1 dnl Process this file with autoconf to produce a configure script.
2 dnl Note we do not use AC_PREREQ here! See aclocal.m4 for what we use instead.
3 AC_INIT([GNU C Library], [(see version.h)], [https://sourceware.org/bugzilla/], [glibc])
4 AC_CONFIG_SRCDIR([include/features.h])
5 AC_CONFIG_HEADERS([config.h])
6 AC_CONFIG_AUX_DIR([scripts])
8 ACX_PKGVERSION([GNU libc])
9 ACX_BUGURL([http://www.gnu.org/software/libc/bugs.html])
10 AC_DEFINE_UNQUOTED([PKGVERSION], ["$PKGVERSION"],
11 [Package description])
12 AC_DEFINE_UNQUOTED([REPORT_BUGS_TO], ["$REPORT_BUGS_TO"],
13 [Bug reporting address])
15 # Glibc should not depend on any header files
16 AC_DEFUN([_AC_INCLUDES_DEFAULT_REQUIREMENTS],
17 [m4_divert_text([DEFAULTS],
18 [ac_includes_default='/* none */'])])
20 # We require GCC, and by default use its preprocessor. Override AC_PROG_CPP
21 # here to work around the Autoconf issue discussed in
22 # <https://sourceware.org/ml/libc-alpha/2013-01/msg00721.html>.
23 AC_DEFUN([AC_PROG_CPP],
24 [AC_REQUIRE([AC_PROG_CC])dnl
25 AC_ARG_VAR([CPP], [C preprocessor])dnl
26 _AC_ARG_VAR_CPPFLAGS()dnl
27 # On Suns, sometimes $CPP names a directory.
28 if test -n "$CPP" && test -d "$CPP"; then
31 if test -z "$CPP"; then
37 # We require GCC. Override _AC_PROG_CC_C89 here to work around the Autoconf
39 # <https://sourceware.org/ml/libc-alpha/2013-01/msg00757.html>.
40 AC_DEFUN([_AC_PROG_CC_C89], [[$1]])
42 dnl This is here so we can set $subdirs directly based on configure fragments.
48 if test $host != $build; then
49 AC_CHECK_PROGS(BUILD_CC, gcc cc)
51 AC_SUBST(cross_compiling)
53 AC_CHECK_TOOL(READELF, readelf, false)
55 # We need the C++ compiler only for testing.
57 # It's useless to us if it can't link programs (e.g. missing -lstdc++).
58 AC_CACHE_CHECK([whether $CXX can link programs], libc_cv_cxx_link_ok, [dnl
60 # Default, dynamic case.
61 AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
62 [libc_cv_cxx_link_ok=yes],
63 [libc_cv_cxx_link_ok=no])
65 old_LDFLAGS="$LDFLAGS"
66 LDFLAGS="$LDFLAGS -static"
67 AC_LINK_IFELSE([AC_LANG_SOURCE([
73 std::cout << "Hello, world!";
78 [libc_cv_cxx_link_ok=no])
79 LDFLAGS="$old_LDFLAGS"
81 AS_IF([test $libc_cv_cxx_link_ok != yes], [CXX=])
83 if test "`cd $srcdir; pwd -P`" = "`pwd -P`"; then
84 AC_MSG_ERROR([you must configure in a separate build directory])
87 # This will get text that should go into config.make.
90 # Check for a --with-gd argument and set libgd-LDFLAGS in config.make.
92 AC_HELP_STRING([--with-gd=DIR],
93 [find libgd include dir and library with prefix DIR]),
97 *) libgd_include="-I$withval/include"
98 libgd_ldflags="-L$withval/lib" ;;
101 AC_ARG_WITH([gd-include],
102 AC_HELP_STRING([--with-gd-include=DIR],
103 [find libgd include files in DIR]),
105 case "$with_gd_include" in
107 *) libgd_include="-I$withval" ;;
110 AC_ARG_WITH([gd-lib],
111 AC_HELP_STRING([--with-gd-lib=DIR],
112 [find libgd library files in DIR]),
114 case "$with_gd_lib" in
116 *) libgd_ldflags="-L$withval" ;;
120 if test -n "$libgd_include"; then
121 config_vars="$config_vars
122 CFLAGS-memusagestat.c = $libgd_include"
124 if test -n "$libgd_ldflags"; then
125 config_vars="$config_vars
126 libgd-LDFLAGS = $libgd_ldflags"
129 dnl Arguments to specify presence of other packages/features.
130 AC_ARG_WITH([binutils],
131 AC_HELP_STRING([--with-binutils=PATH],
132 [specify location of binutils (as and ld)]),
133 [path_binutils=$withval],
135 AC_ARG_WITH([selinux],
136 AC_HELP_STRING([--with-selinux],
137 [if building with SELinux support]),
138 [with_selinux=$withval],
141 AC_ARG_WITH([headers],
142 AC_HELP_STRING([--with-headers=PATH],
143 [location of system headers to use
144 (for example /usr/src/linux/include)
145 @<:@default=compiler default@:>@]),
146 [sysheaders=$withval],
150 AC_SUBST(use_default_link)
151 AC_ARG_WITH([default-link],
152 AC_HELP_STRING([--with-default-link],
153 [do not use explicit linker scripts]),
154 [use_default_link=$withval],
155 [use_default_link=default])
157 dnl Additional build flags injection.
158 AC_ARG_WITH([nonshared-cflags],
159 AC_HELP_STRING([--with-nonshared-cflags=CFLAGS],
160 [build nonshared libraries with additional CFLAGS]),
161 [extra_nonshared_cflags=$withval],
162 [extra_nonshared_cflags=])
163 AC_SUBST(extra_nonshared_cflags)
165 AC_ARG_ENABLE([sanity-checks],
166 AC_HELP_STRING([--disable-sanity-checks],
167 [really do not use threads (should not be used except in special situations) @<:@default=yes@:>@]),
168 [enable_sanity=$enableval],
171 AC_ARG_ENABLE([shared],
172 AC_HELP_STRING([--enable-shared],
173 [build shared library @<:@default=yes if GNU ld@:>@]),
176 AC_ARG_ENABLE([profile],
177 AC_HELP_STRING([--enable-profile],
178 [build profiled library @<:@default=no@:>@]),
179 [profile=$enableval],
181 AC_ARG_ENABLE([static-pie],
182 AC_HELP_STRING([--enable-static-pie],
183 [enable static PIE support and use it in the testsuite @<:@default=no@:>@]),
184 [static_pie=$enableval],
186 AC_ARG_ENABLE([timezone-tools],
187 AC_HELP_STRING([--disable-timezone-tools],
188 [do not install timezone tools @<:@default=install@:>@]),
189 [enable_timezone_tools=$enableval],
190 [enable_timezone_tools=yes])
191 AC_SUBST(enable_timezone_tools)
193 AC_ARG_ENABLE([hardcoded-path-in-tests],
194 AC_HELP_STRING([--enable-hardcoded-path-in-tests],
195 [hardcode newly built glibc path in tests @<:@default=no@:>@]),
196 [hardcoded_path_in_tests=$enableval],
197 [hardcoded_path_in_tests=no])
198 AC_SUBST(hardcoded_path_in_tests)
200 AC_ARG_ENABLE([stackguard-randomization],
201 AC_HELP_STRING([--enable-stackguard-randomization],
202 [initialize __stack_chk_guard canary with a random number at program start]),
203 [enable_stackguard_randomize=$enableval],
204 [enable_stackguard_randomize=no])
205 if test "$enable_stackguard_randomize" = yes; then
206 AC_DEFINE(ENABLE_STACKGUARD_RANDOMIZE)
209 AC_ARG_ENABLE([hidden-plt],
210 AC_HELP_STRING([--disable-hidden-plt],
211 [do not hide internal function calls to avoid PLT]),
214 if test "x$hidden" = xno; then
218 AC_ARG_ENABLE([bind-now],
219 AC_HELP_STRING([--enable-bind-now],
220 [disable lazy relocations in DSOs]),
221 [bindnow=$enableval],
224 if test "x$bindnow" = xyes; then
228 dnl Build glibc with -fstack-protector, -fstack-protector-all, or
229 dnl -fstack-protector-strong.
230 AC_ARG_ENABLE([stack-protector],
231 AC_HELP_STRING([--enable-stack-protector=@<:@yes|no|all|strong@:>@],
232 [Use -fstack-protector[-all|-strong] to detect glibc buffer overflows]),
233 [enable_stack_protector=$enableval],
234 [enable_stack_protector=no])
235 case "$enable_stack_protector" in
236 all|yes|no|strong) ;;
237 *) AC_MSG_ERROR([Not a valid argument for --enable-stack-protector: \"$enable_stack_protector\"]);;
240 dnl On some platforms we cannot use dynamic loading. We must provide
241 dnl static NSS modules.
242 AC_ARG_ENABLE([static-nss],
243 AC_HELP_STRING([--enable-static-nss],
244 [build static NSS modules @<:@default=no@:>@]),
245 [static_nss=$enableval],
247 dnl Enable static NSS also if we build no shared objects.
248 if test x"$static_nss" = xyes || test x"$shared" = xno; then
250 AC_DEFINE(DO_STATIC_NSS)
253 AC_ARG_ENABLE([force-install],
254 AC_HELP_STRING([--disable-force-install],
255 [don't force installation of files from this package, even if they are older than the installed files]),
256 [force_install=$enableval],
258 AC_SUBST(force_install)
260 AC_ARG_ENABLE([maintainer-mode],
261 AC_HELP_STRING([--enable-maintainer-mode],
262 [enable make rules and dependencies not useful (and sometimes confusing) to the casual installer]),
263 [maintainer=$enableval],
266 dnl On some platforms we allow dropping compatibility with all kernel
268 AC_ARG_ENABLE([kernel],
269 AC_HELP_STRING([--enable-kernel=VERSION],
270 [compile for compatibility with kernel not older than VERSION]),
271 [minimum_kernel=$enableval],
273 dnl Prevent unreasonable values.
274 if test "$minimum_kernel" = yes || test "$minimum_kernel" = no; then
275 # Better nothing than this.
278 if test "$minimum_kernel" = current; then
279 minimum_kernel=`uname -r 2>/dev/null` || minimum_kernel=
283 dnl For the development we sometimes want gcc to issue even more warnings.
284 dnl This is not the default since many of the extra warnings are not
286 AC_ARG_ENABLE([all-warnings],
287 AC_HELP_STRING([--enable-all-warnings],
288 [enable all useful warnings gcc can issue]),
289 [all_warnings=$enableval],
291 AC_SUBST(all_warnings)
293 AC_ARG_ENABLE([werror],
294 AC_HELP_STRING([--disable-werror],
295 [do not build with -Werror]),
296 [enable_werror=$enableval],
298 AC_SUBST(enable_werror)
300 AC_ARG_ENABLE([multi-arch],
301 AC_HELP_STRING([--enable-multi-arch],
302 [enable single DSO with optimizations for multiple architectures]),
303 [multi_arch=$enableval],
304 [multi_arch=default])
306 AC_ARG_ENABLE([experimental-malloc],
307 AC_HELP_STRING([--disable-experimental-malloc],
308 [disable experimental malloc features]),
309 [experimental_malloc=$enableval],
310 [experimental_malloc=yes])
311 AC_SUBST(experimental_malloc)
313 AC_ARG_ENABLE([crypt],
314 AC_HELP_STRING([--disable-crypt],
315 [do not build nor install the passphrase hashing library, libcrypt]),
316 [build_crypt=$enableval],
318 AC_SUBST(build_crypt)
320 AC_ARG_ENABLE([nss-crypt],
321 AC_HELP_STRING([--enable-nss-crypt],
322 [enable libcrypt to use nss]),
323 [nss_crypt=$enableval],
325 if test x$build_libcrypt = xno && test x$nss_crypt = xyes; then
326 AC_MSG_WARN([--enable-nss-crypt has no effect when libcrypt is disabled])
329 if test x$nss_crypt = xyes; then
330 nss_includes=-I$(nss-config --includedir 2>/dev/null)
331 if test $? -ne 0; then
332 AC_MSG_ERROR([cannot find include directory with nss-config])
334 nspr_includes=-I$(nspr-config --includedir 2>/dev/null)
335 if test $? -ne 0; then
336 AC_MSG_ERROR([cannot find include directory with nspr-config])
339 CFLAGS="$CFLAGS $nss_includes $nspr_includes"
340 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
342 #include <nsslowhash.h>
343 void f (void) { NSSLOW_Init (); }])],
344 libc_cv_nss_crypt=yes,
346 cannot find NSS headers with lowlevel hash function interfaces]))
348 old_LDFLAGS="$LDFLAGS"
349 LIBS="$LIBS -lfreebl3"
350 AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
352 #include <nsslowhash.h>],
354 libc_cv_nss_crypt=yes,
356 cannot link program using lowlevel NSS hash functions]))
357 # Check to see if there is a static NSS cryptographic library.
358 # If there isn't then we can't link anything with libcrypt.a,
359 # and that might mean disabling some static tests.
360 LDFLAGS="$LDFLAGS -static"
361 AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
363 #include <nsslowhash.h>],
365 libc_cv_static_nss_crypt=yes,
366 libc_cv_static_nss_crypt=no)
367 LDFLAGS="$old_LDFLAGS"
372 libc_cv_static_nss_crypt=no
374 AC_SUBST(libc_cv_nss_crypt)
375 AC_SUBST(libc_cv_static_nss_crypt)
378 AC_ARG_ENABLE([obsolete-rpc],
379 AC_HELP_STRING([--enable-obsolete-rpc],
380 [build and install the obsolete RPC code for link-time usage]),
381 [link_obsolete_rpc=$enableval],
382 [link_obsolete_rpc=no])
383 AC_SUBST(link_obsolete_rpc)
385 if test "$link_obsolete_rpc" = yes; then
386 AC_DEFINE(LINK_OBSOLETE_RPC)
389 AC_ARG_ENABLE([obsolete-nsl],
390 AC_HELP_STRING([--enable-obsolete-nsl],
391 [build and install the obsolete libnsl library and depending NSS modules]),
392 [build_obsolete_nsl=$enableval],
393 [build_obsolete_nsl=no])
394 AC_SUBST(build_obsolete_nsl)
396 if test "$build_obsolete_nsl" = yes; then
397 AC_DEFINE(LINK_OBSOLETE_NSL)
400 AC_ARG_ENABLE([systemtap],
401 [AS_HELP_STRING([--enable-systemtap],
402 [enable systemtap static probe points @<:@default=no@:>@])],
403 [systemtap=$enableval],
405 if test "x$systemtap" != xno; then
406 AC_CACHE_CHECK([for systemtap static probe support], libc_cv_sdt, [dnl
408 CFLAGS="-std=gnu11 $CFLAGS"
409 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <sys/sdt.h>
410 void foo (int i, void *p)
412 asm ("" STAP_PROBE_ASM (foo, bar, STAP_PROBE_ASM_TEMPLATE (2)) ""
413 :: STAP_PROBE_ASM_OPERANDS (2, i, p));
414 }]])], [libc_cv_sdt=yes], [libc_cv_sdt=no])
415 CFLAGS="$old_CFLAGS"])
416 if test $libc_cv_sdt = yes; then
417 AC_DEFINE([USE_STAP_PROBE])
418 elif test "x$systemtap" != xauto; then
419 AC_MSG_FAILURE([systemtap support needs sys/sdt.h with asm support])
423 AC_ARG_ENABLE([build-nscd],
424 [AS_HELP_STRING([--disable-build-nscd],
425 [disable building and installing the nscd daemon])],
426 [build_nscd=$enableval],
427 [build_nscd=default])
430 # Note the use of $use_nscd is near the bottom of the file.
431 AC_ARG_ENABLE([nscd],
432 [AS_HELP_STRING([--disable-nscd],
433 [library functions will not contact the nscd daemon])],
434 [use_nscd=$enableval],
437 AC_ARG_ENABLE([pt_chown],
438 [AS_HELP_STRING([--enable-pt_chown],
439 [Enable building and installing pt_chown])],
440 [build_pt_chown=$enableval],
442 AC_SUBST(build_pt_chown)
443 if test "$build_pt_chown" = yes; then
444 AC_DEFINE(HAVE_PT_CHOWN)
447 AC_ARG_ENABLE([tunables],
448 [AS_HELP_STRING([--enable-tunables],
449 [Enable tunables support. Known values are 'yes', 'no' and 'valstring'])],
450 [have_tunables=$enableval],
452 AC_SUBST(have_tunables)
453 if test "$have_tunables" = yes; then
454 AC_DEFINE(HAVE_TUNABLES)
457 # The abi-tags file uses a fairly simplistic model for name recognition that
458 # can't distinguish i486-pc-linux-gnu fully from i486-pc-gnu. So we mutate a
459 # $host_os of `gnu*' here to be `gnu-gnu*' just so that it can tell.
460 # This doesn't get used much beyond that, so it's fairly safe.
465 host_os=`echo $host_os | sed -e 's/gnu/gnu-gnu/'`
469 AC_ARG_ENABLE([mathvec],
470 [AS_HELP_STRING([--enable-mathvec],
471 [Enable building and installing mathvec @<:@default depends on architecture@:>@])],
472 [build_mathvec=$enableval],
473 [build_mathvec=notset])
476 AC_HELP_STRING([--enable-cet],
477 [enable Intel Control-flow Enforcement Technology (CET), x86 only]),
478 [enable_cet=$enableval],
481 # We keep the original values in `$config_*' and never modify them, so we
482 # can write them unchanged into config.make. Everything else uses
483 # $machine, $vendor, and $os, and changes them whenever convenient.
484 config_machine=$host_cpu config_vendor=$host_vendor config_os=$host_os
486 # Don't allow vendor == "unknown"
487 test "$config_vendor" = unknown && config_vendor=
488 config_os="`echo $config_os | sed 's/^unknown-//'`"
490 # Some configurations imply other options.
493 # The configure fragment of a port can modify these to supplement
494 # or override the table in the case statement below. No fragment should
495 # ever change the config_* variables, however.
496 machine=$config_machine
497 vendor=$config_vendor
503 AS_HELP_STRING([--with-cpu=CPU], [select code for CPU variant]),
506 yes|'') AC_MSG_ERROR([--with-cpu requires an argument]) ;;
508 *) submachine="$withval" ;;
512 # An preconfigure script can set this when it wants to disable the sanity
516 # A preconfigure script for a system that may or may not use fpu
517 # sysdeps directories sets this to a preprocessor conditional for
518 # whether to use such directories.
521 dnl Let sysdeps/*/preconfigure act here.
522 LIBC_PRECONFIGURE([$srcdir], [for sysdeps])
526 ### By using the undocumented --enable-hacker-mode option for configure
527 ### one can skip this test to make the configuration not fail for unsupported
530 if test -z "$enable_hacker_mode" && test x"$libc_config_ok" != xyes; then
531 case "$machine-$host_os" in
536 *** The GNU C library is currently unavailable for this platform.
537 *** If you are interested in seeing glibc on this platform visit
538 *** the "How to submit a new port" in the wiki:
539 *** https://sourceware.org/glibc/wiki/#Development
540 *** and join the community!])
545 # Set base_machine if not set by a preconfigure fragment.
546 test -n "$base_machine" || base_machine=$machine
547 AC_SUBST(base_machine)
549 # Determine whether to use fpu or nofpu sysdeps directories.
550 AC_CACHE_CHECK([for use of fpu sysdeps directories],
551 libc_cv_with_fp, [dnl
552 cat > conftest.c <<EOF
556 # error "no hardware floating point"
560 if ${CC-cc} $CFLAGS $CPPFLAGS -S conftest.c -o conftest.s \
561 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
565 AC_SUBST(libc_cv_with_fp)
567 AC_CACHE_CHECK(for -fstack-protector, libc_cv_ssp, [dnl
568 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector],
573 AC_CACHE_CHECK(for -fstack-protector-strong, libc_cv_ssp_strong, [dnl
574 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-strong],
575 [libc_cv_ssp_strong=yes],
576 [libc_cv_ssp_strong=no])
579 AC_CACHE_CHECK(for -fstack-protector-all, libc_cv_ssp_all, [dnl
580 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-all],
581 [libc_cv_ssp_all=yes],
582 [libc_cv_ssp_all=no])
587 if test "$libc_cv_ssp" = yes; then
588 no_stack_protector="-fno-stack-protector -DSTACK_PROTECTOR_LEVEL=0"
589 AC_DEFINE(HAVE_CC_NO_STACK_PROTECTOR)
592 if test "$enable_stack_protector" = yes && test "$libc_cv_ssp" = yes; then
593 stack_protector="-fstack-protector"
594 AC_DEFINE(STACK_PROTECTOR_LEVEL, 1)
595 elif test "$enable_stack_protector" = all && test "$libc_cv_ssp_all" = yes; then
596 stack_protector="-fstack-protector-all"
597 AC_DEFINE(STACK_PROTECTOR_LEVEL, 2)
598 elif test "$enable_stack_protector" = strong && test "$libc_cv_ssp_strong" = yes; then
599 stack_protector="-fstack-protector-strong"
600 AC_DEFINE(STACK_PROTECTOR_LEVEL, 3)
602 stack_protector="-fno-stack-protector"
603 AC_DEFINE(STACK_PROTECTOR_LEVEL, 0)
605 AC_SUBST(libc_cv_ssp)
606 AC_SUBST(stack_protector)
607 AC_SUBST(no_stack_protector)
609 if test -n "$stack_protector"; then
610 dnl Don't run configure tests with stack-protection on, to avoid problems with
612 no_ssp=-fno-stack-protector
616 if test "$enable_stack_protector" != no; then
617 AC_MSG_ERROR([--enable-stack-protector=$enable_stack_protector specified, but specified level of stack protection is not supported by the compiler.])
621 # For the multi-arch option we need support in the assembler & linker.
622 AC_CACHE_CHECK([for assembler and linker STT_GNU_IFUNC support],
623 libc_cv_ld_gnu_indirect_function, [dnl
624 cat > conftest.S <<EOF
625 .type foo,%gnu_indirect_function
638 libc_cv_ld_gnu_indirect_function=no
639 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
640 -nostartfiles -nostdlib $no_ssp \
641 -o conftest conftest.S 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
642 # Do a link to see if the backend supports IFUNC relocs.
643 $READELF -r conftest 1>&AS_MESSAGE_LOG_FD
644 LC_ALL=C $READELF -r conftest | grep 'no relocations' >/dev/null || {
645 libc_cv_ld_gnu_indirect_function=yes
650 # Check if gcc supports attribute ifunc as it is used in libc_ifunc macro.
651 AC_CACHE_CHECK([for gcc attribute ifunc support],
652 libc_cv_gcc_indirect_function, [dnl
653 cat > conftest.c <<EOF
654 extern int func (int);
655 int used_func (int a)
659 static void *resolver ()
663 extern __typeof (func) func __attribute__ ((ifunc ("resolver")));
665 libc_cv_gcc_indirect_function=no
666 if ${CC-cc} -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD \
667 2>&AS_MESSAGE_LOG_FD ; then
668 if $READELF -s conftest.o | grep IFUNC >/dev/null 2>&AS_MESSAGE_LOG_FD; then
669 libc_cv_gcc_indirect_function=yes
674 # Check if linker supports textrel relocation with ifunc (used on elf/tests).
675 # Note that it relies on libc_cv_ld_gnu_indirect_function test above.
676 AC_CACHE_CHECK([whether the linker supports textrels along with ifunc],
677 libc_cv_textrel_ifunc, [dnl
678 cat > conftest.S <<EOF
679 .type foo,%gnu_indirect_function
700 libc_cv_textrel_ifunc=no
701 if test $libc_cv_ld_gnu_indirect_function = yes; then
702 if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp -pie -o conftest conftest.S); then
703 libc_cv_textrel_ifunc=yes
707 AC_SUBST(libc_cv_textrel_ifunc)
709 # Check if gcc warns about alias for function with incompatible types.
710 AC_CACHE_CHECK([if compiler warns about alias for function with incompatible types],
711 libc_cv_gcc_incompatible_alias, [dnl
712 cat > conftest.c <<EOF
713 int __redirect_foo (const void *s, int c);
715 __typeof (__redirect_foo) *foo_impl (void) __asm__ ("foo");
716 __typeof (__redirect_foo) *foo_impl (void)
721 extern __typeof (__redirect_foo) foo_alias __attribute__ ((alias ("foo")));
723 libc_cv_gcc_incompatible_alias=yes
724 if ${CC-cc} -Werror -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
725 libc_cv_gcc_incompatible_alias=no
729 if test x"$libc_cv_ld_gnu_indirect_function" != xyes; then
730 if test x"$multi_arch" = xyes; then
731 AC_MSG_ERROR([--enable-multi-arch support requires assembler and linker support])
736 if test x"$libc_cv_gcc_indirect_function" != xyes; then
737 # GCC 8+ emits a warning for alias with incompatible types and it might
738 # fail to build ifunc resolvers aliases to either weak or internal
739 # symbols. Disables multiarch build in this case.
740 if test x"$libc_cv_gcc_incompatible_alias" == xyes; then
741 AC_MSG_WARN([gcc emits a warning for alias between functions of incompatible types])
742 if test x"$multi_arch" = xyes; then
743 AC_MSG_ERROR([--enable-multi-arch support requires a gcc with gnu-indirect-function support])
745 AC_MSG_WARN([Multi-arch is disabled.])
747 elif test x"$multi_arch" = xyes; then
748 AC_MSG_WARN([--enable-multi-arch support recommends a gcc with gnu-indirect-function support.
749 Please use a gcc which supports it by default or configure gcc with --enable-gnu-indirect-function])
753 if test x"$multi_arch" != xno; then
754 multi_arch_d=/multiarch
757 # Compute the list of sysdep directories for this configuration.
758 # This can take a while to compute.
759 sysdep_dir=$srcdir/sysdeps
760 AC_MSG_CHECKING(sysdep dirs)
761 dnl We need to use [ and ] for other purposes for a while now.
763 # Make sco3.2v4 become sco3.2.4 and sunos4.1.1_U1 become sunos4.1.1.U1.
764 os="`echo $os | sed 's/\([0-9A-Z]\)[v_]\([0-9A-Z]\)/\1.\2/g'`"
766 test "x$base_os" != x || case "$os" in
773 # For sunos4.1.1, try sunos4.1.1, then sunos4.1, then sunos4, then sunos.
776 while o=`echo $tail | sed 's/\.[^.]*$//'`; test $o != $tail; do
780 o=`echo $tail | sed 's/[0-9]*$//'`
781 if test $o != $tail; then
784 # For linux-gnu, try linux-gnu, then linux.
785 o=`echo $tail | sed 's/-.*$//'`
786 if test $o != $tail; then
790 # For unix/sysv/sysv4, try unix/sysv/sysv4, then unix/sysv, then unix.
793 while b=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$b"; do
799 # For sparc/sparc32, try sparc/sparc32 and then sparc.
801 tail=$machine${submachine:+/$submachine}
802 while m=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$m"; do
804 # Prepend the machine's FPU directory unless --without-fp.
805 if test "$libc_cv_with_fp" = yes; then
810 # For each machine term, try it with and then without /multiarch.
811 for try_fpu in $maybe_fpu ''; do
812 for try_multi in $multi_arch_d ''; do
813 mach="$mach /$1$try_fpu$try_multi"
819 dnl We are done with glob and regexp uses of [ and ]; return to autoconf.
822 # Find what sysdep directories exist.
824 for b in $base ''; do
825 for m0 in $mach ''; do
826 for v in /$vendor ''; do
827 test "$v" = / && continue
828 for o in /$ostry ''; do
829 test "$o" = / && continue
830 for m in $mach ''; do
831 try_suffix="$m0$b$v$o$m"
832 if test -n "$try_suffix"; then
833 try_srcdir="${srcdir}/"
834 try="sysdeps$try_suffix"
835 test -n "$enable_debug_configure" &&
836 echo "$0 [DEBUG]: try $try" >&2
837 if test -d "$try_srcdir$try"; then
838 sysnames="$sysnames $try"
839 { test -n "$o" || test -n "$b"; } && os_used=t
840 { test -n "$m" || test -n "$m0"; } && machine_used=t
842 x*/$submachine) submachine_used=t ;;
852 # If the assembler supports gnu_indirect_function symbol type and the
853 # architecture supports multi-arch, we enable multi-arch by default.
858 test x"$multi_arch" = xdefault && multi_arch=no
861 if test x"$multi_arch" != xno; then
862 AC_DEFINE(USE_MULTIARCH)
866 if test -z "$os_used" && test "$os" != none; then
867 AC_MSG_ERROR(Operating system $os is not supported.)
869 if test -z "$machine_used" && test "$machine" != none; then
870 AC_MSG_ERROR(The $machine is not supported.)
872 if test -z "$submachine_used" && test -n "$submachine"; then
873 AC_MSG_ERROR(The $submachine subspecies of $host_cpu is not supported.)
877 # We have now validated the configuration.
879 # Expand the list of system names into a full list of directories
880 # from each element's parent name and Implies file (if present).
883 while test $# -gt 0; do
887 case " $names " in *" $name "*)
888 # Already in the list.
892 # Report each name as we discover it, so there is no long pause in output.
893 echo $ECHO_N "$name $ECHO_C" >&AS_MESSAGE_FD
895 name_base=`echo $name | sed -e 's@\(.*sysdeps\)/.*@\1@'`
899 *) xsrcdir=$srcdir/ ;;
901 test -n "$enable_debug_configure" &&
902 echo "[DEBUG]: name/Implies $xsrcdir$name/Implies" >&2
904 for implies_file in Implies Implies-before Implies-after; do
905 implies_type=`echo $implies_file | sed s/-/_/`
906 eval ${implies_type}=
907 if test -f $xsrcdir$name/$implies_file; then
908 # Collect more names from the `Implies' file (removing comments).
909 implied_candidate="`sed 's/#.*$//' < $xsrcdir$name/$implies_file`"
910 for x in $implied_candidate; do
912 if test -d $xsrcdir$name_base/$x; then
913 eval "${implies_type}=\"\$${implies_type} \$name_base/\$x\""
918 test -n "$enable_debug_configure" &&
919 echo "[DEBUG]: $name $implies_file $x try() {$try_srcdir}$try" >&2
920 if test $try != $xsrcdir$name_base/$x && test -d $try_srcdir$try;
922 eval "${implies_type}=\"\$${implies_type} \$try\""
925 if test $found = no; then
926 AC_MSG_WARN($name/$implies_file specifies nonexistent $x)
932 # Add NAME to the list of names.
935 # Find the parent of NAME, using the empty string if it has none.
937 parent="`echo $name | sed -n -e 's=/[^/]*$==' -e '/sysdeps$/q' -e p`"
940 test -n "$enable_debug_configure" &&
941 echo "[DEBUG]: $name Implies='$Implies' rest='$*' parent='$parent' \
942 Implies_before='$Implies_before' Implies_after='$Implies_after'" >&2
944 # Add the names implied by NAME, and NAME's parent (if it has one), to
945 # the list of names to be processed (the argument list). We prepend the
946 # implied names to the list and append the parent. We want implied
947 # directories to come before further directories inferred from the
948 # configuration components; this ensures that for sysv4, unix/common
949 # (implied by unix/sysv/sysv4) comes before unix/sysv (in ostry (here $*)
951 sysnames="`echo $Implies $* $Implies_before $parent $Implies_after`"
952 test -n "$sysnames" && set $sysnames
955 # Add the default directories.
956 default_sysnames="sysdeps/generic"
957 sysnames="$names $default_sysnames"
959 # The other names were emitted during the scan.
960 AC_MSG_RESULT($default_sysnames)
966 if test "$INSTALL" = "${srcdir}/scripts/install-sh -c"; then
967 # The makefiles need to use a different form to find it in $srcdir.
968 INSTALL='\$(..)./scripts/install-sh -c'
974 # Accept binutils 2.25 or newer.
975 AC_CHECK_PROG_VER(AS, $AS, --version,
976 [GNU assembler.* \([0-9]*\.[0-9.]*\)],
977 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
978 AS=: critic_missing="$critic_missing as")
980 if test -n "`$LD --version | sed -n 's/^GNU \(gold\).*$/\1/p'`"; then
981 # Accept gold 1.14 or higher
982 AC_CHECK_PROG_VER(LD, $LD, --version,
983 [GNU gold.* \([0-9][0-9]*\.[0-9.]*\)],
984 [1.1[4-9]*|1.[2-9][0-9]*|1.1[0-9][0-9]*|[2-9].*|[1-9][0-9]*],
985 LD=: critic_missing="$critic_missing GNU gold")
987 AC_CHECK_PROG_VER(LD, $LD, --version,
988 [GNU ld.* \([0-9][0-9]*\.[0-9.]*\)],
989 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
990 LD=: critic_missing="$critic_missing GNU ld")
993 # These programs are version sensitive.
995 AC_CHECK_PROG_VER(MAKE, gnumake gmake make, --version,
996 [GNU Make[^0-9]*\([0-9][0-9.]*\)],
997 [[4-9].* | [1-9][0-9]*], critic_missing="$critic_missing make")
999 AC_CHECK_PROG_VER(MSGFMT, gnumsgfmt gmsgfmt msgfmt, --version,
1000 [GNU gettext.* \([0-9]*\.[0-9.]*\)],
1001 [0.10.3[6-9]* | 0.10.[4-9][0-9]* | 0.1[1-9]* | 0.[2-9][0-9]* | [1-9].*],
1002 MSGFMT=: aux_missing="$aux_missing msgfmt")
1003 AC_CHECK_PROG_VER(MAKEINFO, makeinfo, --version,
1004 [GNU texinfo.* \([0-9][0-9.]*\)],
1005 [4.[7-9]*|4.[1-9][0-9]*|[5-9].*],
1006 MAKEINFO=: aux_missing="$aux_missing makeinfo")
1007 AC_CHECK_PROG_VER(SED, sed, --version,
1008 [GNU sed[^0-9]* \([0-9]*\.[0-9.]*\)],
1009 [3.0[2-9]*|3.[1-9]*|[4-9]*],
1010 SED=: aux_missing="$aux_missing sed")
1011 AC_CHECK_PROG_VER(AWK, gawk, --version,
1012 [GNU Awk[^0-9]*\([0-9][0-9.]*\)],
1013 [3.1.[2-9]*|3.[2-9]*|[4-9]*], critic_missing="$critic_missing gawk")
1014 AC_CHECK_PROG_VER(BISON, bison, --version,
1015 [bison (GNU Bison) \([0-9]*\.[0-9.]*\)],
1016 [2.7*|[3-9].*|[1-9][0-9]*], critic_missing="$critic_missing bison")
1018 AC_CACHE_CHECK([if $CC is sufficient to build libc], libc_cv_compiler_ok, [
1019 AC_TRY_COMPILE([], [
1020 #if !defined __GNUC__ || __GNUC__ < 6 || (__GNUC__ == 6 && __GNUC_MINOR__ < 2)
1021 #error insufficient compiler
1023 [libc_cv_compiler_ok=yes],
1024 [libc_cv_compiler_ok=no])])
1025 AS_IF([test $libc_cv_compiler_ok != yes],
1026 [critic_missing="$critic_missing compiler"])
1028 AC_CHECK_TOOL(NM, nm, false)
1030 if test "x$maintainer" = "xyes"; then
1031 AC_CHECK_PROGS(AUTOCONF, autoconf, no)
1032 case "x$AUTOCONF" in
1033 xno|x|x:) AUTOCONF=no ;;
1036 whether $AUTOCONF${ACFLAGS:+ }$ACFLAGS works, libc_cv_autoconf_works, [dnl
1037 if (cd $srcdir; $AUTOCONF $ACFLAGS configure.ac > /dev/null 2>&1); then
1038 libc_cv_autoconf_works=yes
1040 libc_cv_autoconf_works=no
1042 test $libc_cv_autoconf_works = yes || AUTOCONF=no
1045 if test "x$AUTOCONF" = xno; then
1046 aux_missing="$aux_missing autoconf"
1052 # Check for python3 if available, or else python.
1053 AC_CHECK_PROG_VER(PYTHON_PROG, python3 python, --version,
1054 [Python \([0-9][0-9.]*\)],
1055 [3.[4-9]*|3.[1-9][0-9]*|[4-9].*|[1-9][0-9]*],
1056 critic_missing="$critic_missing python")
1057 PYTHON="$PYTHON_PROG -B"
1060 test -n "$critic_missing" && AC_MSG_ERROR([
1061 *** These critical programs are missing or too old:$critic_missing
1062 *** Check the INSTALL file for required versions.])
1064 test -n "$aux_missing" && AC_MSG_WARN([
1065 *** These auxiliary programs are missing or incompatible versions:$aux_missing
1066 *** some features or tests will be disabled.
1067 *** Check the INSTALL file for required versions.])
1069 # if using special system headers, find out the compiler's sekrit
1070 # header directory and add that to the list. NOTE: Only does the right
1071 # thing on a system that doesn't need fixincludes. (Not presently a problem.)
1072 if test -n "$sysheaders"; then
1073 SYSINCLUDES=-nostdinc
1074 for d in include include-fixed; do
1075 i=`$CC -print-file-name="$d"` && test "x$i" != x && test "x$i" != "x$d" &&
1076 SYSINCLUDES="$SYSINCLUDES -isystem $i"
1078 SYSINCLUDES="$SYSINCLUDES \
1079 -isystem `echo $sysheaders | sed 's/:/ -isystem /g'`"
1080 if test -n "$CXX"; then
1082 for cxxheaders in `$CXX -v -S -x c++ /dev/null -o /dev/null 2>&1 \
1083 | sed -n -e '1,/#include/d' -e 's/^ \(\/.*\/[cg]++\)/\1/p'`; do
1084 test "x$cxxheaders" != x &&
1085 CXX_SYSINCLUDES="$CXX_SYSINCLUDES -isystem $cxxheaders"
1089 AC_SUBST(SYSINCLUDES)
1090 AC_SUBST(CXX_SYSINCLUDES)
1092 # Obtain some C++ header file paths. This is used to make a local
1093 # copy of those headers in Makerules.
1094 if test -n "$CXX"; then
1095 find_cxx_header () {
1096 echo "#include <$1>" | $CXX -M -MP -x c++ - 2>/dev/null \
1097 | sed -n "\,$1:,{s/:\$//;p}"
1099 CXX_CSTDLIB_HEADER="$(find_cxx_header cstdlib)"
1100 CXX_CMATH_HEADER="$(find_cxx_header cmath)"
1101 CXX_BITS_STD_ABS_H="$(find_cxx_header bits/std_abs.h)"
1103 AC_SUBST(CXX_CSTDLIB_HEADER)
1104 AC_SUBST(CXX_CMATH_HEADER)
1105 AC_SUBST(CXX_BITS_STD_ABS_H)
1107 # Test if LD_LIBRARY_PATH contains the notation for the current directory
1108 # since this would lead to problems installing/building glibc.
1109 # LD_LIBRARY_PATH contains the current directory if one of the following
1111 # - one of the terminals (":" and ";") is the first or last sign
1112 # - two terminals occur directly after each other
1113 # - the path contains an element with a dot in it
1114 AC_MSG_CHECKING(LD_LIBRARY_PATH variable)
1116 case ${LD_LIBRARY_PATH} in
1117 [:\;]* | *[:\;] | *[:\;][:\;]* | *[:\;]. | .[:\;]*| . | *[:\;].[:\;]* )
1118 ld_library_path_setting="contains current directory"
1121 ld_library_path_setting="ok"
1125 AC_MSG_RESULT($ld_library_path_setting)
1126 if test "$ld_library_path_setting" != "ok"; then
1128 *** LD_LIBRARY_PATH shouldn't contain the current directory when
1129 *** building glibc. Please change the environment variable
1130 *** and run configure again.])
1133 AC_PATH_PROG(BASH_SHELL, bash, no)
1135 AC_PATH_PROG(PERL, perl, no)
1136 if test "$PERL" != no &&
1137 (eval `$PERL -V:apiversion`; test `expr "$apiversion" \< 5` -ne 0); then
1140 AC_PATH_PROG(INSTALL_INFO, install-info, no,
1141 $PATH:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin)
1143 AC_CACHE_CHECK(for .set assembler directive, libc_cv_asm_set_directive, [dnl
1144 cat > conftest.s <<EOF
1147 .set glibc_conftest_frobozz,foo
1148 .globl glibc_conftest_frobozz
1150 # The alpha-dec-osf1 assembler gives only a warning for `.set'
1151 # (but it doesn't work), so we must do a linking check to be sure.
1152 cat > conftest1.c <<\EOF
1153 extern int glibc_conftest_frobozz;
1154 void _start() { glibc_conftest_frobozz = 1; }
1156 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
1157 -nostartfiles -nostdlib $no_ssp \
1158 -o conftest conftest.s conftest1.c 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
1159 libc_cv_asm_set_directive=yes
1161 libc_cv_asm_set_directive=no
1164 if test $libc_cv_asm_set_directive = yes; then
1165 AC_DEFINE(HAVE_ASM_SET_DIRECTIVE)
1168 AC_CACHE_CHECK(linker support for protected data symbol,
1169 libc_cv_protected_data,
1170 [cat > conftest.c <<EOF
1171 int bar __attribute__ ((visibility ("protected"))) = 1;
1173 libc_cv_protected_data=no
1174 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -o conftest.so); then
1175 cat > conftest.c <<EOF
1177 int main (void) { return bar; }
1179 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp conftest.c -o conftest conftest.so); then
1180 libc_cv_protected_data=yes
1185 AC_SUBST(libc_cv_protected_data)
1187 AC_CACHE_CHECK(linker support for INSERT in linker script,
1189 [cat > conftest.c <<EOF
1190 const int __attribute__ ((section(".bar"))) bar = 0x12345678;
1191 int test (void) { return bar; }
1193 cat > conftest.t <<EOF
1198 INSERT AFTER .rela.dyn;
1201 if AC_TRY_COMMAND([${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -Wl,-T,conftest.t -o conftest.so]); then
1206 AC_SUBST(libc_cv_insert)
1208 AC_CACHE_CHECK(for broken __attribute__((alias())),
1209 libc_cv_broken_alias_attribute,
1210 [cat > conftest.c <<EOF
1211 extern int foo (int x) __asm ("xyzzy");
1212 int bar (int x) { return x; }
1213 extern __typeof (bar) foo __attribute ((weak, alias ("bar")));
1215 extern __typeof (dfoo) dfoo __asm ("abccb");
1218 libc_cv_broken_alias_attribute=yes
1219 if AC_TRY_COMMAND(${CC-cc} -Werror -S conftest.c -o conftest.s 1>&AS_MESSAGE_LOG_FD); then
1220 if grep 'xyzzy' conftest.s >/dev/null &&
1221 grep 'abccb' conftest.s >/dev/null; then
1222 libc_cv_broken_alias_attribute=no
1225 rm -f conftest.c conftest.s
1227 if test $libc_cv_broken_alias_attribute = yes; then
1228 AC_MSG_ERROR(working alias attribute support required)
1231 AC_CACHE_CHECK(whether to put _rtld_local into .sdata section,
1232 libc_cv_have_sdata_section,
1233 [echo "int i;" > conftest.c
1234 libc_cv_have_sdata_section=no
1235 if ${CC-cc} $LDFLAGS -fPIC -shared -Wl,--verbose conftest.c -o conftest.so 2>&1 \
1236 | grep '\.sdata' >/dev/null; then
1237 libc_cv_have_sdata_section=yes
1239 rm -f conftest.c conftest.so
1241 if test $libc_cv_have_sdata_section = yes; then
1242 AC_DEFINE(HAVE_SDATA_SECTION)
1245 AC_CACHE_CHECK(whether to use .ctors/.dtors header and trailer,
1246 libc_cv_ctors_header, [dnl
1247 libc_cv_ctors_header=yes
1248 LIBC_TRY_LINK_STATIC([
1249 __attribute__ ((constructor)) void ctor (void) { asm (""); }
1250 __attribute__ ((destructor)) void dtor (void) { asm (""); }
1253 AS_IF([$READELF -WS conftest$ac_exeext | $AWK '
1254 { gsub(/\@<:@ */, "@<:@") }
1255 $2 == ".ctors" || $2 == ".dtors" {
1256 size = strtonum("0x" $6)
1257 align = strtonum("0x" $NF)
1259 stub@<:@$2@:>@ = size == align * 2
1262 ctors_ok = !seen@<:@".ctors"@:>@ || stub@<:@".ctors"@:>@
1263 dtors_ok = !seen@<:@".dtors"@:>@ || stub@<:@".dtors"@:>@
1264 exit ((ctors_ok && dtors_ok) ? 0 : 1)
1266 '], [libc_cv_ctors_header=no])
1268 AC_MSG_ERROR([missing __attribute__ ((constructor)) support??])
1271 if test $libc_cv_ctors_header = no; then
1272 AC_DEFINE(NO_CTORS_DTORS_SECTIONS)
1275 AC_CACHE_CHECK(for libunwind-support in compiler,
1276 libc_cv_cc_with_libunwind, [
1277 cat > conftest.c <<EOF
1278 int main (void) { return 0; }
1280 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -static -o conftest \
1281 conftest.c -v 2>&1 >/dev/null | grep ' -lunwind ' >/dev/null; then
1282 libc_cv_cc_with_libunwind=yes
1284 libc_cv_cc_with_libunwind=no
1287 AC_SUBST(libc_cv_cc_with_libunwind)
1288 if test $libc_cv_cc_with_libunwind = yes; then
1289 AC_DEFINE(HAVE_CC_WITH_LIBUNWIND)
1293 AC_CACHE_CHECK(whether --noexecstack is desirable for .S files,
1294 libc_cv_as_noexecstack, [dnl
1295 cat > conftest.c <<EOF
1298 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS
1299 -S -o conftest.s conftest.c 1>&AS_MESSAGE_LOG_FD]) \
1300 && grep .note.GNU-stack conftest.s >/dev/null \
1301 && AC_TRY_COMMAND([${CC-cc} $ASFLAGS -Wa,--noexecstack
1302 -c -o conftest.o conftest.s 1>&AS_MESSAGE_LOG_FD])
1304 libc_cv_as_noexecstack=yes
1306 libc_cv_as_noexecstack=no
1309 if test $libc_cv_as_noexecstack = yes; then
1310 ASFLAGS_config="$ASFLAGS_config -Wa,--noexecstack"
1312 AC_SUBST(ASFLAGS_config)
1314 AC_CACHE_CHECK(for -z combreloc,
1315 libc_cv_z_combreloc, [dnl
1316 cat > conftest.c <<EOF
1317 extern int bar (int);
1319 int foo (void) { return bar (mumble); }
1321 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1322 -fPIC -shared $no_ssp -o conftest.so conftest.c
1323 -nostdlib -nostartfiles
1324 -Wl,-z,combreloc 1>&AS_MESSAGE_LOG_FD])
1326 dnl The following test is a bit weak. We must use a tool which can test
1327 dnl cross-platform since the gcc used can be a cross compiler. Without
1328 dnl introducing new options this is not easily doable. Instead use a tool
1329 dnl which always is cross-platform: readelf. To detect whether -z combreloc
1330 dnl look for a section named .rel.dyn or .rela.dyn.
1331 if $READELF -S conftest.so | grep -E '.rela?.dyn' > /dev/null; then
1332 libc_cv_z_combreloc=yes
1334 libc_cv_z_combreloc=no
1337 libc_cv_z_combreloc=no
1340 if test "$libc_cv_z_combreloc" = yes; then
1341 AC_DEFINE(HAVE_Z_COMBRELOC)
1343 AC_SUBST(libc_cv_z_combreloc)
1345 LIBC_LINKER_FEATURE([-z execstack], [-Wl,-z,execstack],
1346 [libc_cv_z_execstack=yes], [libc_cv_z_execstack=no])
1347 AC_SUBST(libc_cv_z_execstack)
1349 LIBC_LINKER_FEATURE([--no-dynamic-linker],
1350 [-Wl,--no-dynamic-linker],
1351 [libc_cv_no_dynamic_linker=yes],
1352 [libc_cv_no_dynamic_linker=no])
1353 LIBC_CONFIG_VAR([have-no-dynamic-linker], [$libc_cv_no_dynamic_linker])
1355 AC_CACHE_CHECK(for -static-pie, libc_cv_static_pie, [dnl
1356 LIBC_TRY_CC_OPTION([-static-pie],
1357 [libc_cv_static_pie=yes],
1358 [libc_cv_static_pie=no])
1360 LIBC_CONFIG_VAR([have-static-pie], [$libc_cv_static_pie])
1362 AC_CACHE_CHECK(for -fpie, libc_cv_fpie, [dnl
1363 LIBC_TRY_CC_OPTION([-fpie], [libc_cv_fpie=yes], [libc_cv_fpie=no])
1366 AC_SUBST(libc_cv_fpie)
1368 AC_CACHE_CHECK(for --hash-style option,
1369 libc_cv_hashstyle, [dnl
1370 cat > conftest.c <<EOF
1371 int _start (void) { return 42; }
1373 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp
1374 -fPIC -shared -o conftest.so conftest.c
1375 -Wl,--hash-style=both -nostdlib 1>&AS_MESSAGE_LOG_FD])
1377 libc_cv_hashstyle=yes
1379 libc_cv_hashstyle=no
1382 AC_SUBST(libc_cv_hashstyle)
1384 # The linker's default -shared behavior is good enough if it
1385 # does these things that our custom linker scripts ensure that
1386 # all allocated NOTE sections come first.
1387 if test "$use_default_link" = default; then
1388 AC_CACHE_CHECK([for sufficient default -shared layout],
1389 libc_cv_use_default_link, [dnl
1390 libc_cv_use_default_link=no
1391 cat > conftest.s <<\EOF
1392 .section .note.a,"a",%note
1397 .section .note.b,"a",%note
1403 if AC_TRY_COMMAND([dnl
1404 ${CC-cc} $ASFLAGS -shared -o conftest.so conftest.s 1>&AS_MESSAGE_LOG_FD]) &&
1405 ac_try=`$READELF -S conftest.so | sed -n \
1407 s/^ *\[ *[1-9][0-9]*\] *\([^ ][^ ]*\) *\([^ ][^ ]*\) .*$/\2 \1/
1413 libc_seen_a=no libc_seen_b=no
1415 while test $# -ge 2 -a "$1" = NOTE; do
1417 .note.a) libc_seen_a=yes ;;
1418 .note.b) libc_seen_b=yes ;;
1422 case "$libc_seen_a$libc_seen_b" in
1424 libc_cv_use_default_link=yes
1427 echo >&AS_MESSAGE_LOG_FD "\
1428 $libc_seen_a$libc_seen_b from:
1434 use_default_link=$libc_cv_use_default_link
1437 AC_CACHE_CHECK(for GLOB_DAT reloc,
1438 libc_cv_has_glob_dat, [dnl
1439 cat > conftest.c <<EOF
1441 int foo (void) { return mumble; }
1443 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1444 -fPIC -shared -o conftest.so conftest.c
1445 -nostdlib -nostartfiles $no_ssp
1446 1>&AS_MESSAGE_LOG_FD])
1448 dnl look for GLOB_DAT relocation.
1449 if $READELF -rW conftest.so | grep '_GLOB_DAT' > /dev/null; then
1450 libc_cv_has_glob_dat=yes
1452 libc_cv_has_glob_dat=no
1455 libc_cv_has_glob_dat=no
1458 AC_SUBST(libc_cv_has_glob_dat)
1460 AC_CACHE_CHECK(linker output format, libc_cv_output_format, [dnl
1461 if libc_cv_output_format=`
1462 ${CC-cc} -nostartfiles -nostdlib $no_ssp -Wl,--print-output-format 2>&AS_MESSAGE_LOG_FD`
1466 libc_cv_output_format=
1468 test -n "$libc_cv_output_format" || libc_cv_output_format=unknown])
1469 AC_SUBST(libc_cv_output_format)
1471 AC_CACHE_CHECK(for -fno-toplevel-reorder -fno-section-anchors, libc_cv_fno_toplevel_reorder, [dnl
1472 cat > conftest.c <<EOF
1475 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fno-toplevel-reorder -fno-section-anchors
1476 conftest.c 1>&AS_MESSAGE_LOG_FD])
1478 libc_cv_fno_toplevel_reorder=yes
1480 libc_cv_fno_toplevel_reorder=no
1483 if test $libc_cv_fno_toplevel_reorder = yes; then
1484 fno_unit_at_a_time="-fno-toplevel-reorder -fno-section-anchors"
1486 fno_unit_at_a_time=-fno-unit-at-a-time
1488 AC_SUBST(fno_unit_at_a_time)
1490 AC_CACHE_CHECK([for -mtls-dialect=gnu2], libc_cv_mtls_dialect_gnu2,
1492 cat > conftest.c <<EOF
1499 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fPIC -mtls-dialect=gnu2
1500 conftest.c 1>&AS_MESSAGE_LOG_FD])
1502 libc_cv_mtls_dialect_gnu2=yes
1504 libc_cv_mtls_dialect_gnu2=no
1507 AC_SUBST(libc_cv_mtls_dialect_gnu2)
1508 LIBC_CONFIG_VAR([have-mtls-dialect-gnu2], [$libc_cv_mtls_dialect_gnu2])
1510 AC_CACHE_CHECK(whether cc puts quotes around section names,
1511 libc_cv_have_section_quotes,
1512 [cat > conftest.c <<EOF
1513 static const int foo
1514 __attribute__ ((section ("bar"))) = 1;
1516 if ${CC-cc} -S conftest.c -o conftest.s; then
1517 if grep '\.section.*"bar"' conftest.s >/dev/null; then
1518 libc_cv_have_section_quotes=yes
1520 libc_cv_have_section_quotes=no
1523 libc_cv_have_section_quotes=unknown
1525 rm -f conftest.{c,s}
1527 if test $libc_cv_have_section_quotes = yes; then
1528 AC_DEFINE(HAVE_SECTION_QUOTES)
1531 AC_CACHE_CHECK(for __builtin_memset, libc_cv_gcc_builtin_memset, [dnl
1532 cat > conftest.c <<\EOF
1535 __builtin_memset (x, 0, 1000);
1539 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "memset" > /dev/null]);
1541 libc_cv_gcc_builtin_memset=no
1543 libc_cv_gcc_builtin_memset=yes
1546 if test "$libc_cv_gcc_builtin_memset" = yes ; then
1547 AC_DEFINE(HAVE_BUILTIN_MEMSET)
1550 AC_CACHE_CHECK(for redirection of built-in functions, libc_cv_gcc_builtin_redirection, [dnl
1551 cat > conftest.c <<\EOF
1552 extern char *strstr (const char *, const char *) __asm ("my_strstr");
1553 char *foo (const char *a, const char *b)
1555 return __builtin_strstr (a, b);
1559 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "my_strstr" > /dev/null]);
1561 libc_cv_gcc_builtin_redirection=yes
1563 libc_cv_gcc_builtin_redirection=no
1566 if test "$libc_cv_gcc_builtin_redirection" = no; then
1567 AC_MSG_ERROR([support for the symbol redirection needed])
1570 dnl Determine how to disable generation of FMA instructions.
1571 AC_CACHE_CHECK([for compiler option to disable generation of FMA instructions],
1572 libc_cv_cc_nofma, [dnl
1574 for opt in -ffp-contract=off -mno-fused-madd; do
1575 LIBC_TRY_CC_OPTION([$opt], [libc_cv_cc_nofma=$opt; break])
1577 AC_SUBST(libc_cv_cc_nofma)
1579 if test -n "$submachine"; then
1580 AC_CACHE_CHECK([for compiler option for CPU variant],
1581 libc_cv_cc_submachine, [dnl
1582 libc_cv_cc_submachine=no
1583 for opt in "-march=$submachine" "-mcpu=$submachine"; do
1584 LIBC_TRY_CC_OPTION([$opt], [
1585 libc_cv_cc_submachine="$opt"
1588 if test "x$libc_cv_cc_submachine" = xno; then
1589 AC_MSG_ERROR([${CC-cc} does not support $submachine])
1592 AC_SUBST(libc_cv_cc_submachine)
1594 AC_CACHE_CHECK(if $CC accepts -fno-tree-loop-distribute-patterns with \
1595 __attribute__ ((__optimize__)), libc_cv_cc_loop_to_function, [dnl
1596 cat > conftest.c <<EOF
1598 __attribute__ ((__optimize__ ("-fno-tree-loop-distribute-patterns")))
1601 libc_cv_cc_loop_to_function=no
1602 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -c conftest.c])
1604 libc_cv_cc_loop_to_function=yes
1607 if test $libc_cv_cc_loop_to_function = yes; then
1608 AC_DEFINE(HAVE_CC_INHIBIT_LOOP_TO_LIBCALL)
1610 AC_SUBST(libc_cv_cc_loop_to_function)
1612 dnl Check whether we have the gd library available.
1613 AC_MSG_CHECKING(for libgd)
1614 if test "$with_gd" != "no"; then
1615 old_CFLAGS="$CFLAGS"
1616 CFLAGS="$CFLAGS $libgd_include"
1617 old_LDFLAGS="$LDFLAGS"
1618 LDFLAGS="$LDFLAGS $libgd_ldflags"
1620 LIBS="$LIBS -lgd -lpng -lz -lm"
1621 AC_TRY_LINK([#include <gd.h>], [gdImagePng (0, 0)], LIBGD=yes, LIBGD=no)
1622 CFLAGS="$old_CFLAGS"
1623 LDFLAGS="$old_LDFLAGS"
1628 AC_MSG_RESULT($LIBGD)
1632 if test x$with_selinux = xno ; then
1635 # See if we have the SELinux library
1636 AC_CHECK_LIB(selinux, is_selinux_enabled,
1637 have_selinux=yes, have_selinux=no)
1638 if test x$with_selinux = xyes ; then
1639 if test x$have_selinux = xno ; then
1640 AC_MSG_ERROR([SELinux explicitly required, but SELinux library not found])
1644 # Check if we're building with SELinux support.
1645 if test "x$have_selinux" = xyes; then
1646 AC_DEFINE(HAVE_SELINUX, 1, [SELinux support])
1648 # See if we have the libaudit library
1649 AC_CHECK_LIB(audit, audit_log_user_avc_message,
1650 have_libaudit=yes, have_libaudit=no)
1651 if test "x$have_libaudit" = xyes; then
1652 AC_DEFINE(HAVE_LIBAUDIT, 1, [SELinux libaudit support])
1654 AC_SUBST(have_libaudit)
1656 # See if we have the libcap library
1657 AC_CHECK_LIB(cap, cap_init, have_libcap=yes, have_libcap=no)
1658 if test "x$have_libcap" = xyes; then
1659 AC_DEFINE(HAVE_LIBCAP, 1, [SELinux libcap support])
1661 AC_SUBST(have_libcap)
1663 AC_SUBST(have_selinux)
1666 dnl Check for silly hacked compilers predefining _FORTIFY_SOURCE.
1667 dnl Since we are building the implementations of the fortified functions here,
1668 dnl having the macro defined interacts very badly.
1669 AC_CACHE_CHECK([for _FORTIFY_SOURCE predefine], libc_cv_predef_fortify_source,
1670 [AC_TRY_COMPILE([], [
1671 #ifdef _FORTIFY_SOURCE
1674 [libc_cv_predef_fortify_source=no],
1675 [libc_cv_predef_fortify_source=yes])])
1676 if test $libc_cv_predef_fortify_source = yes; then
1677 CPPUNDEFS="${CPPUNDEFS:+$CPPUNDEFS }-U_FORTIFY_SOURCE"
1681 # Some linkers on some architectures support __ehdr_start but with
1682 # bugs. Make sure usage of it does not create relocations in the
1683 # output (as the linker should resolve them all for us).
1684 AC_CACHE_CHECK([whether the linker provides working __ehdr_start],
1685 libc_cv_ehdr_start, [
1686 old_CFLAGS="$CFLAGS"
1687 old_LDFLAGS="$LDFLAGS"
1689 CFLAGS="$CFLAGS -fPIC"
1690 LDFLAGS="$LDFLAGS -nostdlib -nostartfiles -shared $no_ssp"
1692 AC_LINK_IFELSE([AC_LANG_SOURCE([
1697 extern const Ehdr __ehdr_start __attribute__ ((visibility ("hidden")));
1698 long ehdr (void) { return __ehdr_start.val; }
1700 [if $READELF -r conftest | grep -F __ehdr_start >/dev/null; then
1701 libc_cv_ehdr_start=broken
1703 libc_cv_ehdr_start=yes
1704 fi], [libc_cv_ehdr_start=no])
1705 CFLAGS="$old_CFLAGS"
1706 LDFLAGS="$old_LDFLAGS"
1709 if test "$libc_cv_ehdr_start" = yes; then
1710 AC_DEFINE([HAVE_EHDR_START])
1711 elif test "$libc_cv_ehdr_start" = broken; then
1712 AC_MSG_WARN([linker is broken -- you should upgrade])
1715 AC_CACHE_CHECK(for __builtin_trap with no external dependencies,
1716 libc_cv_builtin_trap, [dnl
1717 libc_cv_builtin_trap=no
1718 AC_TRY_COMPILE([], [__builtin_trap ()], [
1719 libc_undefs=`$NM -u conftest.o |
1720 LC_ALL=C $AWK '$1 == "U" { print $2 | "sort -u"; next } { exit(1) }' \
1721 2>&AS_MESSAGE_LOG_FD` || {
1722 AC_MSG_ERROR([confusing output from $NM -u])
1724 echo >&AS_MESSAGE_LOG_FD "libc_undefs='$libc_undefs'"
1725 if test -z "$libc_undefs"; then
1726 libc_cv_builtin_trap=yes
1728 if test $libc_cv_builtin_trap = yes; then
1729 AC_DEFINE([HAVE_BUILTIN_TRAP])
1732 dnl C++ feature tests.
1735 AC_CACHE_CHECK([whether the C++ compiler supports thread_local],
1736 libc_cv_cxx_thread_local, [
1737 old_CXXFLAGS="$CXXFLAGS"
1738 CXXFLAGS="$CXXFLAGS -std=gnu++11"
1739 AC_COMPILE_IFELSE([AC_LANG_SOURCE([
1742 // Compiler support.
1749 S * get () { return &s; }
1751 // libstdc++ support.
1752 #ifndef _GLIBCXX_HAVE___CXA_THREAD_ATEXIT_IMPL
1753 #error __cxa_thread_atexit_impl not supported
1756 [libc_cv_cxx_thread_local=yes],
1757 [libc_cv_cxx_thread_local=no])
1758 CXXFLAGS="$old_CXXFLAGS"
1760 AC_SUBST(libc_cv_cxx_thread_local)
1763 dnl End of C++ feature tests.
1765 ### End of automated tests.
1766 ### Now run sysdeps configure fragments.
1768 # They also can set these variables.
1770 ldd_rewrite_script=no
1771 libc_cv_sysconfdir=$sysconfdir
1772 libc_cv_localstatedir=$localstatedir
1773 libc_cv_gcc_unwind_find_fde=no
1776 # Iterate over all the sysdep directories we will use, running their
1777 # configure fragments.
1778 for dir in $sysnames; do
1781 *) dest=$srcdir/$dir ;;
1783 if test -r $dest/configure; then
1784 AC_MSG_RESULT(running configure fragment for $dir)
1789 if test x"$build_mathvec" = xnotset; then
1792 LIBC_CONFIG_VAR([build-mathvec], [$build_mathvec])
1794 AC_SUBST(libc_extra_cflags)
1795 AC_SUBST(libc_extra_cppflags)
1797 if test x$libc_cv_gcc_unwind_find_fde = xyes; then
1798 AC_DEFINE(EXPORT_UNWIND_FIND_FDE)
1800 AC_SUBST(libc_cv_gcc_unwind_find_fde)
1802 # A sysdeps configure fragment can reset this if IFUNC is not actually
1803 # usable even though the assembler knows how to generate the symbol type.
1804 if test x"$libc_cv_ld_gnu_indirect_function" = xyes; then
1805 AC_DEFINE(HAVE_IFUNC)
1807 LIBC_CONFIG_VAR([have-ifunc], [$libc_cv_ld_gnu_indirect_function])
1809 if test x"$libc_cv_gcc_indirect_function" = xyes; then
1810 AC_DEFINE(HAVE_GCC_IFUNC)
1813 # This is far from the AC_ARG_ENABLE that sets it so that a sysdeps
1814 # configure fragment can override the value to prevent this AC_DEFINE.
1816 if test "x$use_nscd" != xno; then
1817 AC_DEFINE([USE_NSCD])
1819 if test "x$build_nscd" = xdefault; then
1820 build_nscd=$use_nscd
1823 AC_SUBST(libc_cv_slibdir)
1824 AC_SUBST(libc_cv_rtlddir)
1825 AC_SUBST(libc_cv_complocaledir)
1826 AC_SUBST(libc_cv_sysconfdir)
1827 AC_SUBST(libc_cv_localstatedir)
1828 AC_SUBST(libc_cv_rootsbindir)
1830 if test x$use_ldconfig = xyes; then
1831 AC_DEFINE(USE_LDCONFIG)
1833 AC_SUBST(use_ldconfig)
1834 AC_SUBST(ldd_rewrite_script)
1839 AC_CACHE_CHECK([whether -fPIC is default], libc_cv_pic_default,
1840 [libc_cv_pic_default=yes
1841 cat > conftest.c <<EOF
1842 #if defined __PIC__ || defined __pic__ || defined PIC || defined pic
1843 # error PIC is default.
1846 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1847 libc_cv_pic_default=no
1850 AC_SUBST(libc_cv_pic_default)
1852 AC_CACHE_CHECK([whether -fPIE is default], libc_cv_cc_pie_default,
1853 [libc_cv_cc_pie_default=yes
1854 cat > conftest.c <<EOF
1855 #if defined __PIE__ || defined __pie__ || defined PIE || defined pie
1856 # error PIE is default.
1859 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1860 libc_cv_cc_pie_default=no
1863 libc_cv_pie_default=$libc_cv_cc_pie_default
1864 AC_SUBST(libc_cv_cc_pie_default)
1865 AC_SUBST(libc_cv_pie_default)
1867 # Set the `multidir' variable by grabbing the variable from the compiler.
1868 # We do it once and save the result in a generated makefile.
1869 libc_cv_multidir=`${CC-cc} $CFLAGS $CPPFLAGS -print-multi-directory`
1870 AC_SUBST(libc_cv_multidir)
1872 if test "$static_pie" = yes; then
1873 # The linker must support --no-dynamic-linker.
1874 if test "$libc_cv_no_dynamic_linker" != yes; then
1875 AC_MSG_ERROR([linker support for --no-dynamic-linker needed])
1878 libc_cv_pie_default=yes
1879 AC_DEFINE(ENABLE_STATIC_PIE)
1881 LIBC_CONFIG_VAR([enable-static-pie], [$static_pie])
1884 AC_SUBST(static_nss)
1888 dnl See sysdeps/mach/configure.ac for this variable.
1889 AC_SUBST(mach_interface_list)
1891 VERSION=`sed -n -e 's/^#define VERSION "\([^"]*\)"/\1/p' < $srcdir/version.h`
1892 RELEASE=`sed -n -e 's/^#define RELEASE "\([^"]*\)"/\1/p' < $srcdir/version.h`
1896 AC_CONFIG_FILES([config.make Makefile])
1897 AC_CONFIG_COMMANDS([default],[[
1898 case $CONFIG_FILES in *config.make*)
1899 echo "$config_vars" >> config.make;;
1901 test -d bits || mkdir bits]],[[config_vars='$config_vars']])