$NM -u conftest.o |
1727   LC_ALL=C $AWK '$1 == "U" { print $2 | "sort -u"; next } { exit(1) }' \
1728     2>&AS_MESSAGE_LOG_FD` || {
1729   AC_MSG_ERROR([confusing output from $NM -u])
1730 }
1731 echo >&AS_MESSAGE_LOG_FD "libc_undefs='$libc_undefs'"
1732 if test -z "$libc_undefs"; then
1733   libc_cv_builtin_trap=yes
1734 fi])])
1735 if test $libc_cv_builtin_trap = yes; then
1736   AC_DEFINE([HAVE_BUILTIN_TRAP])
1737 fi
1738
1739 dnl C++ feature tests.
1740 AC_LANG_PUSH([C++])
1741
1742 AC_CACHE_CHECK([whether the C++ compiler supports thread_local],
1743                libc_cv_cxx_thread_local, [
1744 old_CXXFLAGS="$CXXFLAGS"
1745 CXXFLAGS="$CXXFLAGS -std=gnu++11"
1746 AC_COMPILE_IFELSE([AC_LANG_SOURCE([
1747 #include <thread>
1748
1749 // Compiler support.
1750 struct S
1751 {
1752   S ();
1753   ~S ();
1754 };
1755 thread_local S s;
1756 S * get () { return &s; }
1757
1758 // libstdc++ support.
1759 #ifndef _GLIBCXX_HAVE___CXA_THREAD_ATEXIT_IMPL
1760 #error __cxa_thread_atexit_impl not supported
1761 #endif
1762 ])],
1763                [libc_cv_cxx_thread_local=yes],
1764                [libc_cv_cxx_thread_local=no])
1765 CXXFLAGS="$old_CXXFLAGS"
1766 ])
1767 AC_SUBST(libc_cv_cxx_thread_local)
1768
1769 AC_LANG_POP([C++])
1770 dnl End of C++ feature tests.
1771
1772 ### End of automated tests.
1773 ### Now run sysdeps configure fragments.
1774
1775 # They also can set these variables.
1776 use_ldconfig=no
1777 ldd_rewrite_script=no
1778 libc_cv_sysconfdir=$sysconfdir
1779 libc_cv_localstatedir=$localstatedir
1780 libc_cv_gcc_unwind_find_fde=no
1781 libc_cv_idn=no
1782
1783 # Iterate over all the sysdep directories we will use, running their
1784 # configure fragments.
1785 for dir in $sysnames; do
1786   case $dir in
1787     /*) dest=$dir ;;
1788     *)  dest=$srcdir/$dir ;;
1789   esac
1790   if test -r $dest/configure; then
1791     AC_MSG_RESULT(running configure fragment for $dir)
1792     . $dest/configure
1793   fi
1794 done
1795
1796 if test x"$build_mathvec" = xnotset; then
1797   build_mathvec=no
1798 fi
1799 LIBC_CONFIG_VAR([build-mathvec], [$build_mathvec])
1800
1801 AC_SUBST(libc_extra_cflags)
1802 AC_SUBST(libc_extra_cppflags)
1803
1804 if test x$libc_cv_gcc_unwind_find_fde = xyes; then
1805   AC_DEFINE(EXPORT_UNWIND_FIND_FDE)
1806 fi
1807 AC_SUBST(libc_cv_gcc_unwind_find_fde)
1808
1809 # A sysdeps configure fragment can reset this if IFUNC is not actually
1810 # usable even though the assembler knows how to generate the symbol type.
1811 if test x"$libc_cv_ld_gnu_indirect_function" = xyes; then
1812   AC_DEFINE(HAVE_IFUNC)
1813 fi
1814
1815 if test x"$libc_cv_gcc_indirect_function" = xyes; then
1816   AC_DEFINE(HAVE_GCC_IFUNC)
1817 fi
1818
1819 # This is far from the AC_ARG_ENABLE that sets it so that a sysdeps
1820 # configure fragment can override the value to prevent this AC_DEFINE.
1821 AC_SUBST(use_nscd)
1822 if test "x$use_nscd" != xno; then
1823   AC_DEFINE([USE_NSCD])
1824 fi
1825 if test "x$build_nscd" = xdefault; then
1826   build_nscd=$use_nscd
1827 fi
1828
1829 AC_SUBST(libc_cv_slibdir)
1830 AC_SUBST(libc_cv_rtlddir)
1831 AC_SUBST(libc_cv_complocaledir)
1832 AC_SUBST(libc_cv_sysconfdir)
1833 AC_SUBST(libc_cv_localstatedir)
1834 AC_SUBST(libc_cv_rootsbindir)
1835
1836 if test x$use_ldconfig = xyes; then
1837   AC_DEFINE(USE_LDCONFIG)
1838 fi
1839 AC_SUBST(use_ldconfig)
1840 AC_SUBST(ldd_rewrite_script)
1841
1842 AC_SUBST(static)
1843 AC_SUBST(shared)
1844
1845 AC_CACHE_CHECK([whether -fPIC is default], libc_cv_pic_default,
1846 [libc_cv_pic_default=yes
1847 cat > conftest.c <<EOF
1848 #if defined __PIC__ || defined __pic__ || defined PIC || defined pic
1849 # error PIC is default.
1850 #endif
1851 EOF
1852 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1853   libc_cv_pic_default=no
1854 fi
1855 rm -f conftest.*])
1856 AC_SUBST(libc_cv_pic_default)
1857
1858 AC_CACHE_CHECK([whether -fPIE is default], libc_cv_cc_pie_default,
1859 [libc_cv_cc_pie_default=yes
1860 cat > conftest.c <<EOF
1861 #if defined __PIE__ || defined __pie__ || defined PIE || defined pie
1862 # error PIE is default.
1863 #endif
1864 EOF
1865 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1866   libc_cv_cc_pie_default=no
1867 fi
1868 rm -f conftest.*])
1869 libc_cv_pie_default=$libc_cv_cc_pie_default
1870 AC_SUBST(libc_cv_cc_pie_default)
1871 AC_SUBST(libc_cv_pie_default)
1872
1873 # Set the `multidir' variable by grabbing the variable from the compiler.
1874 # We do it once and save the result in a generated makefile.
1875 libc_cv_multidir=`${CC-cc} $CFLAGS $CPPFLAGS -print-multi-directory`
1876 AC_SUBST(libc_cv_multidir)
1877
1878 if test "$static_pie" = yes; then
1879   # The linker must support --no-dynamic-linker.
1880   if test "$libc_cv_no_dynamic_linker" != yes; then
1881     AC_MSG_ERROR([linker support for --no-dynamic-linker needed])
1882   fi
1883   # Default to PIE.
1884   libc_cv_pie_default=yes
1885   AC_DEFINE(ENABLE_STATIC_PIE)
1886 fi
1887 LIBC_CONFIG_VAR([enable-static-pie], [$static_pie])
1888
1889 AC_SUBST(profile)
1890 AC_SUBST(static_nss)
1891
1892 AC_SUBST(DEFINES)
1893
1894 dnl See sysdeps/mach/configure.ac for this variable.
1895 AC_SUBST(mach_interface_list)
1896
1897 VERSION=`sed -n -e 's/^#define VERSION "\([^"]*\)"/\1/p' < $srcdir/version.h`
1898 RELEASE=`sed -n -e 's/^#define RELEASE "\([^"]*\)"/\1/p' < $srcdir/version.h`
1899 AC_SUBST(VERSION)
1900 AC_SUBST(RELEASE)
1901
1902 AC_CONFIG_FILES([config.make Makefile])
1903 AC_CONFIG_COMMANDS([default],[[
1904 case $CONFIG_FILES in *config.make*)
1905 echo "$config_vars" >> config.make;;
1906 esac
1907 test -d bits || mkdir bits]],[[config_vars='$config_vars']])
1908 AC_OUTPUT