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/],
4 [glibc], [https://www.gnu.org/software/glibc/])
5 AC_CONFIG_SRCDIR([include/features.h])
6 AC_CONFIG_HEADERS([config.h])
7 AC_CONFIG_AUX_DIR([scripts])
9 ACX_PKGVERSION([GNU libc])
10 ACX_BUGURL([https://www.gnu.org/software/libc/bugs.html])
11 AC_DEFINE_UNQUOTED([PKGVERSION], ["$PKGVERSION"],
12 [Package description])
13 AC_DEFINE_UNQUOTED([REPORT_BUGS_TO], ["$REPORT_BUGS_TO"],
14 [Bug reporting address])
16 # Glibc should not depend on any header files
17 AC_DEFUN([_AC_INCLUDES_DEFAULT_REQUIREMENTS],
18 [m4_divert_text([DEFAULTS],
19 [ac_includes_default='/* none */'])])
21 # We require GCC, and by default use its preprocessor. Override AC_PROG_CPP
22 # here to work around the Autoconf issue discussed in
23 # <https://sourceware.org/ml/libc-alpha/2013-01/msg00721.html>.
24 AC_DEFUN([AC_PROG_CPP],
25 [AC_REQUIRE([AC_PROG_CC])dnl
26 AC_ARG_VAR([CPP], [C preprocessor])dnl
27 _AC_ARG_VAR_CPPFLAGS()dnl
28 # On Suns, sometimes $CPP names a directory.
29 if test -n "$CPP" && test -d "$CPP"; then
32 if test -z "$CPP"; then
38 # We require GCC. Override _AC_PROG_CC_C89 here to work around the Autoconf
40 # <https://sourceware.org/ml/libc-alpha/2013-01/msg00757.html>.
41 AC_DEFUN([_AC_PROG_CC_C89], [[$1]])
43 dnl This is here so we can set $subdirs directly based on configure fragments.
49 if test $host != $build; then
50 AC_CHECK_PROGS(BUILD_CC, gcc cc)
52 AC_SUBST(cross_compiling)
54 AC_CHECK_TOOL(READELF, readelf, false)
56 # We need the C++ compiler only for testing.
58 # It's useless to us if it can't link programs (e.g. missing -lstdc++).
59 AC_CACHE_CHECK([whether $CXX can link programs], libc_cv_cxx_link_ok, [dnl
61 # Default, dynamic case.
62 AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
63 [libc_cv_cxx_link_ok=yes],
64 [libc_cv_cxx_link_ok=no])
66 old_LDFLAGS="$LDFLAGS"
67 LDFLAGS="$LDFLAGS -static"
68 AC_LINK_IFELSE([AC_LANG_SOURCE([
74 std::cout << "Hello, world!";
79 [libc_cv_cxx_link_ok=no])
80 LDFLAGS="$old_LDFLAGS"
82 AS_IF([test $libc_cv_cxx_link_ok != yes], [CXX=])
84 if test "`cd $srcdir; pwd -P`" = "`pwd -P`"; then
85 AC_MSG_ERROR([you must configure in a separate build directory])
88 # This will get text that should go into config.make.
91 # Check for a --with-gd argument and set libgd-LDFLAGS in config.make.
93 AC_HELP_STRING([--with-gd=DIR],
94 [find libgd include dir and library with prefix DIR]),
98 *) libgd_include="-I$withval/include"
99 libgd_ldflags="-L$withval/lib" ;;
102 AC_ARG_WITH([gd-include],
103 AC_HELP_STRING([--with-gd-include=DIR],
104 [find libgd include files in DIR]),
106 case "$with_gd_include" in
108 *) libgd_include="-I$withval" ;;
111 AC_ARG_WITH([gd-lib],
112 AC_HELP_STRING([--with-gd-lib=DIR],
113 [find libgd library files in DIR]),
115 case "$with_gd_lib" in
117 *) libgd_ldflags="-L$withval" ;;
121 if test -n "$libgd_include"; then
122 config_vars="$config_vars
123 CFLAGS-memusagestat.c = $libgd_include"
125 if test -n "$libgd_ldflags"; then
126 config_vars="$config_vars
127 libgd-LDFLAGS = $libgd_ldflags"
130 dnl Arguments to specify presence of other packages/features.
131 AC_ARG_WITH([binutils],
132 AC_HELP_STRING([--with-binutils=PATH],
133 [specify location of binutils (as and ld)]),
134 [path_binutils=$withval],
136 AC_ARG_WITH([selinux],
137 AC_HELP_STRING([--with-selinux],
138 [if building with SELinux support]),
139 [with_selinux=$withval],
142 AC_ARG_WITH([headers],
143 AC_HELP_STRING([--with-headers=PATH],
144 [location of system headers to use
145 (for example /usr/src/linux/include)
146 @<:@default=compiler default@:>@]),
147 [sysheaders=$withval],
151 AC_SUBST(use_default_link)
152 AC_ARG_WITH([default-link],
153 AC_HELP_STRING([--with-default-link],
154 [do not use explicit linker scripts]),
155 [use_default_link=$withval],
156 [use_default_link=default])
158 dnl Additional build flags injection.
159 AC_ARG_WITH([nonshared-cflags],
160 AC_HELP_STRING([--with-nonshared-cflags=CFLAGS],
161 [build nonshared libraries with additional CFLAGS]),
162 [extra_nonshared_cflags=$withval],
163 [extra_nonshared_cflags=])
164 AC_SUBST(extra_nonshared_cflags)
166 AC_ARG_ENABLE([sanity-checks],
167 AC_HELP_STRING([--disable-sanity-checks],
168 [really do not use threads (should not be used except in special situations) @<:@default=yes@:>@]),
169 [enable_sanity=$enableval],
172 AC_ARG_ENABLE([shared],
173 AC_HELP_STRING([--enable-shared],
174 [build shared library @<:@default=yes if GNU ld@:>@]),
177 AC_ARG_ENABLE([profile],
178 AC_HELP_STRING([--enable-profile],
179 [build profiled library @<:@default=no@:>@]),
180 [profile=$enableval],
182 AC_ARG_ENABLE([static-pie],
183 AC_HELP_STRING([--enable-static-pie],
184 [enable static PIE support and use it in the testsuite @<:@default=no@:>@]),
185 [static_pie=$enableval],
187 AC_ARG_ENABLE([timezone-tools],
188 AC_HELP_STRING([--disable-timezone-tools],
189 [do not install timezone tools @<:@default=install@:>@]),
190 [enable_timezone_tools=$enableval],
191 [enable_timezone_tools=yes])
192 AC_SUBST(enable_timezone_tools)
194 AC_ARG_ENABLE([hardcoded-path-in-tests],
195 AC_HELP_STRING([--enable-hardcoded-path-in-tests],
196 [hardcode newly built glibc path in tests @<:@default=no@:>@]),
197 [hardcoded_path_in_tests=$enableval],
198 [hardcoded_path_in_tests=no])
199 AC_SUBST(hardcoded_path_in_tests)
201 AC_ARG_ENABLE([stackguard-randomization],
202 AC_HELP_STRING([--enable-stackguard-randomization],
203 [initialize __stack_chk_guard canary with a random number at program start]),
204 [enable_stackguard_randomize=$enableval],
205 [enable_stackguard_randomize=no])
206 if test "$enable_stackguard_randomize" = yes; then
207 AC_DEFINE(ENABLE_STACKGUARD_RANDOMIZE)
210 AC_ARG_ENABLE([hidden-plt],
211 AC_HELP_STRING([--disable-hidden-plt],
212 [do not hide internal function calls to avoid PLT]),
215 if test "x$hidden" = xno; then
219 AC_ARG_ENABLE([bind-now],
220 AC_HELP_STRING([--enable-bind-now],
221 [disable lazy relocations in DSOs]),
222 [bindnow=$enableval],
225 if test "x$bindnow" = xyes; then
229 dnl Build glibc with -fstack-protector, -fstack-protector-all, or
230 dnl -fstack-protector-strong.
231 AC_ARG_ENABLE([stack-protector],
232 AC_HELP_STRING([--enable-stack-protector=@<:@yes|no|all|strong@:>@],
233 [Use -fstack-protector[-all|-strong] to detect glibc buffer overflows]),
234 [enable_stack_protector=$enableval],
235 [enable_stack_protector=no])
236 case "$enable_stack_protector" in
237 all|yes|no|strong) ;;
238 *) AC_MSG_ERROR([Not a valid argument for --enable-stack-protector: \"$enable_stack_protector\"]);;
241 dnl On some platforms we cannot use dynamic loading. We must provide
242 dnl static NSS modules.
243 AC_ARG_ENABLE([static-nss],
244 AC_HELP_STRING([--enable-static-nss],
245 [build static NSS modules @<:@default=no@:>@]),
246 [static_nss=$enableval],
248 dnl Enable static NSS also if we build no shared objects.
249 if test x"$static_nss" = xyes || test x"$shared" = xno; then
251 AC_DEFINE(DO_STATIC_NSS)
254 AC_ARG_ENABLE([force-install],
255 AC_HELP_STRING([--disable-force-install],
256 [don't force installation of files from this package, even if they are older than the installed files]),
257 [force_install=$enableval],
259 AC_SUBST(force_install)
261 AC_ARG_ENABLE([maintainer-mode],
262 AC_HELP_STRING([--enable-maintainer-mode],
263 [enable make rules and dependencies not useful (and sometimes confusing) to the casual installer]),
264 [maintainer=$enableval],
267 dnl On some platforms we allow dropping compatibility with all kernel
269 AC_ARG_ENABLE([kernel],
270 AC_HELP_STRING([--enable-kernel=VERSION],
271 [compile for compatibility with kernel not older than VERSION]),
272 [minimum_kernel=$enableval],
274 dnl Prevent unreasonable values.
275 if test "$minimum_kernel" = yes || test "$minimum_kernel" = no; then
276 # Better nothing than this.
279 if test "$minimum_kernel" = current; then
280 minimum_kernel=`uname -r 2>/dev/null` || minimum_kernel=
284 dnl For the development we sometimes want gcc to issue even more warnings.
285 dnl This is not the default since many of the extra warnings are not
287 AC_ARG_ENABLE([all-warnings],
288 AC_HELP_STRING([--enable-all-warnings],
289 [enable all useful warnings gcc can issue]),
290 [all_warnings=$enableval],
292 AC_SUBST(all_warnings)
294 AC_ARG_ENABLE([werror],
295 AC_HELP_STRING([--disable-werror],
296 [do not build with -Werror]),
297 [enable_werror=$enableval],
299 AC_SUBST(enable_werror)
301 AC_ARG_ENABLE([multi-arch],
302 AC_HELP_STRING([--enable-multi-arch],
303 [enable single DSO with optimizations for multiple architectures]),
304 [multi_arch=$enableval],
305 [multi_arch=default])
307 AC_ARG_ENABLE([experimental-malloc],
308 AC_HELP_STRING([--disable-experimental-malloc],
309 [disable experimental malloc features]),
310 [experimental_malloc=$enableval],
311 [experimental_malloc=yes])
312 AC_SUBST(experimental_malloc)
314 AC_ARG_ENABLE([memory-tagging],
315 AC_HELP_STRING([--enable-memory-tagging],
316 [enable memory tagging if supported by the architecture @<:@default=no@:>@]),
317 [memory_tagging=$enableval],
319 if test "$memory_tagging" = yes; then
320 # Only enable this on architectures that support it.
327 AC_SUBST(memory_tagging)
329 AC_ARG_ENABLE([crypt],
330 AC_HELP_STRING([--disable-crypt],
331 [do not build nor install the passphrase hashing library, libcrypt]),
332 [build_crypt=$enableval],
334 AC_SUBST(build_crypt)
336 AC_ARG_ENABLE([nss-crypt],
337 AC_HELP_STRING([--enable-nss-crypt],
338 [enable libcrypt to use nss]),
339 [nss_crypt=$enableval],
341 if test x$build_libcrypt = xno && test x$nss_crypt = xyes; then
342 AC_MSG_WARN([--enable-nss-crypt has no effect when libcrypt is disabled])
345 if test x$nss_crypt = xyes; then
346 nss_includes=-I$(nss-config --includedir 2>/dev/null)
347 if test $? -ne 0; then
348 AC_MSG_ERROR([cannot find include directory with nss-config])
350 nspr_includes=-I$(nspr-config --includedir 2>/dev/null)
351 if test $? -ne 0; then
352 AC_MSG_ERROR([cannot find include directory with nspr-config])
355 CFLAGS="$CFLAGS $nss_includes $nspr_includes"
356 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
358 #include <nsslowhash.h>
359 void f (void) { NSSLOW_Init (); }])],
360 libc_cv_nss_crypt=yes,
362 cannot find NSS headers with lowlevel hash function interfaces]))
364 old_LDFLAGS="$LDFLAGS"
365 LIBS="$LIBS -lfreebl3"
366 AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
368 #include <nsslowhash.h>],
370 libc_cv_nss_crypt=yes,
372 cannot link program using lowlevel NSS hash functions]))
373 # Check to see if there is a static NSS cryptographic library.
374 # If there isn't then we can't link anything with libcrypt.a,
375 # and that might mean disabling some static tests.
376 LDFLAGS="$LDFLAGS -static"
377 AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
379 #include <nsslowhash.h>],
381 libc_cv_static_nss_crypt=yes,
382 libc_cv_static_nss_crypt=no)
383 LDFLAGS="$old_LDFLAGS"
388 libc_cv_static_nss_crypt=no
390 AC_SUBST(libc_cv_nss_crypt)
391 AC_SUBST(libc_cv_static_nss_crypt)
394 AC_ARG_ENABLE([systemtap],
395 [AS_HELP_STRING([--enable-systemtap],
396 [enable systemtap static probe points @<:@default=no@:>@])],
397 [systemtap=$enableval],
399 if test "x$systemtap" != xno; then
400 AC_CACHE_CHECK([for systemtap static probe support], libc_cv_sdt, [dnl
402 CFLAGS="-std=gnu11 $CFLAGS"
403 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <sys/sdt.h>
404 void foo (int i, void *p)
406 asm ("" STAP_PROBE_ASM (foo, bar, STAP_PROBE_ASM_TEMPLATE (2)) ""
407 :: STAP_PROBE_ASM_OPERANDS (2, i, p));
408 }]])], [libc_cv_sdt=yes], [libc_cv_sdt=no])
409 CFLAGS="$old_CFLAGS"])
410 if test $libc_cv_sdt = yes; then
411 AC_DEFINE([USE_STAP_PROBE])
412 elif test "x$systemtap" != xauto; then
413 AC_MSG_FAILURE([systemtap support needs sys/sdt.h with asm support])
417 AC_ARG_ENABLE([build-nscd],
418 [AS_HELP_STRING([--disable-build-nscd],
419 [disable building and installing the nscd daemon])],
420 [build_nscd=$enableval],
421 [build_nscd=default])
424 # Note the use of $use_nscd is near the bottom of the file.
425 AC_ARG_ENABLE([nscd],
426 [AS_HELP_STRING([--disable-nscd],
427 [library functions will not contact the nscd daemon])],
428 [use_nscd=$enableval],
431 AC_ARG_ENABLE([pt_chown],
432 [AS_HELP_STRING([--enable-pt_chown],
433 [Enable building and installing pt_chown])],
434 [build_pt_chown=$enableval],
436 AC_SUBST(build_pt_chown)
437 if test "$build_pt_chown" = yes; then
438 AC_DEFINE(HAVE_PT_CHOWN)
441 AC_ARG_ENABLE([tunables],
442 [AS_HELP_STRING([--enable-tunables],
443 [Enable tunables support. Known values are 'yes', 'no' and 'valstring'])],
444 [have_tunables=$enableval],
446 AC_SUBST(have_tunables)
447 if test "$have_tunables" = yes; then
448 AC_DEFINE(HAVE_TUNABLES)
451 # The abi-tags file uses a fairly simplistic model for name recognition that
452 # can't distinguish i486-pc-linux-gnu fully from i486-pc-gnu. So we mutate a
453 # $host_os of `gnu*' here to be `gnu-gnu*' just so that it can tell.
454 # This doesn't get used much beyond that, so it's fairly safe.
459 host_os=`echo $host_os | sed -e 's/gnu/gnu-gnu/'`
463 AC_ARG_ENABLE([mathvec],
464 [AS_HELP_STRING([--enable-mathvec],
465 [Enable building and installing mathvec @<:@default depends on architecture@:>@])],
466 [build_mathvec=$enableval],
467 [build_mathvec=notset])
471 # error no CET compiler support
473 [libc_cv_compiler_default_cet=yes],
474 [libc_cv_compiler_default_cet=no])
477 AC_HELP_STRING([--enable-cet],
478 [enable Intel Control-flow Enforcement Technology (CET), x86 only]),
479 [enable_cet=$enableval],
480 [enable_cet=$libc_cv_compiler_default_cet])
482 # We keep the original values in `$config_*' and never modify them, so we
483 # can write them unchanged into config.make. Everything else uses
484 # $machine, $vendor, and $os, and changes them whenever convenient.
485 config_machine=$host_cpu config_vendor=$host_vendor config_os=$host_os
487 # Don't allow vendor == "unknown"
488 test "$config_vendor" = unknown && config_vendor=
489 config_os="`echo $config_os | sed 's/^unknown-//'`"
491 # Some configurations imply other options.
494 # The configure fragment of a port can modify these to supplement
495 # or override the table in the case statement below. No fragment should
496 # ever change the config_* variables, however.
497 machine=$config_machine
498 vendor=$config_vendor
504 AS_HELP_STRING([--with-cpu=CPU], [select code for CPU variant]),
507 yes|'') AC_MSG_ERROR([--with-cpu requires an argument]) ;;
509 *) submachine="$withval" ;;
513 # An preconfigure script can set this when it wants to disable the sanity
517 # A preconfigure script for a system that may or may not use fpu
518 # sysdeps directories sets this to a preprocessor conditional for
519 # whether to use such directories.
522 dnl Let sysdeps/*/preconfigure act here.
523 LIBC_PRECONFIGURE([$srcdir], [for sysdeps])
527 ### By using the undocumented --enable-hacker-mode option for configure
528 ### one can skip this test to make the configuration not fail for unsupported
531 if test -z "$enable_hacker_mode" && test x"$libc_config_ok" != xyes; then
532 case "$machine-$host_os" in
537 *** The GNU C library is currently unavailable for this platform.
538 *** If you are interested in seeing glibc on this platform visit
539 *** the "How to submit a new port" in the wiki:
540 *** https://sourceware.org/glibc/wiki/#Development
541 *** and join the community!])
546 # Set base_machine if not set by a preconfigure fragment.
547 test -n "$base_machine" || base_machine=$machine
548 AC_SUBST(base_machine)
550 # Determine whether to use fpu or nofpu sysdeps directories.
551 AC_CACHE_CHECK([for use of fpu sysdeps directories],
552 libc_cv_with_fp, [dnl
553 cat > conftest.c <<EOF
557 # error "no hardware floating point"
561 if ${CC-cc} $CFLAGS $CPPFLAGS -S conftest.c -o conftest.s \
562 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
566 AC_SUBST(libc_cv_with_fp)
568 AC_CACHE_CHECK(for -fstack-protector, libc_cv_ssp, [dnl
569 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector],
574 AC_CACHE_CHECK(for -fstack-protector-strong, libc_cv_ssp_strong, [dnl
575 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-strong],
576 [libc_cv_ssp_strong=yes],
577 [libc_cv_ssp_strong=no])
580 AC_CACHE_CHECK(for -fstack-protector-all, libc_cv_ssp_all, [dnl
581 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-all],
582 [libc_cv_ssp_all=yes],
583 [libc_cv_ssp_all=no])
588 if test "$libc_cv_ssp" = yes; then
589 no_stack_protector="-fno-stack-protector -DSTACK_PROTECTOR_LEVEL=0"
590 AC_DEFINE(HAVE_CC_NO_STACK_PROTECTOR)
593 if test "$enable_stack_protector" = yes && test "$libc_cv_ssp" = yes; then
594 stack_protector="-fstack-protector"
595 AC_DEFINE(STACK_PROTECTOR_LEVEL, 1)
596 elif test "$enable_stack_protector" = all && test "$libc_cv_ssp_all" = yes; then
597 stack_protector="-fstack-protector-all"
598 AC_DEFINE(STACK_PROTECTOR_LEVEL, 2)
599 elif test "$enable_stack_protector" = strong && test "$libc_cv_ssp_strong" = yes; then
600 stack_protector="-fstack-protector-strong"
601 AC_DEFINE(STACK_PROTECTOR_LEVEL, 3)
603 stack_protector="-fno-stack-protector"
604 AC_DEFINE(STACK_PROTECTOR_LEVEL, 0)
606 AC_SUBST(libc_cv_ssp)
607 AC_SUBST(stack_protector)
608 AC_SUBST(no_stack_protector)
610 if test -n "$stack_protector"; then
611 dnl Don't run configure tests with stack-protection on, to avoid problems with
613 no_ssp=-fno-stack-protector
617 if test "$enable_stack_protector" != no; then
618 AC_MSG_ERROR([--enable-stack-protector=$enable_stack_protector specified, but specified level of stack protection is not supported by the compiler.])
622 # For the multi-arch option we need support in the assembler & linker.
623 AC_CACHE_CHECK([for assembler and linker STT_GNU_IFUNC support],
624 libc_cv_ld_gnu_indirect_function, [dnl
625 cat > conftest.S <<EOF
626 .type foo,%gnu_indirect_function
639 libc_cv_ld_gnu_indirect_function=no
640 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
641 -nostartfiles -nostdlib $no_ssp \
642 -o conftest conftest.S 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
643 # Do a link to see if the backend supports IFUNC relocs.
644 $READELF -r conftest 1>&AS_MESSAGE_LOG_FD
645 LC_ALL=C $READELF -Wr conftest | grep -q 'IRELATIVE\|R_SPARC_JMP_IREL' && {
646 libc_cv_ld_gnu_indirect_function=yes
651 # Check if gcc supports attribute ifunc as it is used in libc_ifunc macro.
652 AC_CACHE_CHECK([for gcc attribute ifunc support],
653 libc_cv_gcc_indirect_function, [dnl
654 cat > conftest.c <<EOF
655 extern int func (int);
656 int used_func (int a)
660 static void *resolver ()
664 extern __typeof (func) func __attribute__ ((ifunc ("resolver")));
666 libc_cv_gcc_indirect_function=no
667 if ${CC-cc} -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD \
668 2>&AS_MESSAGE_LOG_FD ; then
669 if $READELF -s conftest.o | grep IFUNC >/dev/null 2>&AS_MESSAGE_LOG_FD; then
670 libc_cv_gcc_indirect_function=yes
675 # Check if linker supports textrel relocation with ifunc (used on elf/tests).
676 # Note that it relies on libc_cv_ld_gnu_indirect_function test above.
677 AC_CACHE_CHECK([whether the linker supports textrels along with ifunc],
678 libc_cv_textrel_ifunc, [dnl
679 cat > conftest.S <<EOF
680 .type foo,%gnu_indirect_function
701 libc_cv_textrel_ifunc=no
702 if test $libc_cv_ld_gnu_indirect_function = yes; then
703 if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp -pie -o conftest conftest.S); then
704 libc_cv_textrel_ifunc=yes
708 AC_SUBST(libc_cv_textrel_ifunc)
710 # Check if gcc warns about alias for function with incompatible types.
711 AC_CACHE_CHECK([if compiler warns about alias for function with incompatible types],
712 libc_cv_gcc_incompatible_alias, [dnl
713 cat > conftest.c <<EOF
714 int __redirect_foo (const void *s, int c);
716 __typeof (__redirect_foo) *foo_impl (void) __asm__ ("foo");
717 __typeof (__redirect_foo) *foo_impl (void)
722 extern __typeof (__redirect_foo) foo_alias __attribute__ ((alias ("foo")));
724 libc_cv_gcc_incompatible_alias=yes
725 if ${CC-cc} -Werror -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
726 libc_cv_gcc_incompatible_alias=no
730 if test x"$libc_cv_ld_gnu_indirect_function" != xyes; then
731 if test x"$multi_arch" = xyes; then
732 AC_MSG_ERROR([--enable-multi-arch support requires assembler and linker support])
737 if test x"$libc_cv_gcc_indirect_function" != xyes; then
738 # GCC 8+ emits a warning for alias with incompatible types and it might
739 # fail to build ifunc resolvers aliases to either weak or internal
740 # symbols. Disables multiarch build in this case.
741 if test x"$libc_cv_gcc_incompatible_alias" == xyes; then
742 AC_MSG_WARN([gcc emits a warning for alias between functions of incompatible types])
743 if test x"$multi_arch" = xyes; then
744 AC_MSG_ERROR([--enable-multi-arch support requires a gcc with gnu-indirect-function support])
746 AC_MSG_WARN([Multi-arch is disabled.])
748 elif test x"$multi_arch" = xyes; then
749 AC_MSG_WARN([--enable-multi-arch support recommends a gcc with gnu-indirect-function support.
750 Please use a gcc which supports it by default or configure gcc with --enable-gnu-indirect-function])
754 if test x"$multi_arch" != xno; then
755 multi_arch_d=/multiarch
758 # Compute the list of sysdep directories for this configuration.
759 # This can take a while to compute.
760 sysdep_dir=$srcdir/sysdeps
761 AC_MSG_CHECKING(sysdep dirs)
762 dnl We need to use [ and ] for other purposes for a while now.
764 # Make sco3.2v4 become sco3.2.4 and sunos4.1.1_U1 become sunos4.1.1.U1.
765 os="`echo $os | sed 's/\([0-9A-Z]\)[v_]\([0-9A-Z]\)/\1.\2/g'`"
767 test "x$base_os" != x || case "$os" in
774 # For sunos4.1.1, try sunos4.1.1, then sunos4.1, then sunos4, then sunos.
777 while o=`echo $tail | sed 's/\.[^.]*$//'`; test $o != $tail; do
781 o=`echo $tail | sed 's/[0-9]*$//'`
782 if test $o != $tail; then
785 # For linux-gnu, try linux-gnu, then linux.
786 o=`echo $tail | sed 's/-.*$//'`
787 if test $o != $tail; then
791 # For unix/sysv/sysv4, try unix/sysv/sysv4, then unix/sysv, then unix.
794 while b=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$b"; do
800 # For sparc/sparc32, try sparc/sparc32 and then sparc.
802 tail=$machine${submachine:+/$submachine}
803 while m=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$m"; do
805 # Prepend the machine's FPU directory unless the architecture specific
806 # preconfigure disables it.
807 if test "$libc_cv_with_fp" = yes; then
812 # For each machine term, try it with and then without /multiarch.
813 for try_fpu in $maybe_fpu ''; do
814 for try_multi in $multi_arch_d ''; do
815 mach="$mach /$1$try_fpu$try_multi"
821 dnl We are done with glob and regexp uses of [ and ]; return to autoconf.
824 # Find what sysdep directories exist.
826 for b in $base ''; do
827 for m0 in $mach ''; do
828 for v in /$vendor ''; do
829 test "$v" = / && continue
830 for o in /$ostry ''; do
831 test "$o" = / && continue
832 for m in $mach ''; do
833 try_suffix="$m0$b$v$o$m"
834 if test -n "$try_suffix"; then
835 try_srcdir="${srcdir}/"
836 try="sysdeps$try_suffix"
837 test -n "$enable_debug_configure" &&
838 echo "$0 [DEBUG]: try $try" >&2
839 if test -d "$try_srcdir$try"; then
840 sysnames="$sysnames $try"
841 { test -n "$o" || test -n "$b"; } && os_used=t
842 { test -n "$m" || test -n "$m0"; } && machine_used=t
844 x*/$submachine) submachine_used=t ;;
854 # If the assembler supports gnu_indirect_function symbol type and the
855 # architecture supports multi-arch, we enable multi-arch by default.
860 test x"$multi_arch" = xdefault && multi_arch=no
863 if test x"$multi_arch" != xno; then
864 AC_DEFINE(USE_MULTIARCH)
868 if test -z "$os_used" && test "$os" != none; then
869 AC_MSG_ERROR(Operating system $os is not supported.)
871 if test -z "$machine_used" && test "$machine" != none; then
872 AC_MSG_ERROR(The $machine is not supported.)
874 if test -z "$submachine_used" && test -n "$submachine"; then
875 AC_MSG_ERROR(The $submachine subspecies of $host_cpu is not supported.)
879 # We have now validated the configuration.
881 # Expand the list of system names into a full list of directories
882 # from each element's parent name and Implies file (if present).
885 while test $# -gt 0; do
889 case " $names " in *" $name "*)
890 # Already in the list.
894 # Report each name as we discover it, so there is no long pause in output.
895 echo $ECHO_N "$name $ECHO_C" >&AS_MESSAGE_FD
897 name_base=`echo $name | sed -e 's@\(.*sysdeps\)/.*@\1@'`
901 *) xsrcdir=$srcdir/ ;;
903 test -n "$enable_debug_configure" &&
904 echo "[DEBUG]: name/Implies $xsrcdir$name/Implies" >&2
906 for implies_file in Implies Implies-before Implies-after; do
907 implies_type=`echo $implies_file | sed s/-/_/`
908 eval ${implies_type}=
909 if test -f $xsrcdir$name/$implies_file; then
910 # Collect more names from the `Implies' file (removing comments).
911 implied_candidate="`sed 's/#.*$//' < $xsrcdir$name/$implies_file`"
912 for x in $implied_candidate; do
914 if test -d $xsrcdir$name_base/$x; then
915 eval "${implies_type}=\"\$${implies_type} \$name_base/\$x\""
920 test -n "$enable_debug_configure" &&
921 echo "[DEBUG]: $name $implies_file $x try() {$try_srcdir}$try" >&2
922 if test $try != $xsrcdir$name_base/$x && test -d $try_srcdir$try;
924 eval "${implies_type}=\"\$${implies_type} \$try\""
927 if test $found = no; then
928 AC_MSG_WARN($name/$implies_file specifies nonexistent $x)
934 # Add NAME to the list of names.
937 # Find the parent of NAME, using the empty string if it has none.
939 parent="`echo $name | sed -n -e 's=/[^/]*$==' -e '/sysdeps$/q' -e p`"
942 test -n "$enable_debug_configure" &&
943 echo "[DEBUG]: $name Implies='$Implies' rest='$*' parent='$parent' \
944 Implies_before='$Implies_before' Implies_after='$Implies_after'" >&2
946 # Add the names implied by NAME, and NAME's parent (if it has one), to
947 # the list of names to be processed (the argument list). We prepend the
948 # implied names to the list and append the parent. We want implied
949 # directories to come before further directories inferred from the
950 # configuration components; this ensures that for sysv4, unix/common
951 # (implied by unix/sysv/sysv4) comes before unix/sysv (in ostry (here $*)
953 sysnames="`echo $Implies $* $Implies_before $parent $Implies_after`"
954 test -n "$sysnames" && set $sysnames
957 # Add the default directories.
958 default_sysnames="sysdeps/generic"
959 sysnames="$names $default_sysnames"
961 # The other names were emitted during the scan.
962 AC_MSG_RESULT($default_sysnames)
968 if test "$INSTALL" = "${srcdir}/scripts/install-sh -c"; then
969 # The makefiles need to use a different form to find it in $srcdir.
970 INSTALL='\$(..)./scripts/install-sh -c'
976 # Accept binutils 2.25 or newer.
977 AC_CHECK_PROG_VER(AS, $AS, --version,
978 [GNU assembler.* \([0-9]*\.[0-9.]*\)],
979 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
980 AS=: critic_missing="$critic_missing as")
982 if test -n "`$LD --version | sed -n 's/^GNU \(gold\).*$/\1/p'`"; then
983 # Accept gold 1.14 or higher
984 AC_CHECK_PROG_VER(LD, $LD, --version,
985 [GNU gold.* \([0-9][0-9]*\.[0-9.]*\)],
986 [1.1[4-9]*|1.[2-9][0-9]*|1.1[0-9][0-9]*|[2-9].*|[1-9][0-9]*],
987 LD=: critic_missing="$critic_missing GNU gold")
989 AC_CHECK_PROG_VER(LD, $LD, --version,
990 [GNU ld.* \([0-9][0-9]*\.[0-9.]*\)],
991 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
992 LD=: critic_missing="$critic_missing GNU ld")
995 # These programs are version sensitive.
997 AC_CHECK_PROG_VER(MAKE, gnumake gmake make, --version,
998 [GNU Make[^0-9]*\([0-9][0-9.]*\)],
999 [[4-9].* | [1-9][0-9]*], critic_missing="$critic_missing make")
1001 AC_CHECK_PROG_VER(MSGFMT, gnumsgfmt gmsgfmt msgfmt, --version,
1002 [GNU gettext.* \([0-9]*\.[0-9.]*\)],
1003 [0.10.3[6-9]* | 0.10.[4-9][0-9]* | 0.1[1-9]* | 0.[2-9][0-9]* | [1-9].*],
1004 MSGFMT=: aux_missing="$aux_missing msgfmt")
1005 AC_CHECK_PROG_VER(MAKEINFO, makeinfo, --version,
1006 [GNU texinfo.* \([0-9][0-9.]*\)],
1007 [4.[7-9]*|4.[1-9][0-9]*|[5-9].*],
1008 MAKEINFO=: aux_missing="$aux_missing makeinfo")
1009 AC_CHECK_PROG_VER(SED, sed, --version,
1010 [GNU sed[^0-9]* \([0-9]*\.[0-9.]*\)],
1011 [3.0[2-9]*|3.[1-9]*|[4-9]*],
1012 SED=: aux_missing="$aux_missing sed")
1013 AC_CHECK_PROG_VER(AWK, gawk, --version,
1014 [GNU Awk[^0-9]*\([0-9][0-9.]*\)],
1015 [3.1.[2-9]*|3.[2-9]*|[4-9]*], critic_missing="$critic_missing gawk")
1016 AC_CHECK_PROG_VER(BISON, bison, --version,
1017 [bison (GNU Bison) \([0-9]*\.[0-9.]*\)],
1018 [2.7*|[3-9].*|[1-9][0-9]*], critic_missing="$critic_missing bison")
1020 AC_CACHE_CHECK([if $CC is sufficient to build libc], libc_cv_compiler_ok, [
1021 AC_TRY_COMPILE([], [
1022 #if !defined __GNUC__ || __GNUC__ < 6 || (__GNUC__ == 6 && __GNUC_MINOR__ < 2)
1023 #error insufficient compiler
1025 [libc_cv_compiler_ok=yes],
1026 [libc_cv_compiler_ok=no])])
1027 AS_IF([test $libc_cv_compiler_ok != yes],
1028 [critic_missing="$critic_missing compiler"])
1030 AC_CHECK_TOOL(NM, nm, false)
1032 if test "x$maintainer" = "xyes"; then
1033 AC_CHECK_PROGS(AUTOCONF, autoconf, no)
1034 case "x$AUTOCONF" in
1035 xno|x|x:) AUTOCONF=no ;;
1038 whether $AUTOCONF${ACFLAGS:+ }$ACFLAGS works, libc_cv_autoconf_works, [dnl
1039 if (cd $srcdir; $AUTOCONF $ACFLAGS configure.ac > /dev/null 2>&1); then
1040 libc_cv_autoconf_works=yes
1042 libc_cv_autoconf_works=no
1044 test $libc_cv_autoconf_works = yes || AUTOCONF=no
1047 if test "x$AUTOCONF" = xno; then
1048 aux_missing="$aux_missing autoconf"
1054 # Check for python3 if available, or else python.
1055 AC_CHECK_PROG_VER(PYTHON_PROG, python3 python, --version,
1056 [Python \([0-9][0-9.]*\)],
1057 [3.[4-9]*|3.[1-9][0-9]*|[4-9].*|[1-9][0-9]*],
1058 critic_missing="$critic_missing python")
1059 PYTHON="$PYTHON_PROG -B"
1062 test -n "$critic_missing" && AC_MSG_ERROR([
1063 *** These critical programs are missing or too old:$critic_missing
1064 *** Check the INSTALL file for required versions.])
1066 test -n "$aux_missing" && AC_MSG_WARN([
1067 *** These auxiliary programs are missing or incompatible versions:$aux_missing
1068 *** some features or tests will be disabled.
1069 *** Check the INSTALL file for required versions.])
1071 # if using special system headers, find out the compiler's sekrit
1072 # header directory and add that to the list. NOTE: Only does the right
1073 # thing on a system that doesn't need fixincludes. (Not presently a problem.)
1074 if test -n "$sysheaders"; then
1075 SYSINCLUDES=-nostdinc
1076 for d in include include-fixed; do
1077 i=`$CC -print-file-name="$d"` && test "x$i" != x && test "x$i" != "x$d" &&
1078 SYSINCLUDES="$SYSINCLUDES -isystem $i"
1080 SYSINCLUDES="$SYSINCLUDES \
1081 -isystem `echo $sysheaders | sed 's/:/ -isystem /g'`"
1082 if test -n "$CXX"; then
1084 for cxxheaders in `$CXX -v -S -x c++ /dev/null -o /dev/null 2>&1 \
1085 | sed -n -e '1,/#include/d' -e 's/^ \(\/.*\/[cg]++\)/\1/p'`; do
1086 test "x$cxxheaders" != x &&
1087 CXX_SYSINCLUDES="$CXX_SYSINCLUDES -isystem $cxxheaders"
1091 AC_SUBST(SYSINCLUDES)
1092 AC_SUBST(CXX_SYSINCLUDES)
1094 # Obtain some C++ header file paths. This is used to make a local
1095 # copy of those headers in Makerules.
1096 if test -n "$CXX"; then
1097 find_cxx_header () {
1098 echo "#include <$1>" | $CXX -M -MP -x c++ - 2>/dev/null \
1099 | sed -n "\,$1:,{s/:\$//;p}"
1101 CXX_CSTDLIB_HEADER="$(find_cxx_header cstdlib)"
1102 CXX_CMATH_HEADER="$(find_cxx_header cmath)"
1103 CXX_BITS_STD_ABS_H="$(find_cxx_header bits/std_abs.h)"
1105 AC_SUBST(CXX_CSTDLIB_HEADER)
1106 AC_SUBST(CXX_CMATH_HEADER)
1107 AC_SUBST(CXX_BITS_STD_ABS_H)
1109 # Test if LD_LIBRARY_PATH contains the notation for the current directory
1110 # since this would lead to problems installing/building glibc.
1111 # LD_LIBRARY_PATH contains the current directory if one of the following
1113 # - one of the terminals (":" and ";") is the first or last sign
1114 # - two terminals occur directly after each other
1115 # - the path contains an element with a dot in it
1116 AC_MSG_CHECKING(LD_LIBRARY_PATH variable)
1118 case ${LD_LIBRARY_PATH} in
1119 [:\;]* | *[:\;] | *[:\;][:\;]* | *[:\;]. | .[:\;]*| . | *[:\;].[:\;]* )
1120 ld_library_path_setting="contains current directory"
1123 ld_library_path_setting="ok"
1127 AC_MSG_RESULT($ld_library_path_setting)
1128 if test "$ld_library_path_setting" != "ok"; then
1130 *** LD_LIBRARY_PATH shouldn't contain the current directory when
1131 *** building glibc. Please change the environment variable
1132 *** and run configure again.])
1135 AC_PATH_PROG(BASH_SHELL, bash, no)
1137 AC_PATH_PROG(PERL, perl, no)
1138 if test "$PERL" != no &&
1139 (eval `$PERL -V:apiversion`; test `expr "$apiversion" \< 5` -ne 0); then
1142 AC_PATH_PROG(INSTALL_INFO, install-info, no,
1143 $PATH:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin)
1145 AC_CACHE_CHECK(for .set assembler directive, libc_cv_asm_set_directive, [dnl
1146 cat > conftest.s <<EOF
1149 .set glibc_conftest_frobozz,foo
1150 .globl glibc_conftest_frobozz
1152 # The alpha-dec-osf1 assembler gives only a warning for `.set'
1153 # (but it doesn't work), so we must do a linking check to be sure.
1154 cat > conftest1.c <<\EOF
1155 extern int glibc_conftest_frobozz;
1156 void _start() { glibc_conftest_frobozz = 1; }
1158 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
1159 -nostartfiles -nostdlib $no_ssp \
1160 -o conftest conftest.s conftest1.c 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
1161 libc_cv_asm_set_directive=yes
1163 libc_cv_asm_set_directive=no
1166 if test $libc_cv_asm_set_directive = yes; then
1167 AC_DEFINE(HAVE_ASM_SET_DIRECTIVE)
1170 AC_CACHE_CHECK(linker support for protected data symbol,
1171 libc_cv_protected_data,
1172 [cat > conftest.c <<EOF
1173 int bar __attribute__ ((visibility ("protected"))) = 1;
1175 libc_cv_protected_data=no
1176 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -o conftest.so); then
1177 cat > conftest.c <<EOF
1179 int main (void) { return bar; }
1181 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp conftest.c -o conftest conftest.so); then
1182 libc_cv_protected_data=yes
1187 AC_SUBST(libc_cv_protected_data)
1189 AC_CACHE_CHECK(linker support for INSERT in linker script,
1191 [cat > conftest.c <<EOF
1192 const int __attribute__ ((section(".bar"))) bar = 0x12345678;
1193 int test (void) { return bar; }
1195 cat > conftest.t <<EOF
1200 INSERT AFTER .rela.dyn;
1203 if AC_TRY_COMMAND([${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -Wl,-T,conftest.t -o conftest.so]); then
1208 AC_SUBST(libc_cv_insert)
1210 AC_CACHE_CHECK(for broken __attribute__((alias())),
1211 libc_cv_broken_alias_attribute,
1212 [cat > conftest.c <<EOF
1213 extern int foo (int x) __asm ("xyzzy");
1214 int bar (int x) { return x; }
1215 extern __typeof (bar) foo __attribute ((weak, alias ("bar")));
1217 extern __typeof (dfoo) dfoo __asm ("abccb");
1220 libc_cv_broken_alias_attribute=yes
1221 if AC_TRY_COMMAND(${CC-cc} -Werror -S conftest.c -o conftest.s 1>&AS_MESSAGE_LOG_FD); then
1222 if grep 'xyzzy' conftest.s >/dev/null &&
1223 grep 'abccb' conftest.s >/dev/null; then
1224 libc_cv_broken_alias_attribute=no
1227 rm -f conftest.c conftest.s
1229 if test $libc_cv_broken_alias_attribute = yes; then
1230 AC_MSG_ERROR(working alias attribute support required)
1233 AC_CACHE_CHECK(whether to put _rtld_local into .sdata section,
1234 libc_cv_have_sdata_section,
1235 [echo "int i;" > conftest.c
1236 libc_cv_have_sdata_section=no
1237 if ${CC-cc} $LDFLAGS -fPIC -shared -Wl,--verbose conftest.c -o conftest.so 2>&1 \
1238 | grep '\.sdata' >/dev/null; then
1239 libc_cv_have_sdata_section=yes
1241 rm -f conftest.c conftest.so
1243 if test $libc_cv_have_sdata_section = yes; then
1244 AC_DEFINE(HAVE_SDATA_SECTION)
1247 AC_CACHE_CHECK(for libunwind-support in compiler,
1248 libc_cv_cc_with_libunwind, [
1249 cat > conftest.c <<EOF
1250 int main (void) { return 0; }
1252 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -static -o conftest \
1253 conftest.c -v 2>&1 >/dev/null | grep ' -lunwind ' >/dev/null; then
1254 libc_cv_cc_with_libunwind=yes
1256 libc_cv_cc_with_libunwind=no
1259 AC_SUBST(libc_cv_cc_with_libunwind)
1260 if test $libc_cv_cc_with_libunwind = yes; then
1261 AC_DEFINE(HAVE_CC_WITH_LIBUNWIND)
1265 AC_CACHE_CHECK(whether --noexecstack is desirable for .S files,
1266 libc_cv_as_noexecstack, [dnl
1267 cat > conftest.c <<EOF
1270 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS
1271 -S -o conftest.s conftest.c 1>&AS_MESSAGE_LOG_FD]) \
1272 && grep .note.GNU-stack conftest.s >/dev/null \
1273 && AC_TRY_COMMAND([${CC-cc} $ASFLAGS -Wa,--noexecstack
1274 -c -o conftest.o conftest.s 1>&AS_MESSAGE_LOG_FD])
1276 libc_cv_as_noexecstack=yes
1278 libc_cv_as_noexecstack=no
1281 if test $libc_cv_as_noexecstack = yes; then
1282 ASFLAGS_config="$ASFLAGS_config -Wa,--noexecstack"
1284 AC_SUBST(ASFLAGS_config)
1286 AC_CACHE_CHECK(for -z combreloc,
1287 libc_cv_z_combreloc, [dnl
1288 cat > conftest.c <<EOF
1289 extern int bar (int);
1291 int foo (void) { return bar (mumble); }
1293 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1294 -fPIC -shared $no_ssp -o conftest.so conftest.c
1295 -nostdlib -nostartfiles
1296 -Wl,-z,combreloc 1>&AS_MESSAGE_LOG_FD])
1298 dnl The following test is a bit weak. We must use a tool which can test
1299 dnl cross-platform since the gcc used can be a cross compiler. Without
1300 dnl introducing new options this is not easily doable. Instead use a tool
1301 dnl which always is cross-platform: readelf. To detect whether -z combreloc
1302 dnl look for a section named .rel.dyn or .rela.dyn.
1303 if $READELF -S conftest.so | grep -E '.rela?.dyn' > /dev/null; then
1304 libc_cv_z_combreloc=yes
1306 libc_cv_z_combreloc=no
1309 libc_cv_z_combreloc=no
1312 if test "$libc_cv_z_combreloc" = yes; then
1313 AC_DEFINE(HAVE_Z_COMBRELOC)
1315 AC_SUBST(libc_cv_z_combreloc)
1317 LIBC_LINKER_FEATURE([-z execstack], [-Wl,-z,execstack],
1318 [libc_cv_z_execstack=yes], [libc_cv_z_execstack=no])
1319 AC_SUBST(libc_cv_z_execstack)
1321 LIBC_LINKER_FEATURE([--no-dynamic-linker],
1322 [-Wl,--no-dynamic-linker],
1323 [libc_cv_no_dynamic_linker=yes],
1324 [libc_cv_no_dynamic_linker=no])
1325 LIBC_CONFIG_VAR([have-no-dynamic-linker], [$libc_cv_no_dynamic_linker])
1327 AC_CACHE_CHECK(for -static-pie, libc_cv_static_pie, [dnl
1328 LIBC_TRY_CC_OPTION([-static-pie],
1329 [libc_cv_static_pie=yes],
1330 [libc_cv_static_pie=no])
1332 LIBC_CONFIG_VAR([have-static-pie], [$libc_cv_static_pie])
1334 AC_CACHE_CHECK(for -fpie, libc_cv_fpie, [dnl
1335 LIBC_TRY_CC_OPTION([-fpie], [libc_cv_fpie=yes], [libc_cv_fpie=no])
1338 AC_SUBST(libc_cv_fpie)
1340 AC_CACHE_CHECK(for --hash-style option,
1341 libc_cv_hashstyle, [dnl
1342 cat > conftest.c <<EOF
1343 int _start (void) { return 42; }
1345 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp
1346 -fPIC -shared -o conftest.so conftest.c
1347 -Wl,--hash-style=both -nostdlib 1>&AS_MESSAGE_LOG_FD])
1349 libc_cv_hashstyle=yes
1351 libc_cv_hashstyle=no
1354 AC_SUBST(libc_cv_hashstyle)
1356 # The linker's default -shared behavior is good enough if it
1357 # does these things that our custom linker scripts ensure that
1358 # all allocated NOTE sections come first.
1359 if test "$use_default_link" = default; then
1360 AC_CACHE_CHECK([for sufficient default -shared layout],
1361 libc_cv_use_default_link, [dnl
1362 libc_cv_use_default_link=no
1363 cat > conftest.s <<\EOF
1364 .section .note.a,"a",%note
1369 .section .note.b,"a",%note
1375 if AC_TRY_COMMAND([dnl
1376 ${CC-cc} $ASFLAGS -shared -o conftest.so conftest.s 1>&AS_MESSAGE_LOG_FD]) &&
1377 ac_try=`$READELF -S conftest.so | sed -n \
1379 s/^ *\[ *[1-9][0-9]*\] *\([^ ][^ ]*\) *\([^ ][^ ]*\) .*$/\2 \1/
1385 libc_seen_a=no libc_seen_b=no
1387 while test $# -ge 2 -a "$1" = NOTE; do
1389 .note.a) libc_seen_a=yes ;;
1390 .note.b) libc_seen_b=yes ;;
1394 case "$libc_seen_a$libc_seen_b" in
1396 libc_cv_use_default_link=yes
1399 echo >&AS_MESSAGE_LOG_FD "\
1400 $libc_seen_a$libc_seen_b from:
1406 use_default_link=$libc_cv_use_default_link
1409 AC_CACHE_CHECK(for GLOB_DAT reloc,
1410 libc_cv_has_glob_dat, [dnl
1411 cat > conftest.c <<EOF
1413 int foo (void) { return mumble; }
1415 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1416 -fPIC -shared -o conftest.so conftest.c
1417 -nostdlib -nostartfiles $no_ssp
1418 1>&AS_MESSAGE_LOG_FD])
1420 dnl look for GLOB_DAT relocation.
1421 if $READELF -rW conftest.so | grep '_GLOB_DAT' > /dev/null; then
1422 libc_cv_has_glob_dat=yes
1424 libc_cv_has_glob_dat=no
1427 libc_cv_has_glob_dat=no
1430 AC_SUBST(libc_cv_has_glob_dat)
1432 AC_CACHE_CHECK(linker output format, libc_cv_output_format, [dnl
1433 if libc_cv_output_format=`
1434 ${CC-cc} -nostartfiles -nostdlib $no_ssp -Wl,--print-output-format 2>&AS_MESSAGE_LOG_FD`
1438 libc_cv_output_format=
1440 test -n "$libc_cv_output_format" || libc_cv_output_format=unknown])
1441 AC_SUBST(libc_cv_output_format)
1443 AC_CACHE_CHECK(for -fno-toplevel-reorder -fno-section-anchors, libc_cv_fno_toplevel_reorder, [dnl
1444 cat > conftest.c <<EOF
1447 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fno-toplevel-reorder -fno-section-anchors
1448 conftest.c 1>&AS_MESSAGE_LOG_FD])
1450 libc_cv_fno_toplevel_reorder=yes
1452 libc_cv_fno_toplevel_reorder=no
1455 if test $libc_cv_fno_toplevel_reorder = yes; then
1456 fno_unit_at_a_time="-fno-toplevel-reorder -fno-section-anchors"
1458 fno_unit_at_a_time=-fno-unit-at-a-time
1460 AC_SUBST(fno_unit_at_a_time)
1462 AC_CACHE_CHECK([for -mtls-dialect=gnu2], libc_cv_mtls_dialect_gnu2,
1464 cat > conftest.c <<EOF
1471 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fPIC -mtls-dialect=gnu2
1472 conftest.c 1>&AS_MESSAGE_LOG_FD])
1474 libc_cv_mtls_dialect_gnu2=yes
1476 libc_cv_mtls_dialect_gnu2=no
1479 AC_SUBST(libc_cv_mtls_dialect_gnu2)
1480 LIBC_CONFIG_VAR([have-mtls-dialect-gnu2], [$libc_cv_mtls_dialect_gnu2])
1482 AC_CACHE_CHECK(whether cc puts quotes around section names,
1483 libc_cv_have_section_quotes,
1484 [cat > conftest.c <<EOF
1485 static const int foo
1486 __attribute__ ((section ("bar"))) = 1;
1488 if ${CC-cc} -S conftest.c -o conftest.s; then
1489 if grep '\.section.*"bar"' conftest.s >/dev/null; then
1490 libc_cv_have_section_quotes=yes
1492 libc_cv_have_section_quotes=no
1495 libc_cv_have_section_quotes=unknown
1497 rm -f conftest.{c,s}
1499 if test $libc_cv_have_section_quotes = yes; then
1500 AC_DEFINE(HAVE_SECTION_QUOTES)
1503 AC_CACHE_CHECK(for __builtin_memset, libc_cv_gcc_builtin_memset, [dnl
1504 cat > conftest.c <<\EOF
1507 __builtin_memset (x, 0, 1000);
1511 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "memset" > /dev/null]);
1513 libc_cv_gcc_builtin_memset=no
1515 libc_cv_gcc_builtin_memset=yes
1518 if test "$libc_cv_gcc_builtin_memset" = yes ; then
1519 AC_DEFINE(HAVE_BUILTIN_MEMSET)
1522 AC_CACHE_CHECK(for redirection of built-in functions, libc_cv_gcc_builtin_redirection, [dnl
1523 cat > conftest.c <<\EOF
1524 extern char *strstr (const char *, const char *) __asm ("my_strstr");
1525 char *foo (const char *a, const char *b)
1527 return __builtin_strstr (a, b);
1531 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "my_strstr" > /dev/null]);
1533 libc_cv_gcc_builtin_redirection=yes
1535 libc_cv_gcc_builtin_redirection=no
1538 if test "$libc_cv_gcc_builtin_redirection" = no; then
1539 AC_MSG_ERROR([support for the symbol redirection needed])
1542 dnl Determine how to disable generation of FMA instructions.
1543 AC_CACHE_CHECK([for compiler option to disable generation of FMA instructions],
1544 libc_cv_cc_nofma, [dnl
1546 for opt in -ffp-contract=off -mno-fused-madd; do
1547 LIBC_TRY_CC_OPTION([$opt], [libc_cv_cc_nofma=$opt; break])
1549 AC_SUBST(libc_cv_cc_nofma)
1551 if test -n "$submachine"; then
1552 AC_CACHE_CHECK([for compiler option for CPU variant],
1553 libc_cv_cc_submachine, [dnl
1554 libc_cv_cc_submachine=no
1555 for opt in "-march=$submachine" "-mcpu=$submachine"; do
1556 LIBC_TRY_CC_OPTION([$opt], [
1557 libc_cv_cc_submachine="$opt"
1560 if test "x$libc_cv_cc_submachine" = xno; then
1561 AC_MSG_ERROR([${CC-cc} does not support $submachine])
1564 AC_SUBST(libc_cv_cc_submachine)
1566 AC_CACHE_CHECK(if $CC accepts -fno-tree-loop-distribute-patterns with \
1567 __attribute__ ((__optimize__)), libc_cv_cc_loop_to_function, [dnl
1568 cat > conftest.c <<EOF
1570 __attribute__ ((__optimize__ ("-fno-tree-loop-distribute-patterns")))
1573 libc_cv_cc_loop_to_function=no
1574 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -c conftest.c])
1576 libc_cv_cc_loop_to_function=yes
1579 if test $libc_cv_cc_loop_to_function = yes; then
1580 AC_DEFINE(HAVE_CC_INHIBIT_LOOP_TO_LIBCALL)
1582 AC_SUBST(libc_cv_cc_loop_to_function)
1584 dnl Check whether we have the gd library available.
1585 AC_MSG_CHECKING(for libgd)
1586 if test "$with_gd" != "no"; then
1587 old_CFLAGS="$CFLAGS"
1588 CFLAGS="$CFLAGS $libgd_include"
1589 old_LDFLAGS="$LDFLAGS"
1590 LDFLAGS="$LDFLAGS $libgd_ldflags"
1592 LIBS="$LIBS -lgd -lpng -lz -lm"
1593 AC_TRY_LINK([#include <gd.h>], [gdImagePng (0, 0)], LIBGD=yes, LIBGD=no)
1594 CFLAGS="$old_CFLAGS"
1595 LDFLAGS="$old_LDFLAGS"
1600 AC_MSG_RESULT($LIBGD)
1604 if test x$with_selinux = xno ; then
1607 # See if we have the SELinux library
1608 AC_CHECK_LIB(selinux, is_selinux_enabled,
1609 have_selinux=yes, have_selinux=no)
1610 if test x$with_selinux = xyes ; then
1611 if test x$have_selinux = xno ; then
1612 AC_MSG_ERROR([SELinux explicitly required, but SELinux library not found])
1616 # Check if we're building with SELinux support.
1617 if test "x$have_selinux" = xyes; then
1618 AC_DEFINE(HAVE_SELINUX, 1, [SELinux support])
1620 # See if we have the libaudit library
1621 AC_CHECK_LIB(audit, audit_log_user_avc_message,
1622 have_libaudit=yes, have_libaudit=no)
1623 if test "x$have_libaudit" = xyes; then
1624 AC_DEFINE(HAVE_LIBAUDIT, 1, [SELinux libaudit support])
1626 AC_SUBST(have_libaudit)
1628 # See if we have the libcap library
1629 AC_CHECK_LIB(cap, cap_init, have_libcap=yes, have_libcap=no)
1630 if test "x$have_libcap" = xyes; then
1631 AC_DEFINE(HAVE_LIBCAP, 1, [SELinux libcap support])
1633 AC_SUBST(have_libcap)
1635 AC_SUBST(have_selinux)
1638 dnl Check for silly hacked compilers predefining _FORTIFY_SOURCE.
1639 dnl Since we are building the implementations of the fortified functions here,
1640 dnl having the macro defined interacts very badly.
1641 AC_CACHE_CHECK([for _FORTIFY_SOURCE predefine], libc_cv_predef_fortify_source,
1642 [AC_TRY_COMPILE([], [
1643 #ifdef _FORTIFY_SOURCE
1646 [libc_cv_predef_fortify_source=no],
1647 [libc_cv_predef_fortify_source=yes])])
1648 if test $libc_cv_predef_fortify_source = yes; then
1649 CPPUNDEFS="${CPPUNDEFS:+$CPPUNDEFS }-U_FORTIFY_SOURCE"
1653 # Some linkers on some architectures support __ehdr_start but with
1654 # bugs. Make sure usage of it does not create relocations in the
1655 # output (as the linker should resolve them all for us).
1656 AC_CACHE_CHECK([whether the linker provides working __ehdr_start],
1657 libc_cv_ehdr_start, [
1658 old_CFLAGS="$CFLAGS"
1659 old_LDFLAGS="$LDFLAGS"
1661 CFLAGS="$CFLAGS -fPIC"
1662 LDFLAGS="$LDFLAGS -nostdlib -nostartfiles -shared $no_ssp"
1664 AC_LINK_IFELSE([AC_LANG_SOURCE([
1669 extern const Ehdr __ehdr_start __attribute__ ((visibility ("hidden")));
1670 long ehdr (void) { return __ehdr_start.val; }
1672 [if $READELF -r conftest | grep -F __ehdr_start >/dev/null; then
1673 libc_cv_ehdr_start=broken
1675 libc_cv_ehdr_start=yes
1676 fi], [libc_cv_ehdr_start=no])
1677 CFLAGS="$old_CFLAGS"
1678 LDFLAGS="$old_LDFLAGS"
1681 if test "$libc_cv_ehdr_start" = yes; then
1682 AC_DEFINE([HAVE_EHDR_START])
1683 elif test "$libc_cv_ehdr_start" = broken; then
1684 AC_MSG_WARN([linker is broken -- you should upgrade])
1687 AC_CACHE_CHECK(for __builtin_trap with no external dependencies,
1688 libc_cv_builtin_trap, [dnl
1689 libc_cv_builtin_trap=no
1690 AC_TRY_COMPILE([], [__builtin_trap ()], [
1691 libc_undefs=`$NM -u conftest.o |
1692 LC_ALL=C $AWK '$1 == "U" { print $2 | "sort -u"; next } { exit(1) }' \
1693 2>&AS_MESSAGE_LOG_FD` || {
1694 AC_MSG_ERROR([confusing output from $NM -u])
1696 echo >&AS_MESSAGE_LOG_FD "libc_undefs='$libc_undefs'"
1697 if test -z "$libc_undefs"; then
1698 libc_cv_builtin_trap=yes
1700 if test $libc_cv_builtin_trap = yes; then
1701 AC_DEFINE([HAVE_BUILTIN_TRAP])
1704 dnl C++ feature tests.
1707 AC_CACHE_CHECK([whether the C++ compiler supports thread_local],
1708 libc_cv_cxx_thread_local, [
1709 old_CXXFLAGS="$CXXFLAGS"
1710 CXXFLAGS="$CXXFLAGS -std=gnu++11"
1711 AC_COMPILE_IFELSE([AC_LANG_SOURCE([
1714 // Compiler support.
1721 S * get () { return &s; }
1723 // libstdc++ support.
1724 #ifndef _GLIBCXX_HAVE___CXA_THREAD_ATEXIT_IMPL
1725 #error __cxa_thread_atexit_impl not supported
1728 [libc_cv_cxx_thread_local=yes],
1729 [libc_cv_cxx_thread_local=no])
1730 CXXFLAGS="$old_CXXFLAGS"
1732 AC_SUBST(libc_cv_cxx_thread_local)
1735 dnl End of C++ feature tests.
1737 ### End of automated tests.
1738 ### Now run sysdeps configure fragments.
1740 # They also can set these variables.
1742 ldd_rewrite_script=no
1743 libc_cv_sysconfdir=$sysconfdir
1744 libc_cv_localstatedir=$localstatedir
1745 libc_cv_gcc_unwind_find_fde=no
1748 # Iterate over all the sysdep directories we will use, running their
1749 # configure fragments.
1750 for dir in $sysnames; do
1753 *) dest=$srcdir/$dir ;;
1755 if test -r $dest/configure; then
1756 AC_MSG_RESULT(running configure fragment for $dir)
1761 if test x"$build_mathvec" = xnotset; then
1764 LIBC_CONFIG_VAR([build-mathvec], [$build_mathvec])
1766 AC_SUBST(libc_extra_cflags)
1767 AC_SUBST(libc_extra_cppflags)
1769 if test x$libc_cv_gcc_unwind_find_fde = xyes; then
1770 AC_DEFINE(EXPORT_UNWIND_FIND_FDE)
1772 AC_SUBST(libc_cv_gcc_unwind_find_fde)
1774 # A sysdeps configure fragment can reset this if IFUNC is not actually
1775 # usable even though the assembler knows how to generate the symbol type.
1776 if test x"$libc_cv_ld_gnu_indirect_function" = xyes; then
1777 AC_DEFINE(HAVE_IFUNC)
1779 LIBC_CONFIG_VAR([have-ifunc], [$libc_cv_ld_gnu_indirect_function])
1781 if test x"$libc_cv_gcc_indirect_function" = xyes; then
1782 AC_DEFINE(HAVE_GCC_IFUNC)
1785 # This is far from the AC_ARG_ENABLE that sets it so that a sysdeps
1786 # configure fragment can override the value to prevent this AC_DEFINE.
1788 if test "x$use_nscd" != xno; then
1789 AC_DEFINE([USE_NSCD])
1791 if test "x$build_nscd" = xdefault; then
1792 build_nscd=$use_nscd
1795 AC_SUBST(libc_cv_slibdir)
1796 AC_SUBST(libc_cv_rtlddir)
1797 AC_SUBST(libc_cv_complocaledir)
1798 AC_SUBST(libc_cv_sysconfdir)
1799 AC_SUBST(libc_cv_localstatedir)
1800 AC_SUBST(libc_cv_rootsbindir)
1802 if test x$use_ldconfig = xyes; then
1803 AC_DEFINE(USE_LDCONFIG)
1805 AC_SUBST(use_ldconfig)
1806 AC_SUBST(ldd_rewrite_script)
1811 AC_CACHE_CHECK([whether -fPIC is default], libc_cv_pic_default,
1812 [libc_cv_pic_default=yes
1813 cat > conftest.c <<EOF
1814 #if defined __PIC__ || defined __pic__ || defined PIC || defined pic
1815 # error PIC is default.
1818 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1819 libc_cv_pic_default=no
1822 AC_SUBST(libc_cv_pic_default)
1824 AC_CACHE_CHECK([whether -fPIE is default], libc_cv_cc_pie_default,
1825 [libc_cv_cc_pie_default=yes
1826 cat > conftest.c <<EOF
1827 #if defined __PIE__ || defined __pie__ || defined PIE || defined pie
1828 # error PIE is default.
1831 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1832 libc_cv_cc_pie_default=no
1835 libc_cv_pie_default=$libc_cv_cc_pie_default
1836 AC_SUBST(libc_cv_cc_pie_default)
1837 AC_SUBST(libc_cv_pie_default)
1839 # Set the `multidir' variable by grabbing the variable from the compiler.
1840 # We do it once and save the result in a generated makefile.
1841 libc_cv_multidir=`${CC-cc} $CFLAGS $CPPFLAGS -print-multi-directory`
1842 AC_SUBST(libc_cv_multidir)
1844 if test "$static_pie" = yes; then
1845 # The linker must support --no-dynamic-linker.
1846 if test "$libc_cv_no_dynamic_linker" != yes; then
1847 AC_MSG_ERROR([linker support for --no-dynamic-linker needed])
1850 libc_cv_pie_default=yes
1851 AC_DEFINE(ENABLE_STATIC_PIE)
1853 LIBC_CONFIG_VAR([enable-static-pie], [$static_pie])
1856 AC_SUBST(static_nss)
1860 dnl See sysdeps/mach/configure.ac for this variable.
1861 AC_SUBST(mach_interface_list)
1863 VERSION=`sed -n -e 's/^#define VERSION "\([^"]*\)"/\1/p' < $srcdir/version.h`
1864 RELEASE=`sed -n -e 's/^#define RELEASE "\([^"]*\)"/\1/p' < $srcdir/version.h`
1868 AC_CONFIG_FILES([config.make Makefile])
1869 AC_CONFIG_COMMANDS([default],[[
1870 case $CONFIG_FILES in *config.make*)
1871 echo "$config_vars" >> config.make;;
1873 test -d bits || mkdir bits]],[[config_vars='$config_vars']])