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([crypt],
315 AC_HELP_STRING([--disable-crypt],
316 [do not build nor install the passphrase hashing library, libcrypt]),
317 [build_crypt=$enableval],
319 AC_SUBST(build_crypt)
321 AC_ARG_ENABLE([nss-crypt],
322 AC_HELP_STRING([--enable-nss-crypt],
323 [enable libcrypt to use nss]),
324 [nss_crypt=$enableval],
326 if test x$build_libcrypt = xno && test x$nss_crypt = xyes; then
327 AC_MSG_WARN([--enable-nss-crypt has no effect when libcrypt is disabled])
330 if test x$nss_crypt = xyes; then
331 nss_includes=-I$(nss-config --includedir 2>/dev/null)
332 if test $? -ne 0; then
333 AC_MSG_ERROR([cannot find include directory with nss-config])
335 nspr_includes=-I$(nspr-config --includedir 2>/dev/null)
336 if test $? -ne 0; then
337 AC_MSG_ERROR([cannot find include directory with nspr-config])
340 CFLAGS="$CFLAGS $nss_includes $nspr_includes"
341 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
343 #include <nsslowhash.h>
344 void f (void) { NSSLOW_Init (); }])],
345 libc_cv_nss_crypt=yes,
347 cannot find NSS headers with lowlevel hash function interfaces]))
349 old_LDFLAGS="$LDFLAGS"
350 LIBS="$LIBS -lfreebl3"
351 AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
353 #include <nsslowhash.h>],
355 libc_cv_nss_crypt=yes,
357 cannot link program using lowlevel NSS hash functions]))
358 # Check to see if there is a static NSS cryptographic library.
359 # If there isn't then we can't link anything with libcrypt.a,
360 # and that might mean disabling some static tests.
361 LDFLAGS="$LDFLAGS -static"
362 AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
364 #include <nsslowhash.h>],
366 libc_cv_static_nss_crypt=yes,
367 libc_cv_static_nss_crypt=no)
368 LDFLAGS="$old_LDFLAGS"
373 libc_cv_static_nss_crypt=no
375 AC_SUBST(libc_cv_nss_crypt)
376 AC_SUBST(libc_cv_static_nss_crypt)
379 AC_ARG_ENABLE([obsolete-rpc],
380 AC_HELP_STRING([--enable-obsolete-rpc],
381 [build and install the obsolete RPC code for link-time usage]),
382 [link_obsolete_rpc=$enableval],
383 [link_obsolete_rpc=no])
384 AC_SUBST(link_obsolete_rpc)
386 if test "$link_obsolete_rpc" = yes; then
387 AC_DEFINE(LINK_OBSOLETE_RPC)
390 AC_ARG_ENABLE([obsolete-nsl],
391 AC_HELP_STRING([--enable-obsolete-nsl],
392 [build and install the obsolete libnsl library and depending NSS modules]),
393 [build_obsolete_nsl=$enableval],
394 [build_obsolete_nsl=no])
395 AC_SUBST(build_obsolete_nsl)
397 if test "$build_obsolete_nsl" = yes; then
398 AC_DEFINE(LINK_OBSOLETE_NSL)
401 AC_ARG_ENABLE([systemtap],
402 [AS_HELP_STRING([--enable-systemtap],
403 [enable systemtap static probe points @<:@default=no@:>@])],
404 [systemtap=$enableval],
406 if test "x$systemtap" != xno; then
407 AC_CACHE_CHECK([for systemtap static probe support], libc_cv_sdt, [dnl
409 CFLAGS="-std=gnu11 $CFLAGS"
410 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <sys/sdt.h>
411 void foo (int i, void *p)
413 asm ("" STAP_PROBE_ASM (foo, bar, STAP_PROBE_ASM_TEMPLATE (2)) ""
414 :: STAP_PROBE_ASM_OPERANDS (2, i, p));
415 }]])], [libc_cv_sdt=yes], [libc_cv_sdt=no])
416 CFLAGS="$old_CFLAGS"])
417 if test $libc_cv_sdt = yes; then
418 AC_DEFINE([USE_STAP_PROBE])
419 elif test "x$systemtap" != xauto; then
420 AC_MSG_FAILURE([systemtap support needs sys/sdt.h with asm support])
424 AC_ARG_ENABLE([build-nscd],
425 [AS_HELP_STRING([--disable-build-nscd],
426 [disable building and installing the nscd daemon])],
427 [build_nscd=$enableval],
428 [build_nscd=default])
431 # Note the use of $use_nscd is near the bottom of the file.
432 AC_ARG_ENABLE([nscd],
433 [AS_HELP_STRING([--disable-nscd],
434 [library functions will not contact the nscd daemon])],
435 [use_nscd=$enableval],
438 AC_ARG_ENABLE([pt_chown],
439 [AS_HELP_STRING([--enable-pt_chown],
440 [Enable building and installing pt_chown])],
441 [build_pt_chown=$enableval],
443 AC_SUBST(build_pt_chown)
444 if test "$build_pt_chown" = yes; then
445 AC_DEFINE(HAVE_PT_CHOWN)
448 AC_ARG_ENABLE([tunables],
449 [AS_HELP_STRING([--enable-tunables],
450 [Enable tunables support. Known values are 'yes', 'no' and 'valstring'])],
451 [have_tunables=$enableval],
453 AC_SUBST(have_tunables)
454 if test "$have_tunables" = yes; then
455 AC_DEFINE(HAVE_TUNABLES)
458 # The abi-tags file uses a fairly simplistic model for name recognition that
459 # can't distinguish i486-pc-linux-gnu fully from i486-pc-gnu. So we mutate a
460 # $host_os of `gnu*' here to be `gnu-gnu*' just so that it can tell.
461 # This doesn't get used much beyond that, so it's fairly safe.
466 host_os=`echo $host_os | sed -e 's/gnu/gnu-gnu/'`
470 AC_ARG_ENABLE([mathvec],
471 [AS_HELP_STRING([--enable-mathvec],
472 [Enable building and installing mathvec @<:@default depends on architecture@:>@])],
473 [build_mathvec=$enableval],
474 [build_mathvec=notset])
478 # error no CET compiler support
480 [libc_cv_compiler_default_cet=yes],
481 [libc_cv_compiler_default_cet=no])
484 AC_HELP_STRING([--enable-cet],
485 [enable Intel Control-flow Enforcement Technology (CET), x86 only]),
486 [enable_cet=$enableval],
487 [enable_cet=$libc_cv_compiler_default_cet])
489 # We keep the original values in `$config_*' and never modify them, so we
490 # can write them unchanged into config.make. Everything else uses
491 # $machine, $vendor, and $os, and changes them whenever convenient.
492 config_machine=$host_cpu config_vendor=$host_vendor config_os=$host_os
494 # Don't allow vendor == "unknown"
495 test "$config_vendor" = unknown && config_vendor=
496 config_os="`echo $config_os | sed 's/^unknown-//'`"
498 # Some configurations imply other options.
501 # The configure fragment of a port can modify these to supplement
502 # or override the table in the case statement below. No fragment should
503 # ever change the config_* variables, however.
504 machine=$config_machine
505 vendor=$config_vendor
511 AS_HELP_STRING([--with-cpu=CPU], [select code for CPU variant]),
514 yes|'') AC_MSG_ERROR([--with-cpu requires an argument]) ;;
516 *) submachine="$withval" ;;
520 # An preconfigure script can set this when it wants to disable the sanity
524 # A preconfigure script for a system that may or may not use fpu
525 # sysdeps directories sets this to a preprocessor conditional for
526 # whether to use such directories.
529 dnl Let sysdeps/*/preconfigure act here.
530 LIBC_PRECONFIGURE([$srcdir], [for sysdeps])
534 ### By using the undocumented --enable-hacker-mode option for configure
535 ### one can skip this test to make the configuration not fail for unsupported
538 if test -z "$enable_hacker_mode" && test x"$libc_config_ok" != xyes; then
539 case "$machine-$host_os" in
544 *** The GNU C library is currently unavailable for this platform.
545 *** If you are interested in seeing glibc on this platform visit
546 *** the "How to submit a new port" in the wiki:
547 *** https://sourceware.org/glibc/wiki/#Development
548 *** and join the community!])
553 # Set base_machine if not set by a preconfigure fragment.
554 test -n "$base_machine" || base_machine=$machine
555 AC_SUBST(base_machine)
557 # Determine whether to use fpu or nofpu sysdeps directories.
558 AC_CACHE_CHECK([for use of fpu sysdeps directories],
559 libc_cv_with_fp, [dnl
560 cat > conftest.c <<EOF
564 # error "no hardware floating point"
568 if ${CC-cc} $CFLAGS $CPPFLAGS -S conftest.c -o conftest.s \
569 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
573 AC_SUBST(libc_cv_with_fp)
575 AC_CACHE_CHECK(for -fstack-protector, libc_cv_ssp, [dnl
576 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector],
581 AC_CACHE_CHECK(for -fstack-protector-strong, libc_cv_ssp_strong, [dnl
582 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-strong],
583 [libc_cv_ssp_strong=yes],
584 [libc_cv_ssp_strong=no])
587 AC_CACHE_CHECK(for -fstack-protector-all, libc_cv_ssp_all, [dnl
588 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-all],
589 [libc_cv_ssp_all=yes],
590 [libc_cv_ssp_all=no])
595 if test "$libc_cv_ssp" = yes; then
596 no_stack_protector="-fno-stack-protector -DSTACK_PROTECTOR_LEVEL=0"
597 AC_DEFINE(HAVE_CC_NO_STACK_PROTECTOR)
600 if test "$enable_stack_protector" = yes && test "$libc_cv_ssp" = yes; then
601 stack_protector="-fstack-protector"
602 AC_DEFINE(STACK_PROTECTOR_LEVEL, 1)
603 elif test "$enable_stack_protector" = all && test "$libc_cv_ssp_all" = yes; then
604 stack_protector="-fstack-protector-all"
605 AC_DEFINE(STACK_PROTECTOR_LEVEL, 2)
606 elif test "$enable_stack_protector" = strong && test "$libc_cv_ssp_strong" = yes; then
607 stack_protector="-fstack-protector-strong"
608 AC_DEFINE(STACK_PROTECTOR_LEVEL, 3)
610 stack_protector="-fno-stack-protector"
611 AC_DEFINE(STACK_PROTECTOR_LEVEL, 0)
613 AC_SUBST(libc_cv_ssp)
614 AC_SUBST(stack_protector)
615 AC_SUBST(no_stack_protector)
617 if test -n "$stack_protector"; then
618 dnl Don't run configure tests with stack-protection on, to avoid problems with
620 no_ssp=-fno-stack-protector
624 if test "$enable_stack_protector" != no; then
625 AC_MSG_ERROR([--enable-stack-protector=$enable_stack_protector specified, but specified level of stack protection is not supported by the compiler.])
629 # For the multi-arch option we need support in the assembler & linker.
630 AC_CACHE_CHECK([for assembler and linker STT_GNU_IFUNC support],
631 libc_cv_ld_gnu_indirect_function, [dnl
632 cat > conftest.S <<EOF
633 .type foo,%gnu_indirect_function
646 libc_cv_ld_gnu_indirect_function=no
647 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
648 -nostartfiles -nostdlib $no_ssp \
649 -o conftest conftest.S 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
650 # Do a link to see if the backend supports IFUNC relocs.
651 $READELF -r conftest 1>&AS_MESSAGE_LOG_FD
652 LC_ALL=C $READELF -Wr conftest | grep -q 'IRELATIVE\|R_SPARC_JMP_IREL' && {
653 libc_cv_ld_gnu_indirect_function=yes
658 # Check if gcc supports attribute ifunc as it is used in libc_ifunc macro.
659 AC_CACHE_CHECK([for gcc attribute ifunc support],
660 libc_cv_gcc_indirect_function, [dnl
661 cat > conftest.c <<EOF
662 extern int func (int);
663 int used_func (int a)
667 static void *resolver ()
671 extern __typeof (func) func __attribute__ ((ifunc ("resolver")));
673 libc_cv_gcc_indirect_function=no
674 if ${CC-cc} -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD \
675 2>&AS_MESSAGE_LOG_FD ; then
676 if $READELF -s conftest.o | grep IFUNC >/dev/null 2>&AS_MESSAGE_LOG_FD; then
677 libc_cv_gcc_indirect_function=yes
682 # Check if linker supports textrel relocation with ifunc (used on elf/tests).
683 # Note that it relies on libc_cv_ld_gnu_indirect_function test above.
684 AC_CACHE_CHECK([whether the linker supports textrels along with ifunc],
685 libc_cv_textrel_ifunc, [dnl
686 cat > conftest.S <<EOF
687 .type foo,%gnu_indirect_function
708 libc_cv_textrel_ifunc=no
709 if test $libc_cv_ld_gnu_indirect_function = yes; then
710 if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp -pie -o conftest conftest.S); then
711 libc_cv_textrel_ifunc=yes
715 AC_SUBST(libc_cv_textrel_ifunc)
717 # Check if gcc warns about alias for function with incompatible types.
718 AC_CACHE_CHECK([if compiler warns about alias for function with incompatible types],
719 libc_cv_gcc_incompatible_alias, [dnl
720 cat > conftest.c <<EOF
721 int __redirect_foo (const void *s, int c);
723 __typeof (__redirect_foo) *foo_impl (void) __asm__ ("foo");
724 __typeof (__redirect_foo) *foo_impl (void)
729 extern __typeof (__redirect_foo) foo_alias __attribute__ ((alias ("foo")));
731 libc_cv_gcc_incompatible_alias=yes
732 if ${CC-cc} -Werror -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
733 libc_cv_gcc_incompatible_alias=no
737 if test x"$libc_cv_ld_gnu_indirect_function" != xyes; then
738 if test x"$multi_arch" = xyes; then
739 AC_MSG_ERROR([--enable-multi-arch support requires assembler and linker support])
744 if test x"$libc_cv_gcc_indirect_function" != xyes; then
745 # GCC 8+ emits a warning for alias with incompatible types and it might
746 # fail to build ifunc resolvers aliases to either weak or internal
747 # symbols. Disables multiarch build in this case.
748 if test x"$libc_cv_gcc_incompatible_alias" == xyes; then
749 AC_MSG_WARN([gcc emits a warning for alias between functions of incompatible types])
750 if test x"$multi_arch" = xyes; then
751 AC_MSG_ERROR([--enable-multi-arch support requires a gcc with gnu-indirect-function support])
753 AC_MSG_WARN([Multi-arch is disabled.])
755 elif test x"$multi_arch" = xyes; then
756 AC_MSG_WARN([--enable-multi-arch support recommends a gcc with gnu-indirect-function support.
757 Please use a gcc which supports it by default or configure gcc with --enable-gnu-indirect-function])
761 if test x"$multi_arch" != xno; then
762 multi_arch_d=/multiarch
765 # Compute the list of sysdep directories for this configuration.
766 # This can take a while to compute.
767 sysdep_dir=$srcdir/sysdeps
768 AC_MSG_CHECKING(sysdep dirs)
769 dnl We need to use [ and ] for other purposes for a while now.
771 # Make sco3.2v4 become sco3.2.4 and sunos4.1.1_U1 become sunos4.1.1.U1.
772 os="`echo $os | sed 's/\([0-9A-Z]\)[v_]\([0-9A-Z]\)/\1.\2/g'`"
774 test "x$base_os" != x || case "$os" in
781 # For sunos4.1.1, try sunos4.1.1, then sunos4.1, then sunos4, then sunos.
784 while o=`echo $tail | sed 's/\.[^.]*$//'`; test $o != $tail; do
788 o=`echo $tail | sed 's/[0-9]*$//'`
789 if test $o != $tail; then
792 # For linux-gnu, try linux-gnu, then linux.
793 o=`echo $tail | sed 's/-.*$//'`
794 if test $o != $tail; then
798 # For unix/sysv/sysv4, try unix/sysv/sysv4, then unix/sysv, then unix.
801 while b=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$b"; do
807 # For sparc/sparc32, try sparc/sparc32 and then sparc.
809 tail=$machine${submachine:+/$submachine}
810 while m=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$m"; do
812 # Prepend the machine's FPU directory unless the architecture specific
813 # preconfigure disables it.
814 if test "$libc_cv_with_fp" = yes; then
819 # For each machine term, try it with and then without /multiarch.
820 for try_fpu in $maybe_fpu ''; do
821 for try_multi in $multi_arch_d ''; do
822 mach="$mach /$1$try_fpu$try_multi"
828 dnl We are done with glob and regexp uses of [ and ]; return to autoconf.
831 # Find what sysdep directories exist.
833 for b in $base ''; do
834 for m0 in $mach ''; do
835 for v in /$vendor ''; do
836 test "$v" = / && continue
837 for o in /$ostry ''; do
838 test "$o" = / && continue
839 for m in $mach ''; do
840 try_suffix="$m0$b$v$o$m"
841 if test -n "$try_suffix"; then
842 try_srcdir="${srcdir}/"
843 try="sysdeps$try_suffix"
844 test -n "$enable_debug_configure" &&
845 echo "$0 [DEBUG]: try $try" >&2
846 if test -d "$try_srcdir$try"; then
847 sysnames="$sysnames $try"
848 { test -n "$o" || test -n "$b"; } && os_used=t
849 { test -n "$m" || test -n "$m0"; } && machine_used=t
851 x*/$submachine) submachine_used=t ;;
861 # If the assembler supports gnu_indirect_function symbol type and the
862 # architecture supports multi-arch, we enable multi-arch by default.
867 test x"$multi_arch" = xdefault && multi_arch=no
870 if test x"$multi_arch" != xno; then
871 AC_DEFINE(USE_MULTIARCH)
875 if test -z "$os_used" && test "$os" != none; then
876 AC_MSG_ERROR(Operating system $os is not supported.)
878 if test -z "$machine_used" && test "$machine" != none; then
879 AC_MSG_ERROR(The $machine is not supported.)
881 if test -z "$submachine_used" && test -n "$submachine"; then
882 AC_MSG_ERROR(The $submachine subspecies of $host_cpu is not supported.)
886 # We have now validated the configuration.
888 # Expand the list of system names into a full list of directories
889 # from each element's parent name and Implies file (if present).
892 while test $# -gt 0; do
896 case " $names " in *" $name "*)
897 # Already in the list.
901 # Report each name as we discover it, so there is no long pause in output.
902 echo $ECHO_N "$name $ECHO_C" >&AS_MESSAGE_FD
904 name_base=`echo $name | sed -e 's@\(.*sysdeps\)/.*@\1@'`
908 *) xsrcdir=$srcdir/ ;;
910 test -n "$enable_debug_configure" &&
911 echo "[DEBUG]: name/Implies $xsrcdir$name/Implies" >&2
913 for implies_file in Implies Implies-before Implies-after; do
914 implies_type=`echo $implies_file | sed s/-/_/`
915 eval ${implies_type}=
916 if test -f $xsrcdir$name/$implies_file; then
917 # Collect more names from the `Implies' file (removing comments).
918 implied_candidate="`sed 's/#.*$//' < $xsrcdir$name/$implies_file`"
919 for x in $implied_candidate; do
921 if test -d $xsrcdir$name_base/$x; then
922 eval "${implies_type}=\"\$${implies_type} \$name_base/\$x\""
927 test -n "$enable_debug_configure" &&
928 echo "[DEBUG]: $name $implies_file $x try() {$try_srcdir}$try" >&2
929 if test $try != $xsrcdir$name_base/$x && test -d $try_srcdir$try;
931 eval "${implies_type}=\"\$${implies_type} \$try\""
934 if test $found = no; then
935 AC_MSG_WARN($name/$implies_file specifies nonexistent $x)
941 # Add NAME to the list of names.
944 # Find the parent of NAME, using the empty string if it has none.
946 parent="`echo $name | sed -n -e 's=/[^/]*$==' -e '/sysdeps$/q' -e p`"
949 test -n "$enable_debug_configure" &&
950 echo "[DEBUG]: $name Implies='$Implies' rest='$*' parent='$parent' \
951 Implies_before='$Implies_before' Implies_after='$Implies_after'" >&2
953 # Add the names implied by NAME, and NAME's parent (if it has one), to
954 # the list of names to be processed (the argument list). We prepend the
955 # implied names to the list and append the parent. We want implied
956 # directories to come before further directories inferred from the
957 # configuration components; this ensures that for sysv4, unix/common
958 # (implied by unix/sysv/sysv4) comes before unix/sysv (in ostry (here $*)
960 sysnames="`echo $Implies $* $Implies_before $parent $Implies_after`"
961 test -n "$sysnames" && set $sysnames
964 # Add the default directories.
965 default_sysnames="sysdeps/generic"
966 sysnames="$names $default_sysnames"
968 # The other names were emitted during the scan.
969 AC_MSG_RESULT($default_sysnames)
975 if test "$INSTALL" = "${srcdir}/scripts/install-sh -c"; then
976 # The makefiles need to use a different form to find it in $srcdir.
977 INSTALL='\$(..)./scripts/install-sh -c'
983 # Accept binutils 2.25 or newer.
984 AC_CHECK_PROG_VER(AS, $AS, --version,
985 [GNU assembler.* \([0-9]*\.[0-9.]*\)],
986 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
987 AS=: critic_missing="$critic_missing as")
989 if test -n "`$LD --version | sed -n 's/^GNU \(gold\).*$/\1/p'`"; then
990 # Accept gold 1.14 or higher
991 AC_CHECK_PROG_VER(LD, $LD, --version,
992 [GNU gold.* \([0-9][0-9]*\.[0-9.]*\)],
993 [1.1[4-9]*|1.[2-9][0-9]*|1.1[0-9][0-9]*|[2-9].*|[1-9][0-9]*],
994 LD=: critic_missing="$critic_missing GNU gold")
996 AC_CHECK_PROG_VER(LD, $LD, --version,
997 [GNU ld.* \([0-9][0-9]*\.[0-9.]*\)],
998 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
999 LD=: critic_missing="$critic_missing GNU ld")
1002 # These programs are version sensitive.
1003 AC_CHECK_TOOL_PREFIX
1004 AC_CHECK_PROG_VER(MAKE, gnumake gmake make, --version,
1005 [GNU Make[^0-9]*\([0-9][0-9.]*\)],
1006 [[4-9].* | [1-9][0-9]*], critic_missing="$critic_missing make")
1008 AC_CHECK_PROG_VER(MSGFMT, gnumsgfmt gmsgfmt msgfmt, --version,
1009 [GNU gettext.* \([0-9]*\.[0-9.]*\)],
1010 [0.10.3[6-9]* | 0.10.[4-9][0-9]* | 0.1[1-9]* | 0.[2-9][0-9]* | [1-9].*],
1011 MSGFMT=: aux_missing="$aux_missing msgfmt")
1012 AC_CHECK_PROG_VER(MAKEINFO, makeinfo, --version,
1013 [GNU texinfo.* \([0-9][0-9.]*\)],
1014 [4.[7-9]*|4.[1-9][0-9]*|[5-9].*],
1015 MAKEINFO=: aux_missing="$aux_missing makeinfo")
1016 AC_CHECK_PROG_VER(SED, sed, --version,
1017 [GNU sed[^0-9]* \([0-9]*\.[0-9.]*\)],
1018 [3.0[2-9]*|3.[1-9]*|[4-9]*],
1019 SED=: aux_missing="$aux_missing sed")
1020 AC_CHECK_PROG_VER(AWK, gawk, --version,
1021 [GNU Awk[^0-9]*\([0-9][0-9.]*\)],
1022 [3.1.[2-9]*|3.[2-9]*|[4-9]*], critic_missing="$critic_missing gawk")
1023 AC_CHECK_PROG_VER(BISON, bison, --version,
1024 [bison (GNU Bison) \([0-9]*\.[0-9.]*\)],
1025 [2.7*|[3-9].*|[1-9][0-9]*], critic_missing="$critic_missing bison")
1027 AC_CACHE_CHECK([if $CC is sufficient to build libc], libc_cv_compiler_ok, [
1028 AC_TRY_COMPILE([], [
1029 #if !defined __GNUC__ || __GNUC__ < 6 || (__GNUC__ == 6 && __GNUC_MINOR__ < 2)
1030 #error insufficient compiler
1032 [libc_cv_compiler_ok=yes],
1033 [libc_cv_compiler_ok=no])])
1034 AS_IF([test $libc_cv_compiler_ok != yes],
1035 [critic_missing="$critic_missing compiler"])
1037 AC_CHECK_TOOL(NM, nm, false)
1039 if test "x$maintainer" = "xyes"; then
1040 AC_CHECK_PROGS(AUTOCONF, autoconf, no)
1041 case "x$AUTOCONF" in
1042 xno|x|x:) AUTOCONF=no ;;
1045 whether $AUTOCONF${ACFLAGS:+ }$ACFLAGS works, libc_cv_autoconf_works, [dnl
1046 if (cd $srcdir; $AUTOCONF $ACFLAGS configure.ac > /dev/null 2>&1); then
1047 libc_cv_autoconf_works=yes
1049 libc_cv_autoconf_works=no
1051 test $libc_cv_autoconf_works = yes || AUTOCONF=no
1054 if test "x$AUTOCONF" = xno; then
1055 aux_missing="$aux_missing autoconf"
1061 # Check for python3 if available, or else python.
1062 AC_CHECK_PROG_VER(PYTHON_PROG, python3 python, --version,
1063 [Python \([0-9][0-9.]*\)],
1064 [3.[4-9]*|3.[1-9][0-9]*|[4-9].*|[1-9][0-9]*],
1065 critic_missing="$critic_missing python")
1066 PYTHON="$PYTHON_PROG -B"
1069 test -n "$critic_missing" && AC_MSG_ERROR([
1070 *** These critical programs are missing or too old:$critic_missing
1071 *** Check the INSTALL file for required versions.])
1073 test -n "$aux_missing" && AC_MSG_WARN([
1074 *** These auxiliary programs are missing or incompatible versions:$aux_missing
1075 *** some features or tests will be disabled.
1076 *** Check the INSTALL file for required versions.])
1078 # if using special system headers, find out the compiler's sekrit
1079 # header directory and add that to the list. NOTE: Only does the right
1080 # thing on a system that doesn't need fixincludes. (Not presently a problem.)
1081 if test -n "$sysheaders"; then
1082 SYSINCLUDES=-nostdinc
1083 for d in include include-fixed; do
1084 i=`$CC -print-file-name="$d"` && test "x$i" != x && test "x$i" != "x$d" &&
1085 SYSINCLUDES="$SYSINCLUDES -isystem $i"
1087 SYSINCLUDES="$SYSINCLUDES \
1088 -isystem `echo $sysheaders | sed 's/:/ -isystem /g'`"
1089 if test -n "$CXX"; then
1091 for cxxheaders in `$CXX -v -S -x c++ /dev/null -o /dev/null 2>&1 \
1092 | sed -n -e '1,/#include/d' -e 's/^ \(\/.*\/[cg]++\)/\1/p'`; do
1093 test "x$cxxheaders" != x &&
1094 CXX_SYSINCLUDES="$CXX_SYSINCLUDES -isystem $cxxheaders"
1098 AC_SUBST(SYSINCLUDES)
1099 AC_SUBST(CXX_SYSINCLUDES)
1101 # Obtain some C++ header file paths. This is used to make a local
1102 # copy of those headers in Makerules.
1103 if test -n "$CXX"; then
1104 find_cxx_header () {
1105 echo "#include <$1>" | $CXX -M -MP -x c++ - 2>/dev/null \
1106 | sed -n "\,$1:,{s/:\$//;p}"
1108 CXX_CSTDLIB_HEADER="$(find_cxx_header cstdlib)"
1109 CXX_CMATH_HEADER="$(find_cxx_header cmath)"
1110 CXX_BITS_STD_ABS_H="$(find_cxx_header bits/std_abs.h)"
1112 AC_SUBST(CXX_CSTDLIB_HEADER)
1113 AC_SUBST(CXX_CMATH_HEADER)
1114 AC_SUBST(CXX_BITS_STD_ABS_H)
1116 # Test if LD_LIBRARY_PATH contains the notation for the current directory
1117 # since this would lead to problems installing/building glibc.
1118 # LD_LIBRARY_PATH contains the current directory if one of the following
1120 # - one of the terminals (":" and ";") is the first or last sign
1121 # - two terminals occur directly after each other
1122 # - the path contains an element with a dot in it
1123 AC_MSG_CHECKING(LD_LIBRARY_PATH variable)
1125 case ${LD_LIBRARY_PATH} in
1126 [:\;]* | *[:\;] | *[:\;][:\;]* | *[:\;]. | .[:\;]*| . | *[:\;].[:\;]* )
1127 ld_library_path_setting="contains current directory"
1130 ld_library_path_setting="ok"
1134 AC_MSG_RESULT($ld_library_path_setting)
1135 if test "$ld_library_path_setting" != "ok"; then
1137 *** LD_LIBRARY_PATH shouldn't contain the current directory when
1138 *** building glibc. Please change the environment variable
1139 *** and run configure again.])
1142 AC_PATH_PROG(BASH_SHELL, bash, no)
1144 AC_PATH_PROG(PERL, perl, no)
1145 if test "$PERL" != no &&
1146 (eval `$PERL -V:apiversion`; test `expr "$apiversion" \< 5` -ne 0); then
1149 AC_PATH_PROG(INSTALL_INFO, install-info, no,
1150 $PATH:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin)
1152 AC_CACHE_CHECK(for .set assembler directive, libc_cv_asm_set_directive, [dnl
1153 cat > conftest.s <<EOF
1156 .set glibc_conftest_frobozz,foo
1157 .globl glibc_conftest_frobozz
1159 # The alpha-dec-osf1 assembler gives only a warning for `.set'
1160 # (but it doesn't work), so we must do a linking check to be sure.
1161 cat > conftest1.c <<\EOF
1162 extern int glibc_conftest_frobozz;
1163 void _start() { glibc_conftest_frobozz = 1; }
1165 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
1166 -nostartfiles -nostdlib $no_ssp \
1167 -o conftest conftest.s conftest1.c 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
1168 libc_cv_asm_set_directive=yes
1170 libc_cv_asm_set_directive=no
1173 if test $libc_cv_asm_set_directive = yes; then
1174 AC_DEFINE(HAVE_ASM_SET_DIRECTIVE)
1177 AC_CACHE_CHECK(linker support for protected data symbol,
1178 libc_cv_protected_data,
1179 [cat > conftest.c <<EOF
1180 int bar __attribute__ ((visibility ("protected"))) = 1;
1182 libc_cv_protected_data=no
1183 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -o conftest.so); then
1184 cat > conftest.c <<EOF
1186 int main (void) { return bar; }
1188 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp conftest.c -o conftest conftest.so); then
1189 libc_cv_protected_data=yes
1194 AC_SUBST(libc_cv_protected_data)
1196 AC_CACHE_CHECK(linker support for INSERT in linker script,
1198 [cat > conftest.c <<EOF
1199 const int __attribute__ ((section(".bar"))) bar = 0x12345678;
1200 int test (void) { return bar; }
1202 cat > conftest.t <<EOF
1207 INSERT AFTER .rela.dyn;
1210 if AC_TRY_COMMAND([${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -Wl,-T,conftest.t -o conftest.so]); then
1215 AC_SUBST(libc_cv_insert)
1217 AC_CACHE_CHECK(for broken __attribute__((alias())),
1218 libc_cv_broken_alias_attribute,
1219 [cat > conftest.c <<EOF
1220 extern int foo (int x) __asm ("xyzzy");
1221 int bar (int x) { return x; }
1222 extern __typeof (bar) foo __attribute ((weak, alias ("bar")));
1224 extern __typeof (dfoo) dfoo __asm ("abccb");
1227 libc_cv_broken_alias_attribute=yes
1228 if AC_TRY_COMMAND(${CC-cc} -Werror -S conftest.c -o conftest.s 1>&AS_MESSAGE_LOG_FD); then
1229 if grep 'xyzzy' conftest.s >/dev/null &&
1230 grep 'abccb' conftest.s >/dev/null; then
1231 libc_cv_broken_alias_attribute=no
1234 rm -f conftest.c conftest.s
1236 if test $libc_cv_broken_alias_attribute = yes; then
1237 AC_MSG_ERROR(working alias attribute support required)
1240 AC_CACHE_CHECK(whether to put _rtld_local into .sdata section,
1241 libc_cv_have_sdata_section,
1242 [echo "int i;" > conftest.c
1243 libc_cv_have_sdata_section=no
1244 if ${CC-cc} $LDFLAGS -fPIC -shared -Wl,--verbose conftest.c -o conftest.so 2>&1 \
1245 | grep '\.sdata' >/dev/null; then
1246 libc_cv_have_sdata_section=yes
1248 rm -f conftest.c conftest.so
1250 if test $libc_cv_have_sdata_section = yes; then
1251 AC_DEFINE(HAVE_SDATA_SECTION)
1254 AC_CACHE_CHECK(whether to use .ctors/.dtors header and trailer,
1255 libc_cv_ctors_header, [dnl
1256 libc_cv_ctors_header=yes
1257 LIBC_TRY_LINK_STATIC([
1258 __attribute__ ((constructor)) void ctor (void) { asm (""); }
1259 __attribute__ ((destructor)) void dtor (void) { asm (""); }
1262 AS_IF([$READELF -WS conftest$ac_exeext | $AWK '
1263 { gsub(/\@<:@ */, "@<:@") }
1264 $2 == ".ctors" || $2 == ".dtors" {
1265 size = strtonum("0x" $6)
1266 align = strtonum("0x" $NF)
1268 stub@<:@$2@:>@ = size == align * 2
1271 ctors_ok = !seen@<:@".ctors"@:>@ || stub@<:@".ctors"@:>@
1272 dtors_ok = !seen@<:@".dtors"@:>@ || stub@<:@".dtors"@:>@
1273 exit ((ctors_ok && dtors_ok) ? 0 : 1)
1275 '], [libc_cv_ctors_header=no])
1277 AC_MSG_ERROR([missing __attribute__ ((constructor)) support??])
1280 if test $libc_cv_ctors_header = no; then
1281 AC_DEFINE(NO_CTORS_DTORS_SECTIONS)
1284 AC_CACHE_CHECK(for libunwind-support in compiler,
1285 libc_cv_cc_with_libunwind, [
1286 cat > conftest.c <<EOF
1287 int main (void) { return 0; }
1289 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -static -o conftest \
1290 conftest.c -v 2>&1 >/dev/null | grep ' -lunwind ' >/dev/null; then
1291 libc_cv_cc_with_libunwind=yes
1293 libc_cv_cc_with_libunwind=no
1296 AC_SUBST(libc_cv_cc_with_libunwind)
1297 if test $libc_cv_cc_with_libunwind = yes; then
1298 AC_DEFINE(HAVE_CC_WITH_LIBUNWIND)
1302 AC_CACHE_CHECK(whether --noexecstack is desirable for .S files,
1303 libc_cv_as_noexecstack, [dnl
1304 cat > conftest.c <<EOF
1307 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS
1308 -S -o conftest.s conftest.c 1>&AS_MESSAGE_LOG_FD]) \
1309 && grep .note.GNU-stack conftest.s >/dev/null \
1310 && AC_TRY_COMMAND([${CC-cc} $ASFLAGS -Wa,--noexecstack
1311 -c -o conftest.o conftest.s 1>&AS_MESSAGE_LOG_FD])
1313 libc_cv_as_noexecstack=yes
1315 libc_cv_as_noexecstack=no
1318 if test $libc_cv_as_noexecstack = yes; then
1319 ASFLAGS_config="$ASFLAGS_config -Wa,--noexecstack"
1321 AC_SUBST(ASFLAGS_config)
1323 AC_CACHE_CHECK(for -z combreloc,
1324 libc_cv_z_combreloc, [dnl
1325 cat > conftest.c <<EOF
1326 extern int bar (int);
1328 int foo (void) { return bar (mumble); }
1330 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1331 -fPIC -shared $no_ssp -o conftest.so conftest.c
1332 -nostdlib -nostartfiles
1333 -Wl,-z,combreloc 1>&AS_MESSAGE_LOG_FD])
1335 dnl The following test is a bit weak. We must use a tool which can test
1336 dnl cross-platform since the gcc used can be a cross compiler. Without
1337 dnl introducing new options this is not easily doable. Instead use a tool
1338 dnl which always is cross-platform: readelf. To detect whether -z combreloc
1339 dnl look for a section named .rel.dyn or .rela.dyn.
1340 if $READELF -S conftest.so | grep -E '.rela?.dyn' > /dev/null; then
1341 libc_cv_z_combreloc=yes
1343 libc_cv_z_combreloc=no
1346 libc_cv_z_combreloc=no
1349 if test "$libc_cv_z_combreloc" = yes; then
1350 AC_DEFINE(HAVE_Z_COMBRELOC)
1352 AC_SUBST(libc_cv_z_combreloc)
1354 LIBC_LINKER_FEATURE([-z execstack], [-Wl,-z,execstack],
1355 [libc_cv_z_execstack=yes], [libc_cv_z_execstack=no])
1356 AC_SUBST(libc_cv_z_execstack)
1358 LIBC_LINKER_FEATURE([--no-dynamic-linker],
1359 [-Wl,--no-dynamic-linker],
1360 [libc_cv_no_dynamic_linker=yes],
1361 [libc_cv_no_dynamic_linker=no])
1362 LIBC_CONFIG_VAR([have-no-dynamic-linker], [$libc_cv_no_dynamic_linker])
1364 AC_CACHE_CHECK(for -static-pie, libc_cv_static_pie, [dnl
1365 LIBC_TRY_CC_OPTION([-static-pie],
1366 [libc_cv_static_pie=yes],
1367 [libc_cv_static_pie=no])
1369 LIBC_CONFIG_VAR([have-static-pie], [$libc_cv_static_pie])
1371 AC_CACHE_CHECK(for -fpie, libc_cv_fpie, [dnl
1372 LIBC_TRY_CC_OPTION([-fpie], [libc_cv_fpie=yes], [libc_cv_fpie=no])
1375 AC_SUBST(libc_cv_fpie)
1377 AC_CACHE_CHECK(for --hash-style option,
1378 libc_cv_hashstyle, [dnl
1379 cat > conftest.c <<EOF
1380 int _start (void) { return 42; }
1382 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp
1383 -fPIC -shared -o conftest.so conftest.c
1384 -Wl,--hash-style=both -nostdlib 1>&AS_MESSAGE_LOG_FD])
1386 libc_cv_hashstyle=yes
1388 libc_cv_hashstyle=no
1391 AC_SUBST(libc_cv_hashstyle)
1393 # The linker's default -shared behavior is good enough if it
1394 # does these things that our custom linker scripts ensure that
1395 # all allocated NOTE sections come first.
1396 if test "$use_default_link" = default; then
1397 AC_CACHE_CHECK([for sufficient default -shared layout],
1398 libc_cv_use_default_link, [dnl
1399 libc_cv_use_default_link=no
1400 cat > conftest.s <<\EOF
1401 .section .note.a,"a",%note
1406 .section .note.b,"a",%note
1412 if AC_TRY_COMMAND([dnl
1413 ${CC-cc} $ASFLAGS -shared -o conftest.so conftest.s 1>&AS_MESSAGE_LOG_FD]) &&
1414 ac_try=`$READELF -S conftest.so | sed -n \
1416 s/^ *\[ *[1-9][0-9]*\] *\([^ ][^ ]*\) *\([^ ][^ ]*\) .*$/\2 \1/
1422 libc_seen_a=no libc_seen_b=no
1424 while test $# -ge 2 -a "$1" = NOTE; do
1426 .note.a) libc_seen_a=yes ;;
1427 .note.b) libc_seen_b=yes ;;
1431 case "$libc_seen_a$libc_seen_b" in
1433 libc_cv_use_default_link=yes
1436 echo >&AS_MESSAGE_LOG_FD "\
1437 $libc_seen_a$libc_seen_b from:
1443 use_default_link=$libc_cv_use_default_link
1446 AC_CACHE_CHECK(for GLOB_DAT reloc,
1447 libc_cv_has_glob_dat, [dnl
1448 cat > conftest.c <<EOF
1450 int foo (void) { return mumble; }
1452 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1453 -fPIC -shared -o conftest.so conftest.c
1454 -nostdlib -nostartfiles $no_ssp
1455 1>&AS_MESSAGE_LOG_FD])
1457 dnl look for GLOB_DAT relocation.
1458 if $READELF -rW conftest.so | grep '_GLOB_DAT' > /dev/null; then
1459 libc_cv_has_glob_dat=yes
1461 libc_cv_has_glob_dat=no
1464 libc_cv_has_glob_dat=no
1467 AC_SUBST(libc_cv_has_glob_dat)
1469 AC_CACHE_CHECK(linker output format, libc_cv_output_format, [dnl
1470 if libc_cv_output_format=`
1471 ${CC-cc} -nostartfiles -nostdlib $no_ssp -Wl,--print-output-format 2>&AS_MESSAGE_LOG_FD`
1475 libc_cv_output_format=
1477 test -n "$libc_cv_output_format" || libc_cv_output_format=unknown])
1478 AC_SUBST(libc_cv_output_format)
1480 AC_CACHE_CHECK(for -fno-toplevel-reorder -fno-section-anchors, libc_cv_fno_toplevel_reorder, [dnl
1481 cat > conftest.c <<EOF
1484 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fno-toplevel-reorder -fno-section-anchors
1485 conftest.c 1>&AS_MESSAGE_LOG_FD])
1487 libc_cv_fno_toplevel_reorder=yes
1489 libc_cv_fno_toplevel_reorder=no
1492 if test $libc_cv_fno_toplevel_reorder = yes; then
1493 fno_unit_at_a_time="-fno-toplevel-reorder -fno-section-anchors"
1495 fno_unit_at_a_time=-fno-unit-at-a-time
1497 AC_SUBST(fno_unit_at_a_time)
1499 AC_CACHE_CHECK([for -mtls-dialect=gnu2], libc_cv_mtls_dialect_gnu2,
1501 cat > conftest.c <<EOF
1508 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fPIC -mtls-dialect=gnu2
1509 conftest.c 1>&AS_MESSAGE_LOG_FD])
1511 libc_cv_mtls_dialect_gnu2=yes
1513 libc_cv_mtls_dialect_gnu2=no
1516 AC_SUBST(libc_cv_mtls_dialect_gnu2)
1517 LIBC_CONFIG_VAR([have-mtls-dialect-gnu2], [$libc_cv_mtls_dialect_gnu2])
1519 AC_CACHE_CHECK(whether cc puts quotes around section names,
1520 libc_cv_have_section_quotes,
1521 [cat > conftest.c <<EOF
1522 static const int foo
1523 __attribute__ ((section ("bar"))) = 1;
1525 if ${CC-cc} -S conftest.c -o conftest.s; then
1526 if grep '\.section.*"bar"' conftest.s >/dev/null; then
1527 libc_cv_have_section_quotes=yes
1529 libc_cv_have_section_quotes=no
1532 libc_cv_have_section_quotes=unknown
1534 rm -f conftest.{c,s}
1536 if test $libc_cv_have_section_quotes = yes; then
1537 AC_DEFINE(HAVE_SECTION_QUOTES)
1540 AC_CACHE_CHECK(for __builtin_memset, libc_cv_gcc_builtin_memset, [dnl
1541 cat > conftest.c <<\EOF
1544 __builtin_memset (x, 0, 1000);
1548 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "memset" > /dev/null]);
1550 libc_cv_gcc_builtin_memset=no
1552 libc_cv_gcc_builtin_memset=yes
1555 if test "$libc_cv_gcc_builtin_memset" = yes ; then
1556 AC_DEFINE(HAVE_BUILTIN_MEMSET)
1559 AC_CACHE_CHECK(for redirection of built-in functions, libc_cv_gcc_builtin_redirection, [dnl
1560 cat > conftest.c <<\EOF
1561 extern char *strstr (const char *, const char *) __asm ("my_strstr");
1562 char *foo (const char *a, const char *b)
1564 return __builtin_strstr (a, b);
1568 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "my_strstr" > /dev/null]);
1570 libc_cv_gcc_builtin_redirection=yes
1572 libc_cv_gcc_builtin_redirection=no
1575 if test "$libc_cv_gcc_builtin_redirection" = no; then
1576 AC_MSG_ERROR([support for the symbol redirection needed])
1579 dnl Determine how to disable generation of FMA instructions.
1580 AC_CACHE_CHECK([for compiler option to disable generation of FMA instructions],
1581 libc_cv_cc_nofma, [dnl
1583 for opt in -ffp-contract=off -mno-fused-madd; do
1584 LIBC_TRY_CC_OPTION([$opt], [libc_cv_cc_nofma=$opt; break])
1586 AC_SUBST(libc_cv_cc_nofma)
1588 if test -n "$submachine"; then
1589 AC_CACHE_CHECK([for compiler option for CPU variant],
1590 libc_cv_cc_submachine, [dnl
1591 libc_cv_cc_submachine=no
1592 for opt in "-march=$submachine" "-mcpu=$submachine"; do
1593 LIBC_TRY_CC_OPTION([$opt], [
1594 libc_cv_cc_submachine="$opt"
1597 if test "x$libc_cv_cc_submachine" = xno; then
1598 AC_MSG_ERROR([${CC-cc} does not support $submachine])
1601 AC_SUBST(libc_cv_cc_submachine)
1603 AC_CACHE_CHECK(if $CC accepts -fno-tree-loop-distribute-patterns with \
1604 __attribute__ ((__optimize__)), libc_cv_cc_loop_to_function, [dnl
1605 cat > conftest.c <<EOF
1607 __attribute__ ((__optimize__ ("-fno-tree-loop-distribute-patterns")))
1610 libc_cv_cc_loop_to_function=no
1611 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -c conftest.c])
1613 libc_cv_cc_loop_to_function=yes
1616 if test $libc_cv_cc_loop_to_function = yes; then
1617 AC_DEFINE(HAVE_CC_INHIBIT_LOOP_TO_LIBCALL)
1619 AC_SUBST(libc_cv_cc_loop_to_function)
1621 dnl Check whether we have the gd library available.
1622 AC_MSG_CHECKING(for libgd)
1623 if test "$with_gd" != "no"; then
1624 old_CFLAGS="$CFLAGS"
1625 CFLAGS="$CFLAGS $libgd_include"
1626 old_LDFLAGS="$LDFLAGS"
1627 LDFLAGS="$LDFLAGS $libgd_ldflags"
1629 LIBS="$LIBS -lgd -lpng -lz -lm"
1630 AC_TRY_LINK([#include <gd.h>], [gdImagePng (0, 0)], LIBGD=yes, LIBGD=no)
1631 CFLAGS="$old_CFLAGS"
1632 LDFLAGS="$old_LDFLAGS"
1637 AC_MSG_RESULT($LIBGD)
1641 if test x$with_selinux = xno ; then
1644 # See if we have the SELinux library
1645 AC_CHECK_LIB(selinux, is_selinux_enabled,
1646 have_selinux=yes, have_selinux=no)
1647 if test x$with_selinux = xyes ; then
1648 if test x$have_selinux = xno ; then
1649 AC_MSG_ERROR([SELinux explicitly required, but SELinux library not found])
1653 # Check if we're building with SELinux support.
1654 if test "x$have_selinux" = xyes; then
1655 AC_DEFINE(HAVE_SELINUX, 1, [SELinux support])
1657 # See if we have the libaudit library
1658 AC_CHECK_LIB(audit, audit_log_user_avc_message,
1659 have_libaudit=yes, have_libaudit=no)
1660 if test "x$have_libaudit" = xyes; then
1661 AC_DEFINE(HAVE_LIBAUDIT, 1, [SELinux libaudit support])
1663 AC_SUBST(have_libaudit)
1665 # See if we have the libcap library
1666 AC_CHECK_LIB(cap, cap_init, have_libcap=yes, have_libcap=no)
1667 if test "x$have_libcap" = xyes; then
1668 AC_DEFINE(HAVE_LIBCAP, 1, [SELinux libcap support])
1670 AC_SUBST(have_libcap)
1672 AC_SUBST(have_selinux)
1675 dnl Check for silly hacked compilers predefining _FORTIFY_SOURCE.
1676 dnl Since we are building the implementations of the fortified functions here,
1677 dnl having the macro defined interacts very badly.
1678 AC_CACHE_CHECK([for _FORTIFY_SOURCE predefine], libc_cv_predef_fortify_source,
1679 [AC_TRY_COMPILE([], [
1680 #ifdef _FORTIFY_SOURCE
1683 [libc_cv_predef_fortify_source=no],
1684 [libc_cv_predef_fortify_source=yes])])
1685 if test $libc_cv_predef_fortify_source = yes; then
1686 CPPUNDEFS="${CPPUNDEFS:+$CPPUNDEFS }-U_FORTIFY_SOURCE"
1690 # Some linkers on some architectures support __ehdr_start but with
1691 # bugs. Make sure usage of it does not create relocations in the
1692 # output (as the linker should resolve them all for us).
1693 AC_CACHE_CHECK([whether the linker provides working __ehdr_start],
1694 libc_cv_ehdr_start, [
1695 old_CFLAGS="$CFLAGS"
1696 old_LDFLAGS="$LDFLAGS"
1698 CFLAGS="$CFLAGS -fPIC"
1699 LDFLAGS="$LDFLAGS -nostdlib -nostartfiles -shared $no_ssp"
1701 AC_LINK_IFELSE([AC_LANG_SOURCE([
1706 extern const Ehdr __ehdr_start __attribute__ ((visibility ("hidden")));
1707 long ehdr (void) { return __ehdr_start.val; }
1709 [if $READELF -r conftest | grep -F __ehdr_start >/dev/null; then
1710 libc_cv_ehdr_start=broken
1712 libc_cv_ehdr_start=yes
1713 fi], [libc_cv_ehdr_start=no])
1714 CFLAGS="$old_CFLAGS"
1715 LDFLAGS="$old_LDFLAGS"
1718 if test "$libc_cv_ehdr_start" = yes; then
1719 AC_DEFINE([HAVE_EHDR_START])
1720 elif test "$libc_cv_ehdr_start" = broken; then
1721 AC_MSG_WARN([linker is broken -- you should upgrade])
1724 AC_CACHE_CHECK(for __builtin_trap with no external dependencies,
1725 libc_cv_builtin_trap, [dnl
1726 libc_cv_builtin_trap=no
1727 AC_TRY_COMPILE([], [__builtin_trap ()], [
1728 libc_undefs=`$NM -u conftest.o |
1729 LC_ALL=C $AWK '$1 == "U" { print $2 | "sort -u"; next } { exit(1) }' \
1730 2>&AS_MESSAGE_LOG_FD` || {
1731 AC_MSG_ERROR([confusing output from $NM -u])
1733 echo >&AS_MESSAGE_LOG_FD "libc_undefs='$libc_undefs'"
1734 if test -z "$libc_undefs"; then
1735 libc_cv_builtin_trap=yes
1737 if test $libc_cv_builtin_trap = yes; then
1738 AC_DEFINE([HAVE_BUILTIN_TRAP])
1741 dnl C++ feature tests.
1744 AC_CACHE_CHECK([whether the C++ compiler supports thread_local],
1745 libc_cv_cxx_thread_local, [
1746 old_CXXFLAGS="$CXXFLAGS"
1747 CXXFLAGS="$CXXFLAGS -std=gnu++11"
1748 AC_COMPILE_IFELSE([AC_LANG_SOURCE([
1751 // Compiler support.
1758 S * get () { return &s; }
1760 // libstdc++ support.
1761 #ifndef _GLIBCXX_HAVE___CXA_THREAD_ATEXIT_IMPL
1762 #error __cxa_thread_atexit_impl not supported
1765 [libc_cv_cxx_thread_local=yes],
1766 [libc_cv_cxx_thread_local=no])
1767 CXXFLAGS="$old_CXXFLAGS"
1769 AC_SUBST(libc_cv_cxx_thread_local)
1772 dnl End of C++ feature tests.
1774 ### End of automated tests.
1775 ### Now run sysdeps configure fragments.
1777 # They also can set these variables.
1779 ldd_rewrite_script=no
1780 libc_cv_sysconfdir=$sysconfdir
1781 libc_cv_localstatedir=$localstatedir
1782 libc_cv_gcc_unwind_find_fde=no
1785 # Iterate over all the sysdep directories we will use, running their
1786 # configure fragments.
1787 for dir in $sysnames; do
1790 *) dest=$srcdir/$dir ;;
1792 if test -r $dest/configure; then
1793 AC_MSG_RESULT(running configure fragment for $dir)
1798 if test x"$build_mathvec" = xnotset; then
1801 LIBC_CONFIG_VAR([build-mathvec], [$build_mathvec])
1803 AC_SUBST(libc_extra_cflags)
1804 AC_SUBST(libc_extra_cppflags)
1806 if test x$libc_cv_gcc_unwind_find_fde = xyes; then
1807 AC_DEFINE(EXPORT_UNWIND_FIND_FDE)
1809 AC_SUBST(libc_cv_gcc_unwind_find_fde)
1811 # A sysdeps configure fragment can reset this if IFUNC is not actually
1812 # usable even though the assembler knows how to generate the symbol type.
1813 if test x"$libc_cv_ld_gnu_indirect_function" = xyes; then
1814 AC_DEFINE(HAVE_IFUNC)
1816 LIBC_CONFIG_VAR([have-ifunc], [$libc_cv_ld_gnu_indirect_function])
1818 if test x"$libc_cv_gcc_indirect_function" = xyes; then
1819 AC_DEFINE(HAVE_GCC_IFUNC)
1822 # This is far from the AC_ARG_ENABLE that sets it so that a sysdeps
1823 # configure fragment can override the value to prevent this AC_DEFINE.
1825 if test "x$use_nscd" != xno; then
1826 AC_DEFINE([USE_NSCD])
1828 if test "x$build_nscd" = xdefault; then
1829 build_nscd=$use_nscd
1832 AC_SUBST(libc_cv_slibdir)
1833 AC_SUBST(libc_cv_rtlddir)
1834 AC_SUBST(libc_cv_complocaledir)
1835 AC_SUBST(libc_cv_sysconfdir)
1836 AC_SUBST(libc_cv_localstatedir)
1837 AC_SUBST(libc_cv_rootsbindir)
1839 if test x$use_ldconfig = xyes; then
1840 AC_DEFINE(USE_LDCONFIG)
1842 AC_SUBST(use_ldconfig)
1843 AC_SUBST(ldd_rewrite_script)
1848 AC_CACHE_CHECK([whether -fPIC is default], libc_cv_pic_default,
1849 [libc_cv_pic_default=yes
1850 cat > conftest.c <<EOF
1851 #if defined __PIC__ || defined __pic__ || defined PIC || defined pic
1852 # error PIC is default.
1855 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1856 libc_cv_pic_default=no
1859 AC_SUBST(libc_cv_pic_default)
1861 AC_CACHE_CHECK([whether -fPIE is default], libc_cv_cc_pie_default,
1862 [libc_cv_cc_pie_default=yes
1863 cat > conftest.c <<EOF
1864 #if defined __PIE__ || defined __pie__ || defined PIE || defined pie
1865 # error PIE is default.
1868 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1869 libc_cv_cc_pie_default=no
1872 libc_cv_pie_default=$libc_cv_cc_pie_default
1873 AC_SUBST(libc_cv_cc_pie_default)
1874 AC_SUBST(libc_cv_pie_default)
1876 # Set the `multidir' variable by grabbing the variable from the compiler.
1877 # We do it once and save the result in a generated makefile.
1878 libc_cv_multidir=`${CC-cc} $CFLAGS $CPPFLAGS -print-multi-directory`
1879 AC_SUBST(libc_cv_multidir)
1881 if test "$static_pie" = yes; then
1882 # The linker must support --no-dynamic-linker.
1883 if test "$libc_cv_no_dynamic_linker" != yes; then
1884 AC_MSG_ERROR([linker support for --no-dynamic-linker needed])
1887 libc_cv_pie_default=yes
1888 AC_DEFINE(ENABLE_STATIC_PIE)
1890 LIBC_CONFIG_VAR([enable-static-pie], [$static_pie])
1893 AC_SUBST(static_nss)
1897 dnl See sysdeps/mach/configure.ac for this variable.
1898 AC_SUBST(mach_interface_list)
1900 VERSION=`sed -n -e 's/^#define VERSION "\([^"]*\)"/\1/p' < $srcdir/version.h`
1901 RELEASE=`sed -n -e 's/^#define RELEASE "\([^"]*\)"/\1/p' < $srcdir/version.h`
1905 AC_CONFIG_FILES([config.make Makefile])
1906 AC_CONFIG_COMMANDS([default],[[
1907 case $CONFIG_FILES in *config.make*)
1908 echo "$config_vars" >> config.make;;
1910 test -d bits || mkdir bits]],[[config_vars='$config_vars']])