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 $srcdir; pwd -P`" = "`pwd -P`"; then
85 AC_MSG_ERROR([you must configure in a separate build directory])
88 # This will get text that should go into config.make.
91 # Check for a --with-gd argument and set libgd-LDFLAGS in config.make.
93 AS_HELP_STRING([--with-gd=DIR],
94 [find libgd include dir and library with prefix DIR]),
98 *) libgd_include="-I$withval/include"
99 libgd_ldflags="-L$withval/lib" ;;
102 AC_ARG_WITH([gd-include],
103 AS_HELP_STRING([--with-gd-include=DIR],
104 [find libgd include files in DIR]),
106 case "$with_gd_include" in
108 *) libgd_include="-I$withval" ;;
111 AC_ARG_WITH([gd-lib],
112 AS_HELP_STRING([--with-gd-lib=DIR],
113 [find libgd library files in DIR]),
115 case "$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 = $libgd_ldflags"
130 dnl Arguments to specify presence of other packages/features.
131 AC_ARG_WITH([binutils],
132 AS_HELP_STRING([--with-binutils=PATH],
133 [specify location of binutils (as and ld)]),
134 [path_binutils=$withval],
136 AC_ARG_WITH([selinux],
137 AS_HELP_STRING([--with-selinux],
138 [if building with SELinux support]),
139 [with_selinux=$withval],
142 AC_ARG_WITH([headers],
143 AS_HELP_STRING([--with-headers=PATH],
144 [location of system headers to use
145 (for example /usr/src/linux/include)
146 @<:@default=compiler default@:>@]),
147 [sysheaders=$withval],
151 AC_SUBST(use_default_link)
152 AC_ARG_WITH([default-link],
153 AS_HELP_STRING([--with-default-link],
154 [do not use explicit linker scripts]),
155 [use_default_link=$withval],
156 [use_default_link=default])
158 dnl Additional build flags injection.
159 AC_ARG_WITH([nonshared-cflags],
160 AS_HELP_STRING([--with-nonshared-cflags=CFLAGS],
161 [build nonshared libraries with additional CFLAGS]),
162 [extra_nonshared_cflags=$withval],
163 [extra_nonshared_cflags=])
164 AC_SUBST(extra_nonshared_cflags)
166 AC_ARG_ENABLE([sanity-checks],
167 AS_HELP_STRING([--disable-sanity-checks],
168 [really do not use threads (should not be used except in special situations) @<:@default=yes@:>@]),
169 [enable_sanity=$enableval],
172 AC_ARG_ENABLE([shared],
173 AS_HELP_STRING([--enable-shared],
174 [build shared library @<:@default=yes if GNU ld@:>@]),
177 AC_ARG_ENABLE([profile],
178 AS_HELP_STRING([--enable-profile],
179 [build profiled library @<:@default=no@:>@]),
180 [profile=$enableval],
182 AC_ARG_ENABLE([static-pie],
183 AS_HELP_STRING([--enable-static-pie],
184 [enable static PIE support and use it in the testsuite @<:@default=no@:>@]),
185 [static_pie=$enableval],
187 AC_ARG_ENABLE([timezone-tools],
188 AS_HELP_STRING([--disable-timezone-tools],
189 [do not install timezone tools @<:@default=install@:>@]),
190 [enable_timezone_tools=$enableval],
191 [enable_timezone_tools=yes])
192 AC_SUBST(enable_timezone_tools)
194 AC_ARG_ENABLE([hardcoded-path-in-tests],
195 AS_HELP_STRING([--enable-hardcoded-path-in-tests],
196 [hardcode newly built glibc path in tests @<:@default=no@:>@]),
197 [hardcoded_path_in_tests=$enableval],
198 [hardcoded_path_in_tests=no])
199 AC_SUBST(hardcoded_path_in_tests)
201 AC_ARG_ENABLE([hidden-plt],
202 AS_HELP_STRING([--disable-hidden-plt],
203 [do not hide internal function calls to avoid PLT]),
206 if test "x$hidden" = xno; then
210 AC_ARG_ENABLE([bind-now],
211 AS_HELP_STRING([--enable-bind-now],
212 [disable lazy relocations in DSOs]),
213 [bindnow=$enableval],
216 if test "x$bindnow" = xyes; then
220 dnl Build glibc with -fstack-protector, -fstack-protector-all, or
221 dnl -fstack-protector-strong.
222 AC_ARG_ENABLE([stack-protector],
223 AS_HELP_STRING([--enable-stack-protector=@<:@yes|no|all|strong@:>@],
224 [Use -fstack-protector[-all|-strong] to detect glibc buffer overflows]),
225 [enable_stack_protector=$enableval],
226 [enable_stack_protector=no])
227 case "$enable_stack_protector" in
228 all|yes|no|strong) ;;
229 *) AC_MSG_ERROR([Not a valid argument for --enable-stack-protector: \"$enable_stack_protector\"]);;
232 dnl On some platforms we cannot use dynamic loading. We must provide
233 dnl static NSS modules.
234 AC_ARG_ENABLE([static-nss],
235 AS_HELP_STRING([--enable-static-nss],
236 [build static NSS modules @<:@default=no@:>@]),
237 [static_nss=$enableval],
239 dnl Enable static NSS also if we build no shared objects.
240 if test x"$static_nss" = xyes || test x"$shared" = xno; then
242 AC_DEFINE(DO_STATIC_NSS)
245 AC_ARG_ENABLE([force-install],
246 AS_HELP_STRING([--disable-force-install],
247 [don't force installation of files from this package, even if they are older than the installed files]),
248 [force_install=$enableval],
250 AC_SUBST(force_install)
252 AC_ARG_ENABLE([maintainer-mode],
253 AS_HELP_STRING([--enable-maintainer-mode],
254 [enable make rules and dependencies not useful (and sometimes confusing) to the casual installer]),
255 [maintainer=$enableval],
258 dnl On some platforms we allow dropping compatibility with all kernel
260 AC_ARG_ENABLE([kernel],
261 AS_HELP_STRING([--enable-kernel=VERSION],
262 [compile for compatibility with kernel not older than VERSION]),
263 [minimum_kernel=$enableval],
265 dnl Prevent unreasonable values.
266 if test "$minimum_kernel" = yes || test "$minimum_kernel" = no; then
267 # Better nothing than this.
270 if test "$minimum_kernel" = current; then
271 minimum_kernel=`uname -r 2>/dev/null` || minimum_kernel=
275 dnl For the development we sometimes want gcc to issue even more warnings.
276 dnl This is not the default since many of the extra warnings are not
278 AC_ARG_ENABLE([all-warnings],
279 AS_HELP_STRING([--enable-all-warnings],
280 [enable all useful warnings gcc can issue]),
281 [all_warnings=$enableval],
283 AC_SUBST(all_warnings)
285 AC_ARG_ENABLE([werror],
286 AS_HELP_STRING([--disable-werror],
287 [do not build with -Werror]),
288 [enable_werror=$enableval],
290 AC_SUBST(enable_werror)
292 AC_ARG_ENABLE([multi-arch],
293 AS_HELP_STRING([--enable-multi-arch],
294 [enable single DSO with optimizations for multiple architectures]),
295 [multi_arch=$enableval],
296 [multi_arch=default])
298 AC_ARG_ENABLE([experimental-malloc],
299 AS_HELP_STRING([--disable-experimental-malloc],
300 [disable experimental malloc features]),
301 [experimental_malloc=$enableval],
302 [experimental_malloc=yes])
303 AC_SUBST(experimental_malloc)
305 AC_ARG_ENABLE([memory-tagging],
306 AS_HELP_STRING([--enable-memory-tagging],
307 [enable memory tagging if supported by the architecture @<:@default=no@:>@]),
308 [memory_tagging=$enableval],
310 if test "$memory_tagging" = yes; then
311 # Only enable this on architectures that support it.
318 AC_SUBST(memory_tagging)
320 AC_ARG_ENABLE([crypt],
321 AS_HELP_STRING([--disable-crypt],
322 [do not build nor install the passphrase hashing library, libcrypt]),
323 [build_crypt=$enableval],
325 AC_SUBST(build_crypt)
327 AC_ARG_ENABLE([nss-crypt],
328 AS_HELP_STRING([--enable-nss-crypt],
329 [enable libcrypt to use nss]),
330 [nss_crypt=$enableval],
332 if test x$build_libcrypt = xno && test x$nss_crypt = xyes; then
333 AC_MSG_WARN([--enable-nss-crypt has no effect when libcrypt is disabled])
336 if test x$nss_crypt = xyes; then
337 nss_includes=-I$(nss-config --includedir 2>/dev/null)
338 if test $? -ne 0; then
339 AC_MSG_ERROR([cannot find include directory with nss-config])
341 nspr_includes=-I$(nspr-config --includedir 2>/dev/null)
342 if test $? -ne 0; then
343 AC_MSG_ERROR([cannot find include directory with nspr-config])
346 CFLAGS="$CFLAGS $nss_includes $nspr_includes"
347 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
349 #include <nsslowhash.h>
350 void f (void) { NSSLOW_Init (); }])],
351 libc_cv_nss_crypt=yes,
353 cannot find NSS headers with lowlevel hash function interfaces]))
355 old_LDFLAGS="$LDFLAGS"
356 LIBS="$LIBS -lfreebl3"
357 AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
359 #include <nsslowhash.h>],
361 libc_cv_nss_crypt=yes,
363 cannot link program using lowlevel NSS hash functions]))
364 # Check to see if there is a static NSS cryptographic library.
365 # If there isn't then we can't link anything with libcrypt.a,
366 # and that might mean disabling some static tests.
367 LDFLAGS="$LDFLAGS -static"
368 AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
370 #include <nsslowhash.h>],
372 libc_cv_static_nss_crypt=yes,
373 libc_cv_static_nss_crypt=no)
374 LDFLAGS="$old_LDFLAGS"
379 libc_cv_static_nss_crypt=no
381 AC_SUBST(libc_cv_nss_crypt)
382 AC_SUBST(libc_cv_static_nss_crypt)
385 AC_ARG_ENABLE([systemtap],
386 [AS_HELP_STRING([--enable-systemtap],
387 [enable systemtap static probe points @<:@default=no@:>@])],
388 [systemtap=$enableval],
390 if test "x$systemtap" != xno; then
391 AC_CACHE_CHECK([for systemtap static probe support], libc_cv_sdt, [dnl
393 CFLAGS="-std=gnu11 $CFLAGS"
394 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <sys/sdt.h>
395 void foo (int i, void *p)
397 asm ("" STAP_PROBE_ASM (foo, bar, STAP_PROBE_ASM_TEMPLATE (2)) ""
398 :: STAP_PROBE_ASM_OPERANDS (2, i, p));
399 }]])], [libc_cv_sdt=yes], [libc_cv_sdt=no])
400 CFLAGS="$old_CFLAGS"])
401 if test $libc_cv_sdt = yes; then
402 AC_DEFINE([USE_STAP_PROBE])
403 elif test "x$systemtap" != xauto; then
404 AC_MSG_FAILURE([systemtap support needs sys/sdt.h with asm support])
408 AC_ARG_ENABLE([build-nscd],
409 [AS_HELP_STRING([--disable-build-nscd],
410 [disable building and installing the nscd daemon])],
411 [build_nscd=$enableval],
412 [build_nscd=default])
415 # Note the use of $use_nscd is near the bottom of the file.
416 AC_ARG_ENABLE([nscd],
417 [AS_HELP_STRING([--disable-nscd],
418 [library functions will not contact the nscd daemon])],
419 [use_nscd=$enableval],
422 AC_ARG_ENABLE([pt_chown],
423 [AS_HELP_STRING([--enable-pt_chown],
424 [Enable building and installing pt_chown])],
425 [build_pt_chown=$enableval],
427 AC_SUBST(build_pt_chown)
428 if test "$build_pt_chown" = yes; then
429 AC_DEFINE(HAVE_PT_CHOWN)
432 AC_ARG_ENABLE([tunables],
433 [AS_HELP_STRING([--enable-tunables],
434 [Enable tunables support. Known values are 'yes', 'no' and 'valstring'])],
435 [have_tunables=$enableval],
437 AC_SUBST(have_tunables)
438 if test "$have_tunables" = yes; then
439 AC_DEFINE(HAVE_TUNABLES)
442 # The abi-tags file uses a fairly simplistic model for name recognition that
443 # can't distinguish i486-pc-linux-gnu fully from i486-pc-gnu. So we mutate a
444 # $host_os of `gnu*' here to be `gnu-gnu*' just so that it can tell.
445 # This doesn't get used much beyond that, so it's fairly safe.
450 host_os=`echo $host_os | sed -e 's/gnu/gnu-gnu/'`
454 AC_ARG_ENABLE([mathvec],
455 [AS_HELP_STRING([--enable-mathvec],
456 [Enable building and installing mathvec @<:@default depends on architecture@:>@])],
457 [build_mathvec=$enableval],
458 [build_mathvec=notset])
460 AC_PREPROC_IFELSE([AC_LANG_PROGRAM([[]], [[
462 # error no CET compiler support
464 [libc_cv_compiler_default_cet=yes],
465 [libc_cv_compiler_default_cet=no])
468 AS_HELP_STRING([--enable-cet],
469 [enable Intel Control-flow Enforcement Technology (CET), x86 only]),
470 [enable_cet=$enableval],
471 [enable_cet=$libc_cv_compiler_default_cet])
474 AC_HELP_STRING([--disable-scv],
475 [syscalls will not use scv instruction, even if the kernel supports it, powerpc only]),
476 [use_scv=$enableval],
479 AS_IF([[test "$use_scv" != "no"]],[AC_DEFINE(USE_PPC_SCV)])
481 # We keep the original values in `$config_*' and never modify them, so we
482 # can write them unchanged into config.make. Everything else uses
483 # $machine, $vendor, and $os, and changes them whenever convenient.
484 config_machine=$host_cpu config_vendor=$host_vendor config_os=$host_os
486 # Don't allow vendor == "unknown"
487 test "$config_vendor" = unknown && config_vendor=
488 config_os="`echo $config_os | sed 's/^unknown-//'`"
490 # Some configurations imply other options.
493 # The configure fragment of a port can modify these to supplement
494 # or override the table in the case statement below. No fragment should
495 # ever change the config_* variables, however.
496 machine=$config_machine
497 vendor=$config_vendor
503 AS_HELP_STRING([--with-cpu=CPU], [select code for CPU variant]),
506 yes|'') AC_MSG_ERROR([--with-cpu requires an argument]) ;;
508 *) submachine="$withval" ;;
512 # An preconfigure script can set this when it wants to disable the sanity
516 # A preconfigure script for a system that may or may not use fpu
517 # sysdeps directories sets this to a preprocessor conditional for
518 # whether to use such directories.
521 dnl Let sysdeps/*/preconfigure act here.
522 LIBC_PRECONFIGURE([$srcdir], [for sysdeps])
526 ### By using the undocumented --enable-hacker-mode option for configure
527 ### one can skip this test to make the configuration not fail for unsupported
530 if test -z "$enable_hacker_mode" && test x"$libc_config_ok" != xyes; then
531 case "$machine-$host_os" in
536 *** The GNU C library is currently unavailable for this platform.
537 *** If you are interested in seeing glibc on this platform visit
538 *** the "How to submit a new port" in the wiki:
539 *** https://sourceware.org/glibc/wiki/#Development
540 *** and join the community!])
545 # Set base_machine if not set by a preconfigure fragment.
546 test -n "$base_machine" || base_machine=$machine
547 AC_SUBST(base_machine)
549 # Determine whether to use fpu or nofpu sysdeps directories.
550 AC_CACHE_CHECK([for use of fpu sysdeps directories],
551 libc_cv_with_fp, [dnl
552 cat > conftest.c <<EOF
556 # error "no hardware floating point"
560 if ${CC-cc} $CFLAGS $CPPFLAGS -S conftest.c -o conftest.s \
561 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
565 AC_SUBST(libc_cv_with_fp)
567 AC_CACHE_CHECK(for -fstack-protector, libc_cv_ssp, [dnl
568 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector],
573 AC_CACHE_CHECK(for -fstack-protector-strong, libc_cv_ssp_strong, [dnl
574 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-strong],
575 [libc_cv_ssp_strong=yes],
576 [libc_cv_ssp_strong=no])
579 AC_CACHE_CHECK(for -fstack-protector-all, libc_cv_ssp_all, [dnl
580 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-all],
581 [libc_cv_ssp_all=yes],
582 [libc_cv_ssp_all=no])
587 if test "$libc_cv_ssp" = yes; then
588 no_stack_protector="-fno-stack-protector -DSTACK_PROTECTOR_LEVEL=0"
589 AC_DEFINE(HAVE_CC_NO_STACK_PROTECTOR)
592 if test "$enable_stack_protector" = yes && test "$libc_cv_ssp" = yes; then
593 stack_protector="-fstack-protector"
594 AC_DEFINE(STACK_PROTECTOR_LEVEL, 1)
595 elif test "$enable_stack_protector" = all && test "$libc_cv_ssp_all" = yes; then
596 stack_protector="-fstack-protector-all"
597 AC_DEFINE(STACK_PROTECTOR_LEVEL, 2)
598 elif test "$enable_stack_protector" = strong && test "$libc_cv_ssp_strong" = yes; then
599 stack_protector="-fstack-protector-strong"
600 AC_DEFINE(STACK_PROTECTOR_LEVEL, 3)
602 stack_protector="-fno-stack-protector"
603 AC_DEFINE(STACK_PROTECTOR_LEVEL, 0)
605 AC_SUBST(libc_cv_ssp)
606 AC_SUBST(stack_protector)
607 AC_SUBST(no_stack_protector)
609 if test -n "$stack_protector"; then
610 dnl Don't run configure tests with stack-protection on, to avoid problems with
612 no_ssp=-fno-stack-protector
616 if test "$enable_stack_protector" != no; then
617 AC_MSG_ERROR([--enable-stack-protector=$enable_stack_protector specified, but specified level of stack protection is not supported by the compiler.])
621 # For the multi-arch option we need support in the assembler & linker.
622 AC_CACHE_CHECK([for assembler and linker STT_GNU_IFUNC support],
623 libc_cv_ld_gnu_indirect_function, [dnl
624 cat > conftest.S <<EOF
625 .type foo,%gnu_indirect_function
638 libc_cv_ld_gnu_indirect_function=no
639 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
640 -nostartfiles -nostdlib $no_ssp \
641 -o conftest conftest.S 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
642 # Do a link to see if the backend supports IFUNC relocs.
643 $READELF -r conftest 1>&AS_MESSAGE_LOG_FD
644 LC_ALL=C $READELF -Wr conftest | grep -q 'IRELATIVE\|R_SPARC_JMP_IREL' && {
645 libc_cv_ld_gnu_indirect_function=yes
650 # Check if gcc supports attribute ifunc as it is used in libc_ifunc macro.
651 AC_CACHE_CHECK([for gcc attribute ifunc support],
652 libc_cv_gcc_indirect_function, [dnl
653 cat > conftest.c <<EOF
654 extern int func (int);
655 int used_func (int a)
659 static void *resolver ()
663 extern __typeof (func) func __attribute__ ((ifunc ("resolver")));
665 libc_cv_gcc_indirect_function=no
666 if ${CC-cc} -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD \
667 2>&AS_MESSAGE_LOG_FD ; then
668 if $READELF -s conftest.o | grep IFUNC >/dev/null 2>&AS_MESSAGE_LOG_FD; then
669 libc_cv_gcc_indirect_function=yes
674 # Check if linker supports textrel relocation with ifunc (used on elf/tests).
675 # Note that it relies on libc_cv_ld_gnu_indirect_function test above.
676 AC_CACHE_CHECK([whether the linker supports textrels along with ifunc],
677 libc_cv_textrel_ifunc, [dnl
678 cat > conftest.S <<EOF
679 .type foo,%gnu_indirect_function
700 libc_cv_textrel_ifunc=no
701 if test $libc_cv_ld_gnu_indirect_function = yes; then
702 if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp -pie -o conftest conftest.S); then
703 libc_cv_textrel_ifunc=yes
707 AC_SUBST(libc_cv_textrel_ifunc)
709 # Check if CC supports attribute retain as it is used in attribute_used_retain macro.
710 AC_CACHE_CHECK([for GNU attribute retain support],
711 libc_cv_gnu_retain, [dnl
712 cat > conftest.c <<EOF
713 static int var __attribute__ ((used, retain, section ("__libc_atexit")));
715 libc_cv_gnu_retain=no
716 if ${CC-cc} -Werror -c conftest.c -o /dev/null 1>&AS_MESSAGE_LOG_FD \
717 2>&AS_MESSAGE_LOG_FD ; then
718 libc_cv_gnu_retain=yes
721 if test $libc_cv_gnu_retain = yes; then
722 AC_DEFINE(HAVE_GNU_RETAIN)
724 LIBC_CONFIG_VAR([have-gnu-retain], [$libc_cv_gnu_retain])
726 # Check if gcc warns about alias for function with incompatible types.
727 AC_CACHE_CHECK([if compiler warns about alias for function with incompatible types],
728 libc_cv_gcc_incompatible_alias, [dnl
729 cat > conftest.c <<EOF
730 int __redirect_foo (const void *s, int c);
732 __typeof (__redirect_foo) *foo_impl (void) __asm__ ("foo");
733 __typeof (__redirect_foo) *foo_impl (void)
738 extern __typeof (__redirect_foo) foo_alias __attribute__ ((alias ("foo")));
740 libc_cv_gcc_incompatible_alias=yes
741 if ${CC-cc} -Werror -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
742 libc_cv_gcc_incompatible_alias=no
746 if test x"$libc_cv_ld_gnu_indirect_function" != xyes; then
747 if test x"$multi_arch" = xyes; then
748 AC_MSG_ERROR([--enable-multi-arch support requires assembler and linker support])
753 if test x"$libc_cv_gcc_indirect_function" != xyes; then
754 # GCC 8+ emits a warning for alias with incompatible types and it might
755 # fail to build ifunc resolvers aliases to either weak or internal
756 # symbols. Disables multiarch build in this case.
757 if test x"$libc_cv_gcc_incompatible_alias" == xyes; then
758 AC_MSG_WARN([gcc emits a warning for alias between functions of incompatible types])
759 if test x"$multi_arch" = xyes; then
760 AC_MSG_ERROR([--enable-multi-arch support requires a gcc with gnu-indirect-function support])
762 AC_MSG_WARN([Multi-arch is disabled.])
764 elif test x"$multi_arch" = xyes; then
765 AC_MSG_WARN([--enable-multi-arch support recommends a gcc with gnu-indirect-function support.
766 Please use a gcc which supports it by default or configure gcc with --enable-gnu-indirect-function])
770 if test x"$multi_arch" != xno; then
771 multi_arch_d=/multiarch
774 # Compute the list of sysdep directories for this configuration.
775 # This can take a while to compute.
776 sysdep_dir=$srcdir/sysdeps
777 AC_MSG_CHECKING(sysdep dirs)
778 dnl We need to use [ and ] for other purposes for a while now.
780 # Make sco3.2v4 become sco3.2.4 and sunos4.1.1_U1 become sunos4.1.1.U1.
781 os="`echo $os | sed 's/\([0-9A-Z]\)[v_]\([0-9A-Z]\)/\1.\2/g'`"
783 test "x$base_os" != x || case "$os" in
790 # For sunos4.1.1, try sunos4.1.1, then sunos4.1, then sunos4, then sunos.
793 while o=`echo $tail | sed 's/\.[^.]*$//'`; test $o != $tail; do
797 o=`echo $tail | sed 's/[0-9]*$//'`
798 if test $o != $tail; then
801 # For linux-gnu, try linux-gnu, then linux.
802 o=`echo $tail | sed 's/-.*$//'`
803 if test $o != $tail; then
807 # For unix/sysv/sysv4, try unix/sysv/sysv4, then unix/sysv, then unix.
810 while b=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$b"; do
816 # For sparc/sparc32, try sparc/sparc32 and then sparc.
818 tail=$machine${submachine:+/$submachine}
819 while m=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$m"; do
821 # Prepend the machine's FPU directory unless the architecture specific
822 # preconfigure disables it.
823 if test "$libc_cv_with_fp" = yes; then
828 # For each machine term, try it with and then without /multiarch.
829 for try_fpu in $maybe_fpu ''; do
830 for try_multi in $multi_arch_d ''; do
831 mach="$mach /$1$try_fpu$try_multi"
837 dnl We are done with glob and regexp uses of [ and ]; return to autoconf.
840 # Find what sysdep directories exist.
842 for b in $base ''; do
843 for m0 in $mach ''; do
844 for v in /$vendor ''; do
845 test "$v" = / && continue
846 for o in /$ostry ''; do
847 test "$o" = / && continue
848 for m in $mach ''; do
849 try_suffix="$m0$b$v$o$m"
850 if test -n "$try_suffix"; then
851 try_srcdir="${srcdir}/"
852 try="sysdeps$try_suffix"
853 test -n "$enable_debug_configure" &&
854 echo "$0 [DEBUG]: try $try" >&2
855 if test -d "$try_srcdir$try"; then
856 sysnames="$sysnames $try"
857 { test -n "$o" || test -n "$b"; } && os_used=t
858 { test -n "$m" || test -n "$m0"; } && machine_used=t
860 x*/$submachine) submachine_used=t ;;
870 # If the assembler supports gnu_indirect_function symbol type and the
871 # architecture supports multi-arch, we enable multi-arch by default.
876 test x"$multi_arch" = xdefault && multi_arch=no
879 if test x"$multi_arch" != xno; then
880 AC_DEFINE(USE_MULTIARCH)
884 if test -z "$os_used" && test "$os" != none; then
885 AC_MSG_ERROR(Operating system $os is not supported.)
887 if test -z "$machine_used" && test "$machine" != none; then
888 AC_MSG_ERROR(The $machine is not supported.)
890 if test -z "$submachine_used" && test -n "$submachine"; then
891 AC_MSG_ERROR(The $submachine subspecies of $host_cpu is not supported.)
895 # We have now validated the configuration.
897 # Expand the list of system names into a full list of directories
898 # from each element's parent name and Implies file (if present).
901 while test $# -gt 0; do
905 case " $names " in *" $name "*)
906 # Already in the list.
910 # Report each name as we discover it, so there is no long pause in output.
911 echo $ECHO_N "$name $ECHO_C" >&AS_MESSAGE_FD
913 name_base=`echo $name | sed -e 's@\(.*sysdeps\)/.*@\1@'`
917 *) xsrcdir=$srcdir/ ;;
919 test -n "$enable_debug_configure" &&
920 echo "[DEBUG]: name/Implies $xsrcdir$name/Implies" >&2
922 for implies_file in Implies Implies-before Implies-after; do
923 implies_type=`echo $implies_file | sed s/-/_/`
924 eval ${implies_type}=
925 if test -f $xsrcdir$name/$implies_file; then
926 # Collect more names from the `Implies' file (removing comments).
927 implied_candidate="`sed 's/#.*$//' < $xsrcdir$name/$implies_file`"
928 for x in $implied_candidate; do
930 if test -d $xsrcdir$name_base/$x; then
931 eval "${implies_type}=\"\$${implies_type} \$name_base/\$x\""
936 test -n "$enable_debug_configure" &&
937 echo "[DEBUG]: $name $implies_file $x try() {$try_srcdir}$try" >&2
938 if test $try != $xsrcdir$name_base/$x && test -d $try_srcdir$try;
940 eval "${implies_type}=\"\$${implies_type} \$try\""
943 if test $found = no; then
944 AC_MSG_WARN($name/$implies_file specifies nonexistent $x)
950 # Add NAME to the list of names.
953 # Find the parent of NAME, using the empty string if it has none.
955 parent="`echo $name | sed -n -e 's=/[^/]*$==' -e '/sysdeps$/q' -e p`"
958 test -n "$enable_debug_configure" &&
959 echo "[DEBUG]: $name Implies='$Implies' rest='$*' parent='$parent' \
960 Implies_before='$Implies_before' Implies_after='$Implies_after'" >&2
962 # Add the names implied by NAME, and NAME's parent (if it has one), to
963 # the list of names to be processed (the argument list). We prepend the
964 # implied names to the list and append the parent. We want implied
965 # directories to come before further directories inferred from the
966 # configuration components; this ensures that for sysv4, unix/common
967 # (implied by unix/sysv/sysv4) comes before unix/sysv (in ostry (here $*)
969 sysnames="`echo $Implies $* $Implies_before $parent $Implies_after`"
970 test -n "$sysnames" && set $sysnames
973 # Add the default directories.
974 default_sysnames="sysdeps/generic"
975 sysnames="$names $default_sysnames"
977 # The other names were emitted during the scan.
978 AC_MSG_RESULT($default_sysnames)
984 if test "$INSTALL" = "${srcdir}/scripts/install-sh -c"; then
985 # The makefiles need to use a different form to find it in $srcdir.
986 INSTALL='\$(..)./scripts/install-sh -c'
992 # Accept binutils 2.25 or newer.
993 AC_CHECK_PROG_VER(AS, $AS, --version,
994 [GNU assembler.* \([0-9]*\.[0-9.]*\)],
995 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
996 AS=: critic_missing="$critic_missing as")
998 if test -n "`$LD --version | sed -n 's/^GNU \(gold\).*$/\1/p'`"; then
999 # Accept gold 1.14 or higher
1000 AC_CHECK_PROG_VER(LD, $LD, --version,
1001 [GNU gold.* \([0-9][0-9]*\.[0-9.]*\)],
1002 [1.1[4-9]*|1.[2-9][0-9]*|1.1[0-9][0-9]*|[2-9].*|[1-9][0-9]*],
1003 LD=: critic_missing="$critic_missing GNU gold")
1005 AC_CHECK_PROG_VER(LD, $LD, --version,
1006 [GNU ld.* \([0-9][0-9]*\.[0-9.]*\)],
1007 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
1008 LD=: critic_missing="$critic_missing GNU ld")
1011 # These programs are version sensitive.
1012 AC_CHECK_PROG_VER(MAKE, gnumake gmake make, --version,
1013 [GNU Make[^0-9]*\([0-9][0-9.]*\)],
1014 [[4-9].* | [1-9][0-9]*], critic_missing="$critic_missing make")
1016 AC_CHECK_PROG_VER(MSGFMT, gnumsgfmt gmsgfmt msgfmt, --version,
1017 [GNU gettext.* \([0-9]*\.[0-9.]*\)],
1018 [0.10.3[6-9]* | 0.10.[4-9][0-9]* | 0.1[1-9]* | 0.[2-9][0-9]* | [1-9].*],
1019 MSGFMT=: aux_missing="$aux_missing msgfmt")
1020 AC_CHECK_PROG_VER(MAKEINFO, makeinfo, --version,
1021 [GNU texinfo.* \([0-9][0-9.]*\)],
1022 [4.[7-9]*|4.[1-9][0-9]*|[5-9].*],
1023 MAKEINFO=: aux_missing="$aux_missing makeinfo")
1024 AC_CHECK_PROG_VER(SED, sed, --version,
1025 [GNU sed[^0-9]* \([0-9]*\.[0-9.]*\)],
1026 [3.0[2-9]*|3.[1-9]*|[4-9]*],
1027 SED=: aux_missing="$aux_missing sed")
1028 AC_CHECK_PROG_VER(AWK, gawk, --version,
1029 [GNU Awk[^0-9]*\([0-9][0-9.]*\)],
1030 [3.1.[2-9]*|3.[2-9]*|[4-9]*], critic_missing="$critic_missing gawk")
1031 AC_CHECK_PROG_VER(BISON, bison, --version,
1032 [bison (GNU Bison) \([0-9]*\.[0-9.]*\)],
1033 [2.7*|[3-9].*|[1-9][0-9]*], critic_missing="$critic_missing bison")
1035 AC_CACHE_CHECK([if $CC is sufficient to build libc], libc_cv_compiler_ok, [
1036 AC_PREPROC_IFELSE([AC_LANG_PROGRAM([[]], [[
1037 #if !defined __GNUC__ || __GNUC__ < 6 || (__GNUC__ == 6 && __GNUC_MINOR__ < 2)
1038 #error insufficient compiler
1040 [libc_cv_compiler_ok=yes],
1041 [libc_cv_compiler_ok=no])])
1042 AS_IF([test $libc_cv_compiler_ok != yes],
1043 [critic_missing="$critic_missing compiler"])
1045 AC_CHECK_TOOL(NM, nm, false)
1047 if test "x$maintainer" = "xyes"; then
1048 AC_CHECK_PROGS(AUTOCONF, autoconf, no)
1049 case "x$AUTOCONF" in
1050 xno|x|x:) AUTOCONF=no ;;
1053 whether $AUTOCONF${ACFLAGS:+ }$ACFLAGS works, libc_cv_autoconf_works, [dnl
1054 if (cd $srcdir; $AUTOCONF $ACFLAGS configure.ac > /dev/null 2>&1); then
1055 libc_cv_autoconf_works=yes
1057 libc_cv_autoconf_works=no
1059 test $libc_cv_autoconf_works = yes || AUTOCONF=no
1062 if test "x$AUTOCONF" = xno; then
1063 aux_missing="$aux_missing autoconf"
1069 # Check for python3 if available, or else python.
1070 AC_CHECK_PROG_VER(PYTHON_PROG, python3 python, --version,
1071 [Python \([0-9][0-9.]*\)],
1072 [3.[4-9]*|3.[1-9][0-9]*|[4-9].*|[1-9][0-9]*],
1073 critic_missing="$critic_missing python")
1074 PYTHON="$PYTHON_PROG -B"
1077 test -n "$critic_missing" && AC_MSG_ERROR([
1078 *** These critical programs are missing or too old:$critic_missing
1079 *** Check the INSTALL file for required versions.])
1081 test -n "$aux_missing" && AC_MSG_WARN([
1082 *** These auxiliary programs are missing or incompatible versions:$aux_missing
1083 *** some features or tests will be disabled.
1084 *** Check the INSTALL file for required versions.])
1086 # if using special system headers, find out the compiler's sekrit
1087 # header directory and add that to the list. NOTE: Only does the right
1088 # thing on a system that doesn't need fixincludes. (Not presently a problem.)
1089 if test -n "$sysheaders"; then
1090 SYSINCLUDES=-nostdinc
1091 for d in include include-fixed; do
1092 i=`$CC -print-file-name="$d"` && test "x$i" != x && test "x$i" != "x$d" &&
1093 SYSINCLUDES="$SYSINCLUDES -isystem $i"
1095 SYSINCLUDES="$SYSINCLUDES \
1096 -isystem `echo $sysheaders | sed 's/:/ -isystem /g'`"
1097 if test -n "$CXX"; then
1099 for cxxheaders in `$CXX -v -S -x c++ /dev/null -o /dev/null 2>&1 \
1100 | sed -n -e '1,/#include/d' -e 's/^ \(\/.*\/[cg]++\)/\1/p'`; do
1101 test "x$cxxheaders" != x &&
1102 CXX_SYSINCLUDES="$CXX_SYSINCLUDES -isystem $cxxheaders"
1106 AC_SUBST(SYSINCLUDES)
1107 AC_SUBST(CXX_SYSINCLUDES)
1109 # Obtain some C++ header file paths. This is used to make a local
1110 # copy of those headers in Makerules.
1111 if test -n "$CXX"; then
1112 find_cxx_header () {
1113 echo "#include <$1>" | $CXX -M -MP -x c++ - 2>/dev/null \
1114 | sed -n "\,$1:,{s/:\$//;p}"
1116 CXX_CSTDLIB_HEADER="$(find_cxx_header cstdlib)"
1117 CXX_CMATH_HEADER="$(find_cxx_header cmath)"
1118 CXX_BITS_STD_ABS_H="$(find_cxx_header bits/std_abs.h)"
1120 AC_SUBST(CXX_CSTDLIB_HEADER)
1121 AC_SUBST(CXX_CMATH_HEADER)
1122 AC_SUBST(CXX_BITS_STD_ABS_H)
1124 # Test if LD_LIBRARY_PATH contains the notation for the current directory
1125 # since this would lead to problems installing/building glibc.
1126 # LD_LIBRARY_PATH contains the current directory if one of the following
1128 # - one of the terminals (":" and ";") is the first or last sign
1129 # - two terminals occur directly after each other
1130 # - the path contains an element with a dot in it
1131 AC_MSG_CHECKING(LD_LIBRARY_PATH variable)
1133 case ${LD_LIBRARY_PATH} in
1134 [:\;]* | *[:\;] | *[:\;][:\;]* | *[:\;]. | .[:\;]*| . | *[:\;].[:\;]* )
1135 ld_library_path_setting="contains current directory"
1138 ld_library_path_setting="ok"
1142 AC_MSG_RESULT($ld_library_path_setting)
1143 if test "$ld_library_path_setting" != "ok"; then
1145 *** LD_LIBRARY_PATH shouldn't contain the current directory when
1146 *** building glibc. Please change the environment variable
1147 *** and run configure again.])
1150 AC_PATH_PROG(BASH_SHELL, bash, no)
1152 AC_PATH_PROG(PERL, perl, no)
1153 if test "$PERL" != no &&
1154 (eval `$PERL -V:apiversion`; test `expr "$apiversion" \< 5` -ne 0); then
1157 AC_PATH_PROG(INSTALL_INFO, install-info, no,
1158 $PATH:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin)
1160 AC_CACHE_CHECK(for .set assembler directive, libc_cv_asm_set_directive, [dnl
1161 cat > conftest.s <<EOF
1164 .set glibc_conftest_frobozz,foo
1165 .globl glibc_conftest_frobozz
1167 # The alpha-dec-osf1 assembler gives only a warning for `.set'
1168 # (but it doesn't work), so we must do a linking check to be sure.
1169 cat > conftest1.c <<\EOF
1170 extern int glibc_conftest_frobozz;
1171 void _start() { glibc_conftest_frobozz = 1; }
1173 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
1174 -nostartfiles -nostdlib $no_ssp \
1175 -o conftest conftest.s conftest1.c 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
1176 libc_cv_asm_set_directive=yes
1178 libc_cv_asm_set_directive=no
1181 if test $libc_cv_asm_set_directive = yes; then
1182 AC_DEFINE(HAVE_ASM_SET_DIRECTIVE)
1185 AC_CACHE_CHECK(linker support for protected data symbol,
1186 libc_cv_protected_data,
1187 [cat > conftest.c <<EOF
1188 int bar __attribute__ ((visibility ("protected"))) = 1;
1190 libc_cv_protected_data=no
1191 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -o conftest.so); then
1192 cat > conftest.c <<EOF
1194 int main (void) { return bar; }
1196 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp conftest.c -o conftest conftest.so); then
1197 libc_cv_protected_data=yes
1202 AC_SUBST(libc_cv_protected_data)
1204 AC_CACHE_CHECK(linker support for INSERT in linker script,
1206 [cat > conftest.c <<EOF
1207 const int __attribute__ ((section(".bar"))) bar = 0x12345678;
1208 int test (void) { return bar; }
1210 cat > conftest.t <<EOF
1215 INSERT AFTER .rela.dyn;
1218 if AC_TRY_COMMAND([${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -Wl,-T,conftest.t -o conftest.so]); then
1223 AC_SUBST(libc_cv_insert)
1225 AC_CACHE_CHECK(for broken __attribute__((alias())),
1226 libc_cv_broken_alias_attribute,
1227 [cat > conftest.c <<EOF
1228 extern int foo (int x) __asm ("xyzzy");
1229 int bar (int x) { return x; }
1230 extern __typeof (bar) foo __attribute ((weak, alias ("bar")));
1232 extern __typeof (dfoo) dfoo __asm ("abccb");
1235 libc_cv_broken_alias_attribute=yes
1236 if AC_TRY_COMMAND(${CC-cc} -Werror -S conftest.c -o conftest.s 1>&AS_MESSAGE_LOG_FD); then
1237 if grep 'xyzzy' conftest.s >/dev/null &&
1238 grep 'abccb' conftest.s >/dev/null; then
1239 libc_cv_broken_alias_attribute=no
1242 rm -f conftest.c conftest.s
1244 if test $libc_cv_broken_alias_attribute = yes; then
1245 AC_MSG_ERROR(working alias attribute support required)
1248 AC_CACHE_CHECK(whether to put _rtld_local into .sdata section,
1249 libc_cv_have_sdata_section,
1250 [echo "int i;" > conftest.c
1251 libc_cv_have_sdata_section=no
1252 if ${CC-cc} $LDFLAGS -fPIC -shared -Wl,--verbose conftest.c -o conftest.so 2>&1 \
1253 | grep '\.sdata' >/dev/null; then
1254 libc_cv_have_sdata_section=yes
1256 rm -f conftest.c conftest.so
1258 if test $libc_cv_have_sdata_section = yes; then
1259 AC_DEFINE(HAVE_SDATA_SECTION)
1262 AC_CACHE_CHECK(for libunwind-support in compiler,
1263 libc_cv_cc_with_libunwind, [
1264 cat > conftest.c <<EOF
1265 int main (void) { return 0; }
1267 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -static -o conftest \
1268 conftest.c -v 2>&1 >/dev/null | grep ' -lunwind ' >/dev/null; then
1269 libc_cv_cc_with_libunwind=yes
1271 libc_cv_cc_with_libunwind=no
1274 AC_SUBST(libc_cv_cc_with_libunwind)
1275 if test $libc_cv_cc_with_libunwind = yes; then
1276 AC_DEFINE(HAVE_CC_WITH_LIBUNWIND)
1280 AC_CACHE_CHECK(whether --noexecstack is desirable for .S files,
1281 libc_cv_as_noexecstack, [dnl
1282 cat > conftest.c <<EOF
1285 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS
1286 -S -o conftest.s conftest.c 1>&AS_MESSAGE_LOG_FD]) \
1287 && grep .note.GNU-stack conftest.s >/dev/null \
1288 && AC_TRY_COMMAND([${CC-cc} $ASFLAGS -Wa,--noexecstack
1289 -c -o conftest.o conftest.s 1>&AS_MESSAGE_LOG_FD])
1291 libc_cv_as_noexecstack=yes
1293 libc_cv_as_noexecstack=no
1296 if test $libc_cv_as_noexecstack = yes; then
1297 ASFLAGS_config="$ASFLAGS_config -Wa,--noexecstack"
1299 AC_SUBST(ASFLAGS_config)
1301 AC_CACHE_CHECK(for -z combreloc,
1302 libc_cv_z_combreloc, [dnl
1303 cat > conftest.c <<EOF
1304 extern int bar (int);
1306 int foo (void) { return bar (mumble); }
1308 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1309 -fPIC -shared $no_ssp -o conftest.so conftest.c
1310 -nostdlib -nostartfiles
1311 -Wl,-z,combreloc 1>&AS_MESSAGE_LOG_FD])
1313 dnl The following test is a bit weak. We must use a tool which can test
1314 dnl cross-platform since the gcc used can be a cross compiler. Without
1315 dnl introducing new options this is not easily doable. Instead use a tool
1316 dnl which always is cross-platform: readelf. To detect whether -z combreloc
1317 dnl look for a section named .rel.dyn or .rela.dyn.
1318 if $READELF -S conftest.so | grep -E '.rela?.dyn' > /dev/null; then
1319 libc_cv_z_combreloc=yes
1321 libc_cv_z_combreloc=no
1324 libc_cv_z_combreloc=no
1327 if test "$libc_cv_z_combreloc" = yes; then
1328 AC_DEFINE(HAVE_Z_COMBRELOC)
1330 AC_SUBST(libc_cv_z_combreloc)
1332 LIBC_LINKER_FEATURE([-z execstack], [-Wl,-z,execstack],
1333 [libc_cv_z_execstack=yes], [libc_cv_z_execstack=no])
1334 AC_SUBST(libc_cv_z_execstack)
1336 LIBC_LINKER_FEATURE([-z start-stop-gc], [-Wl,-z,start-stop-gc],
1337 [libc_cv_z_start_stop_gc=yes], [libc_cv_z_start_stop_gc=no])
1338 LIBC_CONFIG_VAR([have-z-start-stop-gc], [$libc_cv_z_start_stop_gc])
1340 LIBC_LINKER_FEATURE([--no-dynamic-linker],
1341 [-Wl,--no-dynamic-linker],
1342 [libc_cv_no_dynamic_linker=yes],
1343 [libc_cv_no_dynamic_linker=no])
1344 LIBC_CONFIG_VAR([have-no-dynamic-linker], [$libc_cv_no_dynamic_linker])
1346 AC_CACHE_CHECK(for -static-pie, libc_cv_static_pie, [dnl
1347 LIBC_TRY_CC_OPTION([-static-pie],
1348 [libc_cv_static_pie=yes],
1349 [libc_cv_static_pie=no])
1351 LIBC_CONFIG_VAR([have-static-pie], [$libc_cv_static_pie])
1353 AC_CACHE_CHECK(for -fpie, libc_cv_fpie, [dnl
1354 LIBC_TRY_CC_OPTION([-fpie], [libc_cv_fpie=yes], [libc_cv_fpie=no])
1357 AC_SUBST(libc_cv_fpie)
1359 AC_CACHE_CHECK(for --hash-style option,
1360 libc_cv_hashstyle, [dnl
1361 cat > conftest.c <<EOF
1362 int _start (void) { return 42; }
1364 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp
1365 -fPIC -shared -o conftest.so conftest.c
1366 -Wl,--hash-style=both -nostdlib 1>&AS_MESSAGE_LOG_FD])
1368 libc_cv_hashstyle=yes
1370 libc_cv_hashstyle=no
1373 AC_SUBST(libc_cv_hashstyle)
1375 # The linker's default -shared behavior is good enough if it
1376 # does these things that our custom linker scripts ensure that
1377 # all allocated NOTE sections come first.
1378 if test "$use_default_link" = default; then
1379 AC_CACHE_CHECK([for sufficient default -shared layout],
1380 libc_cv_use_default_link, [dnl
1381 libc_cv_use_default_link=no
1382 cat > conftest.s <<\EOF
1383 .section .note.a,"a",%note
1388 .section .note.b,"a",%note
1394 if AC_TRY_COMMAND([dnl
1395 ${CC-cc} $ASFLAGS -shared -o conftest.so conftest.s 1>&AS_MESSAGE_LOG_FD]) &&
1396 ac_try=`$READELF -S conftest.so | sed -n \
1398 s/^ *\[ *[1-9][0-9]*\] *\([^ ][^ ]*\) *\([^ ][^ ]*\) .*$/\2 \1/
1404 libc_seen_a=no libc_seen_b=no
1406 while test $# -ge 2 -a "$1" = NOTE; do
1408 .note.a) libc_seen_a=yes ;;
1409 .note.b) libc_seen_b=yes ;;
1413 case "$libc_seen_a$libc_seen_b" in
1415 libc_cv_use_default_link=yes
1418 echo >&AS_MESSAGE_LOG_FD "\
1419 $libc_seen_a$libc_seen_b from:
1425 use_default_link=$libc_cv_use_default_link
1428 AC_CACHE_CHECK(for GLOB_DAT reloc,
1429 libc_cv_has_glob_dat, [dnl
1430 cat > conftest.c <<EOF
1432 int foo (void) { return mumble; }
1434 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1435 -fPIC -shared -o conftest.so conftest.c
1436 -nostdlib -nostartfiles $no_ssp
1437 1>&AS_MESSAGE_LOG_FD])
1439 dnl look for GLOB_DAT relocation.
1440 if $READELF -rW conftest.so | grep '_GLOB_DAT' > /dev/null; then
1441 libc_cv_has_glob_dat=yes
1443 libc_cv_has_glob_dat=no
1446 libc_cv_has_glob_dat=no
1449 AC_SUBST(libc_cv_has_glob_dat)
1451 AC_CACHE_CHECK(for -fno-toplevel-reorder -fno-section-anchors, libc_cv_fno_toplevel_reorder, [dnl
1452 cat > conftest.c <<EOF
1455 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fno-toplevel-reorder -fno-section-anchors
1456 conftest.c 1>&AS_MESSAGE_LOG_FD])
1458 libc_cv_fno_toplevel_reorder=yes
1460 libc_cv_fno_toplevel_reorder=no
1463 if test $libc_cv_fno_toplevel_reorder = yes; then
1464 fno_unit_at_a_time="-fno-toplevel-reorder -fno-section-anchors"
1466 fno_unit_at_a_time=-fno-unit-at-a-time
1468 AC_SUBST(fno_unit_at_a_time)
1470 AC_CACHE_CHECK([for -mtls-dialect=gnu2], libc_cv_mtls_dialect_gnu2,
1472 cat > conftest.c <<EOF
1479 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fPIC -mtls-dialect=gnu2
1480 conftest.c 1>&AS_MESSAGE_LOG_FD])
1482 libc_cv_mtls_dialect_gnu2=yes
1484 libc_cv_mtls_dialect_gnu2=no
1487 AC_SUBST(libc_cv_mtls_dialect_gnu2)
1488 LIBC_CONFIG_VAR([have-mtls-dialect-gnu2], [$libc_cv_mtls_dialect_gnu2])
1490 AC_CACHE_CHECK(whether cc puts quotes around section names,
1491 libc_cv_have_section_quotes,
1492 [cat > conftest.c <<EOF
1493 static const int foo
1494 __attribute__ ((section ("bar"))) = 1;
1496 if ${CC-cc} -S conftest.c -o conftest.s; then
1497 if grep '\.section.*"bar"' conftest.s >/dev/null; then
1498 libc_cv_have_section_quotes=yes
1500 libc_cv_have_section_quotes=no
1503 libc_cv_have_section_quotes=unknown
1505 rm -f conftest.{c,s}
1507 if test $libc_cv_have_section_quotes = yes; then
1508 AC_DEFINE(HAVE_SECTION_QUOTES)
1511 AC_CACHE_CHECK(for __builtin_memset, libc_cv_gcc_builtin_memset, [dnl
1512 cat > conftest.c <<\EOF
1515 __builtin_memset (x, 0, 1000);
1519 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "memset" > /dev/null]);
1521 libc_cv_gcc_builtin_memset=no
1523 libc_cv_gcc_builtin_memset=yes
1526 if test "$libc_cv_gcc_builtin_memset" = yes ; then
1527 AC_DEFINE(HAVE_BUILTIN_MEMSET)
1530 AC_CACHE_CHECK(for redirection of built-in functions, libc_cv_gcc_builtin_redirection, [dnl
1531 cat > conftest.c <<\EOF
1532 extern char *strstr (const char *, const char *) __asm ("my_strstr");
1533 char *foo (const char *a, const char *b)
1535 return __builtin_strstr (a, b);
1539 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "my_strstr" > /dev/null]);
1541 libc_cv_gcc_builtin_redirection=yes
1543 libc_cv_gcc_builtin_redirection=no
1546 if test "$libc_cv_gcc_builtin_redirection" = no; then
1547 AC_MSG_ERROR([support for the symbol redirection needed])
1550 dnl Determine how to disable generation of FMA instructions.
1551 AC_CACHE_CHECK([for compiler option to disable generation of FMA instructions],
1552 libc_cv_cc_nofma, [dnl
1554 for opt in -ffp-contract=off -mno-fused-madd; do
1555 LIBC_TRY_CC_OPTION([$opt], [libc_cv_cc_nofma=$opt; break])
1557 AC_SUBST(libc_cv_cc_nofma)
1559 if test -n "$submachine"; then
1560 AC_CACHE_CHECK([for compiler option for CPU variant],
1561 libc_cv_cc_submachine, [dnl
1562 libc_cv_cc_submachine=no
1563 for opt in "-march=$submachine" "-mcpu=$submachine"; do
1564 LIBC_TRY_CC_OPTION([$opt], [
1565 libc_cv_cc_submachine="$opt"
1568 if test "x$libc_cv_cc_submachine" = xno; then
1569 AC_MSG_ERROR([${CC-cc} does not support $submachine])
1572 AC_SUBST(libc_cv_cc_submachine)
1574 AC_CACHE_CHECK(if $CC accepts -fno-tree-loop-distribute-patterns with \
1575 __attribute__ ((__optimize__)), libc_cv_cc_loop_to_function, [dnl
1576 cat > conftest.c <<EOF
1578 __attribute__ ((__optimize__ ("-fno-tree-loop-distribute-patterns")))
1581 libc_cv_cc_loop_to_function=no
1582 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -c conftest.c])
1584 libc_cv_cc_loop_to_function=yes
1587 if test $libc_cv_cc_loop_to_function = yes; then
1588 AC_DEFINE(HAVE_CC_INHIBIT_LOOP_TO_LIBCALL)
1590 AC_SUBST(libc_cv_cc_loop_to_function)
1592 dnl Check whether we have the gd library available.
1593 AC_MSG_CHECKING(for libgd)
1594 if test "$with_gd" != "no"; then
1595 old_CFLAGS="$CFLAGS"
1596 CFLAGS="$CFLAGS $libgd_include"
1597 old_LDFLAGS="$LDFLAGS"
1598 LDFLAGS="$LDFLAGS $libgd_ldflags"
1600 LIBS="$LIBS -lgd -lpng -lz -lm"
1601 AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <gd.h>]], [[gdImagePng (0, 0)]])],
1602 [LIBGD=yes], [LIBGD=no])
1603 CFLAGS="$old_CFLAGS"
1604 LDFLAGS="$old_LDFLAGS"
1609 AC_MSG_RESULT($LIBGD)
1613 if test x$with_selinux = xno ; then
1616 # See if we have the SELinux library
1617 AC_CHECK_LIB(selinux, is_selinux_enabled,
1618 have_selinux=yes, have_selinux=no)
1619 if test x$with_selinux = xyes ; then
1620 if test x$have_selinux = xno ; then
1621 AC_MSG_ERROR([SELinux explicitly required, but SELinux library not found])
1625 # Check if we're building with SELinux support.
1626 if test "x$have_selinux" = xyes; then
1627 AC_DEFINE(HAVE_SELINUX, 1, [SELinux support])
1629 # See if we have the libaudit library
1630 AC_CHECK_LIB(audit, audit_log_user_avc_message,
1631 have_libaudit=yes, have_libaudit=no)
1632 if test "x$have_libaudit" = xyes; then
1633 AC_DEFINE(HAVE_LIBAUDIT, 1, [SELinux libaudit support])
1635 AC_SUBST(have_libaudit)
1637 # See if we have the libcap library
1638 AC_CHECK_LIB(cap, cap_init, have_libcap=yes, have_libcap=no)
1639 if test "x$have_libcap" = xyes; then
1640 AC_DEFINE(HAVE_LIBCAP, 1, [SELinux libcap support])
1642 AC_SUBST(have_libcap)
1644 AC_SUBST(have_selinux)
1647 dnl Check for silly hacked compilers predefining _FORTIFY_SOURCE.
1648 dnl Since we are building the implementations of the fortified functions here,
1649 dnl having the macro defined interacts very badly.
1650 dnl _FORTIFY_SOURCE requires compiler optimization level 1 (gcc -O1)
1651 dnl and above (see "man FEATURE_TEST_MACROS").
1652 dnl So do NOT replace AC_COMPILE_IFELSE with AC_PREPROC_IFELSE.
1653 AC_CACHE_CHECK([for _FORTIFY_SOURCE predefine], libc_cv_predef_fortify_source,
1654 [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[
1655 #ifdef _FORTIFY_SOURCE
1658 [libc_cv_predef_fortify_source=no],
1659 [libc_cv_predef_fortify_source=yes])])
1660 if test $libc_cv_predef_fortify_source = yes; then
1661 CPPUNDEFS="${CPPUNDEFS:+$CPPUNDEFS }-U_FORTIFY_SOURCE"
1665 # Some linkers on some architectures support __ehdr_start but with
1666 # bugs. Make sure usage of it does not create relocations in the
1667 # output (as the linker should resolve them all for us).
1668 AC_CACHE_CHECK([whether the linker provides working __ehdr_start],
1669 libc_cv_ehdr_start, [
1670 old_CFLAGS="$CFLAGS"
1671 old_LDFLAGS="$LDFLAGS"
1673 CFLAGS="$CFLAGS -fPIC"
1674 LDFLAGS="$LDFLAGS -nostdlib -nostartfiles -shared $no_ssp"
1676 AC_LINK_IFELSE([AC_LANG_SOURCE([
1681 extern const Ehdr __ehdr_start __attribute__ ((visibility ("hidden")));
1682 long ehdr (void) { return __ehdr_start.val; }
1684 [if $READELF -r conftest | grep -F __ehdr_start >/dev/null; then
1685 libc_cv_ehdr_start=broken
1687 libc_cv_ehdr_start=yes
1688 fi], [libc_cv_ehdr_start=no])
1689 CFLAGS="$old_CFLAGS"
1690 LDFLAGS="$old_LDFLAGS"
1693 if test "$libc_cv_ehdr_start" = yes; then
1694 AC_DEFINE([HAVE_EHDR_START])
1695 elif test "$libc_cv_ehdr_start" = broken; then
1696 AC_MSG_WARN([linker is broken -- you should upgrade])
1699 dnl Starting with binutils 2.35, GAS can attach multiple symbol versions
1700 dnl to one symbol (PR 23840).
1701 AC_CACHE_CHECK(whether the assembler requires one version per symbol,
1702 libc_cv_symver_needs_alias, [dnl
1703 cat > conftest.s <<EOF
1707 .symver testfunc, testfunc1@VERSION1
1708 .symver testfunc, testfunc1@VERSION2
1710 libc_cv_symver_needs_alias=no
1711 if ${CC-cc} $ASFLAGS -c conftest.s 2>&AS_MESSAGE_LOG_FD; then
1712 libc_cv_symver_needs_alias=no
1714 libc_cv_symver_needs_alias=yes
1718 if test "$libc_cv_symver_needs_alias" = yes; then
1719 AC_DEFINE(SYMVER_NEEDS_ALIAS)
1722 AC_CACHE_CHECK(for __builtin_trap with no external dependencies,
1723 libc_cv_builtin_trap, [dnl
1724 libc_cv_builtin_trap=no
1725 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[__builtin_trap ()]])],[
1726 libc_undefs=`$NM -u conftest.o |
1727 LC_ALL=C $AWK '$1 == "U" { print $2 | "sort -u"; next } { exit(1) }' \
1728 2>&AS_MESSAGE_LOG_FD` || {
1729 AC_MSG_ERROR([confusing output from $NM -u])
1731 echo >&AS_MESSAGE_LOG_FD "libc_undefs='$libc_undefs'"
1732 if test -z "$libc_undefs"; then
1733 libc_cv_builtin_trap=yes
1735 if test $libc_cv_builtin_trap = yes; then
1736 AC_DEFINE([HAVE_BUILTIN_TRAP])
1739 dnl C++ feature tests.
1742 AC_CACHE_CHECK([whether the C++ compiler supports thread_local],
1743 libc_cv_cxx_thread_local, [
1744 old_CXXFLAGS="$CXXFLAGS"
1745 CXXFLAGS="$CXXFLAGS -std=gnu++11"
1746 AC_COMPILE_IFELSE([AC_LANG_SOURCE([
1749 // Compiler support.
1756 S * get () { return &s; }
1758 // libstdc++ support.
1759 #ifndef _GLIBCXX_HAVE___CXA_THREAD_ATEXIT_IMPL
1760 #error __cxa_thread_atexit_impl not supported
1763 [libc_cv_cxx_thread_local=yes],
1764 [libc_cv_cxx_thread_local=no])
1765 CXXFLAGS="$old_CXXFLAGS"
1767 AC_SUBST(libc_cv_cxx_thread_local)
1770 dnl End of C++ feature tests.
1772 ### End of automated tests.
1773 ### Now run sysdeps configure fragments.
1775 # They also can set these variables.
1777 ldd_rewrite_script=no
1778 libc_cv_sysconfdir=$sysconfdir
1779 libc_cv_localstatedir=$localstatedir
1780 libc_cv_gcc_unwind_find_fde=no
1784 # Iterate over all the sysdep directories we will use, running their
1785 # configure fragments.
1786 for dir in $sysnames; do
1789 *) dest=$srcdir/$dir ;;
1791 if test -r $dest/configure; then
1792 AC_MSG_RESULT(running configure fragment for $dir)
1797 if test x"$build_mathvec" = xnotset; then
1800 LIBC_CONFIG_VAR([build-mathvec], [$build_mathvec])
1802 AC_SUBST(libc_extra_cflags)
1803 AC_SUBST(libc_extra_cppflags)
1805 if test x$libc_cv_gcc_unwind_find_fde = xyes; then
1806 AC_DEFINE(EXPORT_UNWIND_FIND_FDE)
1808 AC_SUBST(libc_cv_gcc_unwind_find_fde)
1810 # A sysdeps configure fragment can reset this if IFUNC is not actually
1811 # usable even though the assembler knows how to generate the symbol type.
1812 if test x"$libc_cv_ld_gnu_indirect_function" = xyes; then
1813 AC_DEFINE(HAVE_IFUNC)
1815 LIBC_CONFIG_VAR([have-ifunc], [$libc_cv_ld_gnu_indirect_function])
1817 if test x"$libc_cv_gcc_indirect_function" = xyes; then
1818 AC_DEFINE(HAVE_GCC_IFUNC)
1820 LIBC_CONFIG_VAR([have-gcc-ifunc], [$libc_cv_gcc_indirect_function])
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 # Check target support for static PIE
1883 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#ifndef SUPPORT_STATIC_PIE
1884 # error static PIE is not supported
1885 #endif]])], , AC_MSG_ERROR([the architecture does not support static PIE]))
1886 # The linker must support --no-dynamic-linker.
1887 if test "$libc_cv_no_dynamic_linker" != yes; then
1888 AC_MSG_ERROR([linker support for --no-dynamic-linker needed])
1891 libc_cv_pie_default=yes
1892 AC_DEFINE(ENABLE_STATIC_PIE)
1894 LIBC_CONFIG_VAR([enable-static-pie], [$static_pie])
1897 AC_SUBST(static_nss)
1901 dnl See sysdeps/mach/configure.ac for this variable.
1902 AC_SUBST(mach_interface_list)
1904 VERSION=`sed -n -e 's/^#define VERSION "\([^"]*\)"/\1/p' < $srcdir/version.h`
1905 RELEASE=`sed -n -e 's/^#define RELEASE "\([^"]*\)"/\1/p' < $srcdir/version.h`
1909 if test "$pthread_in_libc" = yes; then
1910 AC_DEFINE(PTHREAD_IN_LIBC)
1912 AC_SUBST(pthread_in_libc)
1914 AC_CONFIG_FILES([config.make Makefile])
1915 AC_CONFIG_COMMANDS([default],[[
1916 case $CONFIG_FILES in *config.make*)
1917 echo "$config_vars" >> config.make;;
1919 test -d bits || mkdir bits]],[[config_vars='$config_vars']])