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)
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 $srcdir; pwd -P`" = "`pwd -P`"; then
84 AC_MSG_ERROR([you must configure in a separate build directory])
87 # This will get text that should go into config.make.
90 # Check for a --with-gd argument and set libgd-LDFLAGS in config.make.
92 AS_HELP_STRING([--with-gd=DIR],
93 [find libgd include dir and library with prefix DIR]),
97 *) libgd_include="-I$withval/include"
98 libgd_ldflags="-L$withval/lib" ;;
101 AC_ARG_WITH([gd-include],
102 AS_HELP_STRING([--with-gd-include=DIR],
103 [find libgd include files in DIR]),
105 case "$with_gd_include" in
107 *) libgd_include="-I$withval" ;;
110 AC_ARG_WITH([gd-lib],
111 AS_HELP_STRING([--with-gd-lib=DIR],
112 [find libgd library files in DIR]),
114 case "$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 = $libgd_ldflags"
129 dnl Arguments to specify presence of other packages/features.
130 AC_ARG_WITH([binutils],
131 AS_HELP_STRING([--with-binutils=PATH],
132 [specify location of binutils (as and ld)]),
133 [path_binutils=$withval],
135 AC_ARG_WITH([selinux],
136 AS_HELP_STRING([--with-selinux],
137 [if building with SELinux support]),
138 [with_selinux=$withval],
141 AC_ARG_WITH([headers],
142 AS_HELP_STRING([--with-headers=PATH],
143 [location of system headers to use
144 (for example /usr/src/linux/include)
145 @<:@default=compiler default@:>@]),
146 [sysheaders=$withval],
150 dnl Additional build flags injection.
151 AC_ARG_WITH([nonshared-cflags],
152 AS_HELP_STRING([--with-nonshared-cflags=CFLAGS],
153 [build nonshared libraries with additional CFLAGS]),
154 [extra_nonshared_cflags=$withval],
155 [extra_nonshared_cflags=])
156 AC_SUBST(extra_nonshared_cflags)
157 AC_ARG_WITH([rtld-early-cflags],
158 AS_HELP_STRING([--with-rtld-early-cflags=CFLAGS],
159 [build early initialization with additional CFLAGS]),
160 [rtld_early_cflags=$withval],
161 [rtld_early_cflags=])
162 AC_SUBST(rtld_early_cflags)
164 AC_ARG_WITH([timeoutfactor],
165 AS_HELP_STRING([--with-timeoutfactor=NUM],
166 [specify an integer to scale the timeout]),
167 [timeoutfactor=$withval],
169 AC_DEFINE_UNQUOTED(TIMEOUTFACTOR, $timeoutfactor)
171 AC_ARG_ENABLE([sanity-checks],
172 AS_HELP_STRING([--disable-sanity-checks],
173 [really do not use threads (should not be used except in special situations) @<:@default=yes@:>@]),
174 [enable_sanity=$enableval],
177 AC_ARG_ENABLE([shared],
178 AS_HELP_STRING([--enable-shared],
179 [build shared library @<:@default=yes if GNU ld@:>@]),
182 AC_ARG_ENABLE([profile],
183 AS_HELP_STRING([--enable-profile],
184 [build profiled library @<:@default=no@:>@]),
185 [profile=$enableval],
187 AC_ARG_ENABLE([default-pie],
188 AS_HELP_STRING([--disable-default-pie],
189 [Do not build glibc programs and the testsuite as PIE @<:@default=no@:>@]),
190 [default_pie=$enableval],
192 AC_ARG_ENABLE([timezone-tools],
193 AS_HELP_STRING([--disable-timezone-tools],
194 [do not install timezone tools @<:@default=install@:>@]),
195 [enable_timezone_tools=$enableval],
196 [enable_timezone_tools=yes])
197 AC_SUBST(enable_timezone_tools)
199 AC_ARG_ENABLE([hardcoded-path-in-tests],
200 AS_HELP_STRING([--enable-hardcoded-path-in-tests],
201 [hardcode newly built glibc path in tests @<:@default=no@:>@]),
202 [hardcoded_path_in_tests=$enableval],
203 [hardcoded_path_in_tests=no])
204 AC_SUBST(hardcoded_path_in_tests)
206 AC_ARG_ENABLE([hidden-plt],
207 AS_HELP_STRING([--disable-hidden-plt],
208 [do not hide internal function calls to avoid PLT]),
211 if test "x$hidden" = xno; then
215 AC_ARG_ENABLE([bind-now],
216 AS_HELP_STRING([--enable-bind-now],
217 [disable lazy relocations in DSOs]),
218 [bindnow=$enableval],
221 if test "x$bindnow" = xyes; then
225 dnl Build glibc with -fstack-protector, -fstack-protector-all, or
226 dnl -fstack-protector-strong.
227 AC_ARG_ENABLE([stack-protector],
228 AS_HELP_STRING([--enable-stack-protector=@<:@yes|no|all|strong@:>@],
229 [Use -fstack-protector[-all|-strong] to detect glibc buffer overflows]),
230 [enable_stack_protector=$enableval],
231 [enable_stack_protector=no])
232 case "$enable_stack_protector" in
233 all|yes|no|strong) ;;
234 *) AC_MSG_ERROR([Not a valid argument for --enable-stack-protector: "$enable_stack_protector"]);;
237 dnl On some platforms we cannot use dynamic loading. We must provide
238 dnl static NSS modules.
239 AC_ARG_ENABLE([static-nss],
240 AS_HELP_STRING([--enable-static-nss],
241 [build static NSS modules @<:@default=no@:>@]),
242 [static_nss=$enableval],
244 dnl Enable static NSS also if we build no shared objects.
245 if test x"$static_nss" = xyes || test x"$shared" = xno; then
247 AC_DEFINE(DO_STATIC_NSS)
250 AC_ARG_ENABLE([force-install],
251 AS_HELP_STRING([--disable-force-install],
252 [don't force installation of files from this package, even if they are older than the installed files]),
253 [force_install=$enableval],
255 AC_SUBST(force_install)
257 AC_ARG_ENABLE([maintainer-mode],
258 AS_HELP_STRING([--enable-maintainer-mode],
259 [enable make rules and dependencies not useful (and sometimes confusing) to the casual installer]),
260 [maintainer=$enableval],
263 dnl On some platforms we allow dropping compatibility with all kernel
265 AC_ARG_ENABLE([kernel],
266 AS_HELP_STRING([--enable-kernel=VERSION],
267 [compile for compatibility with kernel not older than VERSION]),
268 [minimum_kernel=$enableval],
270 dnl Prevent unreasonable values.
271 if test "$minimum_kernel" = yes || test "$minimum_kernel" = no; then
272 # Better nothing than this.
275 if test "$minimum_kernel" = current; then
276 minimum_kernel=`uname -r 2>/dev/null` || minimum_kernel=
280 AC_ARG_ENABLE([werror],
281 AS_HELP_STRING([--disable-werror],
282 [do not build with -Werror]),
283 [enable_werror=$enableval],
285 AC_SUBST(enable_werror)
287 AC_ARG_ENABLE([multi-arch],
288 AS_HELP_STRING([--enable-multi-arch],
289 [enable single DSO with optimizations for multiple architectures]),
290 [multi_arch=$enableval],
291 [multi_arch=default])
293 AC_ARG_ENABLE([memory-tagging],
294 AS_HELP_STRING([--enable-memory-tagging],
295 [enable memory tagging if supported by the architecture @<:@default=no@:>@]),
296 [memory_tagging=$enableval],
298 if test "$memory_tagging" = yes; then
299 # Only enable this on architectures that support it.
306 AC_SUBST(memory_tagging)
308 AC_ARG_ENABLE([systemtap],
309 [AS_HELP_STRING([--enable-systemtap],
310 [enable systemtap static probe points @<:@default=no@:>@])],
311 [systemtap=$enableval],
313 if test "x$systemtap" != xno; then
314 AC_CACHE_CHECK([for systemtap static probe support], libc_cv_sdt, [dnl
316 CFLAGS="-std=gnu11 $CFLAGS"
317 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <sys/sdt.h>
318 void foo (int i, void *p)
320 asm ("" STAP_PROBE_ASM (foo, bar, STAP_PROBE_ASM_TEMPLATE (2)) ""
321 :: STAP_PROBE_ASM_OPERANDS (2, i, p));
322 }]])], [libc_cv_sdt=yes], [libc_cv_sdt=no])
323 CFLAGS="$old_CFLAGS"])
324 if test $libc_cv_sdt = yes; then
325 AC_DEFINE([USE_STAP_PROBE])
326 elif test "x$systemtap" != xauto; then
327 AC_MSG_FAILURE([systemtap support needs sys/sdt.h with asm support])
331 AC_ARG_ENABLE([build-nscd],
332 [AS_HELP_STRING([--disable-build-nscd],
333 [disable building and installing the nscd daemon])],
334 [build_nscd=$enableval],
335 [build_nscd=default])
338 # Note the use of $use_nscd is near the bottom of the file.
339 AC_ARG_ENABLE([nscd],
340 [AS_HELP_STRING([--disable-nscd],
341 [library functions will not contact the nscd daemon])],
342 [use_nscd=$enableval],
345 AC_ARG_ENABLE([pt_chown],
346 [AS_HELP_STRING([--enable-pt_chown],
347 [Enable building and installing pt_chown])],
348 [build_pt_chown=$enableval],
350 AC_SUBST(build_pt_chown)
351 if test "$build_pt_chown" = yes; then
352 AC_DEFINE(HAVE_PT_CHOWN)
355 # The abi-tags file uses a fairly simplistic model for name recognition that
356 # can't distinguish i486-pc-linux-gnu fully from i486-pc-gnu. So we mutate a
357 # $host_os of `gnu*' here to be `gnu-gnu*' just so that it can tell.
358 # This doesn't get used much beyond that, so it's fairly safe.
363 host_os=`echo $host_os | sed -e 's/gnu/gnu-gnu/'`
367 AC_ARG_ENABLE([mathvec],
368 [AS_HELP_STRING([--enable-mathvec],
369 [Enable building and installing mathvec @<:@default depends on architecture@:>@])],
370 [build_mathvec=$enableval],
371 [build_mathvec=notset])
373 AC_PREPROC_IFELSE([AC_LANG_PROGRAM([[]], [[
375 # error no CET compiler support
377 [libc_cv_compiler_default_cet=yes],
378 [libc_cv_compiler_default_cet=no])
381 AS_HELP_STRING([--enable-cet],
382 [enable Intel Control-flow Enforcement Technology (CET), x86 only]),
383 [enable_cet=$enableval],
384 [enable_cet=$libc_cv_compiler_default_cet])
387 AS_HELP_STRING([--disable-scv],
388 [syscalls will not use scv instruction, even if the kernel supports it, powerpc only]),
389 [use_scv=$enableval],
392 AS_IF([[test "$use_scv" != "no"]],[AC_DEFINE(USE_PPC_SCV)])
394 dnl Build glibc with _FORTIFY_SOURCE
395 AC_ARG_ENABLE(fortify-source,
396 AS_HELP_STRING([--enable-fortify-source@<:@=1|2|3@:>@],
397 [Use -D_FORTIFY_SOURCE=[1|2|3] to control code hardening, defaults to highest possible value supported by the build compiler.]),
398 [enable_fortify_source=$enableval],
399 [enable_fortify_source=no])
400 case "$enable_fortify_source" in
402 *) AC_MSG_ERROR([Not a valid argument for --enable-fortify-source: "$enable_fortify_source"]);;
405 # We keep the original values in `$config_*' and never modify them, so we
406 # can write them unchanged into config.make. Everything else uses
407 # $machine, $vendor, and $os, and changes them whenever convenient.
408 config_machine=$host_cpu config_vendor=$host_vendor config_os=$host_os
410 # Don't allow vendor == "unknown"
411 test "$config_vendor" = unknown && config_vendor=
412 config_os="`echo $config_os | sed 's/^unknown-//'`"
414 # Some configurations imply other options.
417 # The configure fragment of a port can modify these to supplement
418 # or override the table in the case statement below. No fragment should
419 # ever change the config_* variables, however.
420 machine=$config_machine
421 vendor=$config_vendor
427 AS_HELP_STRING([--with-cpu=CPU], [select code for CPU variant]),
430 yes|'') AC_MSG_ERROR([--with-cpu requires an argument]) ;;
432 *) submachine="$withval" ;;
436 # An preconfigure script can set this when it wants to disable the sanity
440 # A preconfigure script for a system that may or may not use fpu
441 # sysdeps directories sets this to a preprocessor conditional for
442 # whether to use such directories.
445 dnl Let sysdeps/*/preconfigure act here.
446 LIBC_PRECONFIGURE([$srcdir], [for sysdeps])
450 ### By using the undocumented --enable-hacker-mode option for configure
451 ### one can skip this test to make the configuration not fail for unsupported
454 if test -z "$enable_hacker_mode" && test x"$libc_config_ok" != xyes; then
455 case "$machine-$host_os" in
460 *** The GNU C library is currently unavailable for this platform.
461 *** If you are interested in seeing glibc on this platform visit
462 *** the "How to submit a new port" in the wiki:
463 *** https://sourceware.org/glibc/wiki/#Development
464 *** and join the community!])
469 # Set base_machine if not set by a preconfigure fragment.
470 test -n "$base_machine" || base_machine=$machine
471 AC_SUBST(base_machine)
476 if test "$INSTALL" = "${srcdir}/scripts/install-sh -c"; then
477 # The makefiles need to use a different form to find it in $srcdir.
478 INSTALL='\$(..)./scripts/install-sh -c'
484 # Accept binutils 2.25 or newer.
486 case $($LD --version) in
488 # Accept gold 1.14 or higher
489 AC_CHECK_PROG_VER(LD, $LD, --version,
490 [GNU gold.* \([0-9][0-9]*\.[0-9.]*\)],
491 [1.1[4-9]*|1.[2-9][0-9]*|1.1[0-9][0-9]*|[2-9].*|[1-9][0-9]*],
492 LD=: critic_missing="$critic_missing GNU gold")
495 # Accept LLD 13.0.0 or higher
496 AC_CHECK_PROG_VER(LD, $LD, --version,
497 [LLD.* \([0-9][0-9]*\.[0-9.]*\)],
498 [1[3-9].*|[2-9][0-9].*],
499 LD=: critic_missing="$critic_missing LLD")
503 AC_CHECK_PROG_VER(LD, $LD, --version,
504 [GNU ld.* \([0-9][0-9]*\.[0-9.]*\)],
505 [2.1[0-9][0-9]*|2.2[5-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*],
506 LD=: critic_missing="$critic_missing GNU ld")
509 LIBC_CONFIG_VAR([with-lld], [$libc_cv_with_lld])
511 # These programs are version sensitive.
512 AC_CHECK_PROG_VER(MAKE, gnumake gmake make, --version,
513 [GNU Make[^0-9]*\([0-9][0-9.]*\)],
514 [[4-9].* | [1-9][0-9]*], critic_missing="$critic_missing make")
516 AC_CHECK_PROG_VER(MSGFMT, gnumsgfmt gmsgfmt msgfmt, --version,
517 [GNU gettext.* \([0-9]*\.[0-9.]*\)],
518 [0.10.3[6-9]* | 0.10.[4-9][0-9]* | 0.1[1-9]* | 0.[2-9][0-9]* | [1-9].*],
519 MSGFMT=: aux_missing="$aux_missing msgfmt")
520 AC_CHECK_PROG_VER(MAKEINFO, makeinfo, --version,
521 [GNU texinfo.* \([0-9][0-9.]*\)],
522 [4.[7-9]*|4.[1-9][0-9]*|[5-9].*],
523 MAKEINFO=: aux_missing="$aux_missing makeinfo")
524 AC_CHECK_PROG_VER(SED, sed, --version,
525 [GNU sed[^0-9]* \([0-9]*\.[0-9.]*\)],
526 [3.0[2-9]*|3.[1-9]*|[4-9]*],
527 SED=: aux_missing="$aux_missing sed")
528 AC_CHECK_PROG_VER(AWK, gawk, --version,
529 [GNU Awk[^0-9]*\([0-9][0-9.]*\)],
530 [3.1.[2-9]*|3.[2-9]*|[4-9]*], critic_missing="$critic_missing gawk")
531 AC_CHECK_PROG_VER(BISON, bison, --version,
532 [bison (GNU Bison) \([0-9]*\.[0-9.]*\)],
533 [2.7*|[3-9].*|[1-9][0-9]*], critic_missing="$critic_missing bison")
535 AC_CACHE_CHECK([if $CC is sufficient to build libc], libc_cv_compiler_ok, [
536 AC_PREPROC_IFELSE([AC_LANG_PROGRAM([[]], [[
537 #if !defined __GNUC__ || __GNUC__ < 6 || (__GNUC__ == 6 && __GNUC_MINOR__ < 2)
538 #error insufficient compiler
540 [libc_cv_compiler_ok=yes],
541 [libc_cv_compiler_ok=no])])
542 AS_IF([test $libc_cv_compiler_ok != yes],
543 [critic_missing="$critic_missing compiler"])
545 if test "x$maintainer" = "xyes"; then
546 AC_CHECK_PROGS(AUTOCONF, autoconf, no)
548 xno|x|x:) AUTOCONF=no ;;
551 whether $AUTOCONF${ACFLAGS:+ }$ACFLAGS works, libc_cv_autoconf_works, [dnl
552 if (cd $srcdir; $AUTOCONF $ACFLAGS configure.ac > /dev/null 2>&1); then
553 libc_cv_autoconf_works=yes
555 libc_cv_autoconf_works=no
557 test $libc_cv_autoconf_works = yes || AUTOCONF=no
560 if test "x$AUTOCONF" = xno; then
561 aux_missing="$aux_missing autoconf"
567 # Check for python3 if available, or else python.
568 AC_CHECK_PROG_VER(PYTHON_PROG, python3 python, --version,
569 [Python \([0-9][0-9.]*\)],
570 [3.[4-9]*|3.[1-9][0-9]*|[4-9].*|[1-9][0-9]*],
571 critic_missing="$critic_missing python")
572 PYTHON="$PYTHON_PROG -B"
575 test -n "$critic_missing" && AC_MSG_ERROR([
576 *** These critical programs are missing or too old:$critic_missing
577 *** Check the INSTALL file for required versions.])
579 test -n "$aux_missing" && AC_MSG_WARN([
580 *** These auxiliary programs are missing or incompatible versions:$aux_missing
581 *** some features or tests will be disabled.
582 *** Check the INSTALL file for required versions.])
585 # Determine whether to use fpu or nofpu sysdeps directories.
586 AC_CACHE_CHECK([for use of fpu sysdeps directories],
587 libc_cv_with_fp, [dnl
588 cat > conftest.c <<EOF
592 # error "no hardware floating point"
596 if ${CC-cc} $CFLAGS $CPPFLAGS -S conftest.c -o conftest.s \
597 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
601 AC_SUBST(libc_cv_with_fp)
603 AC_CACHE_CHECK(for -fstack-protector, libc_cv_ssp, [dnl
604 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector],
609 AC_CACHE_CHECK(for -fstack-protector-strong, libc_cv_ssp_strong, [dnl
610 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-strong],
611 [libc_cv_ssp_strong=yes],
612 [libc_cv_ssp_strong=no])
615 AC_CACHE_CHECK(for -fstack-protector-all, libc_cv_ssp_all, [dnl
616 LIBC_TRY_CC_OPTION([$CFLAGS $CPPFLAGS -Werror -fstack-protector-all],
617 [libc_cv_ssp_all=yes],
618 [libc_cv_ssp_all=no])
623 if test "$libc_cv_ssp" = yes; then
624 no_stack_protector="-fno-stack-protector -DSTACK_PROTECTOR_LEVEL=0"
625 AC_DEFINE(HAVE_CC_NO_STACK_PROTECTOR)
628 if test "$enable_stack_protector" = yes && test "$libc_cv_ssp" = yes; then
629 stack_protector="-fstack-protector"
630 AC_DEFINE(STACK_PROTECTOR_LEVEL, 1)
631 elif test "$enable_stack_protector" = all && test "$libc_cv_ssp_all" = yes; then
632 stack_protector="-fstack-protector-all"
633 AC_DEFINE(STACK_PROTECTOR_LEVEL, 2)
634 elif test "$enable_stack_protector" = strong && test "$libc_cv_ssp_strong" = yes; then
635 stack_protector="-fstack-protector-strong"
636 AC_DEFINE(STACK_PROTECTOR_LEVEL, 3)
638 stack_protector="-fno-stack-protector"
639 AC_DEFINE(STACK_PROTECTOR_LEVEL, 0)
641 AC_SUBST(libc_cv_ssp)
642 AC_SUBST(stack_protector)
643 AC_SUBST(no_stack_protector)
645 if test -n "$stack_protector"; then
646 dnl Don't run configure tests with stack-protection on, to avoid problems with
648 no_ssp=-fno-stack-protector
652 if test "$enable_stack_protector" != no; then
653 AC_MSG_ERROR([--enable-stack-protector=$enable_stack_protector specified, but specified level of stack protection is not supported by the compiler.])
657 # For the multi-arch option we need support in the assembler & linker.
658 AC_CACHE_CHECK([for assembler and linker STT_GNU_IFUNC support],
659 libc_cv_ld_gnu_indirect_function, [dnl
660 cat > conftest.S <<EOF
661 .type foo,%gnu_indirect_function
674 libc_cv_ld_gnu_indirect_function=no
675 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
676 -nostartfiles -nostdlib $no_ssp \
677 -o conftest conftest.S 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
678 # Do a link to see if the backend supports IFUNC relocs.
679 $READELF -r conftest 1>&AS_MESSAGE_LOG_FD
680 LC_ALL=C $READELF -Wr conftest | grep -q 'IRELATIVE\|R_SPARC_JMP_IREL' && {
681 libc_cv_ld_gnu_indirect_function=yes
686 # Check if gcc supports attribute ifunc as it is used in libc_ifunc macro.
687 AC_CACHE_CHECK([for gcc attribute ifunc support],
688 libc_cv_gcc_indirect_function, [dnl
689 cat > conftest.c <<EOF
690 extern int func (int);
691 int used_func (int a)
695 static void *resolver ()
699 extern __typeof (func) func __attribute__ ((ifunc ("resolver")));
701 libc_cv_gcc_indirect_function=no
702 if ${CC-cc} -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD \
703 2>&AS_MESSAGE_LOG_FD ; then
704 if $READELF -s conftest.o | grep IFUNC >/dev/null 2>&AS_MESSAGE_LOG_FD; then
705 libc_cv_gcc_indirect_function=yes
710 # Check if linker supports textrel relocation with ifunc (used on elf/tests).
711 # Note that it relies on libc_cv_ld_gnu_indirect_function test above.
712 AC_CACHE_CHECK([whether the linker supports textrels along with ifunc],
713 libc_cv_textrel_ifunc, [dnl
714 cat > conftest.S <<EOF
715 .type foo,%gnu_indirect_function
736 libc_cv_textrel_ifunc=no
737 if test $libc_cv_ld_gnu_indirect_function = yes; then
738 if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp -pie -o conftest conftest.S); then
739 libc_cv_textrel_ifunc=yes
743 AC_SUBST(libc_cv_textrel_ifunc)
745 # Check if CC supports attribute retain as it is used in attribute_used_retain macro.
746 AC_CACHE_CHECK([for GNU attribute retain support],
747 libc_cv_gnu_retain, [dnl
748 cat > conftest.c <<EOF
749 static int var __attribute__ ((used, retain, section ("__libc_atexit")));
751 libc_cv_gnu_retain=no
752 if ${CC-cc} -Werror -c conftest.c -o /dev/null 1>&AS_MESSAGE_LOG_FD \
753 2>&AS_MESSAGE_LOG_FD ; then
754 libc_cv_gnu_retain=yes
757 if test $libc_cv_gnu_retain = yes; then
758 AC_DEFINE(HAVE_GNU_RETAIN)
760 LIBC_CONFIG_VAR([have-gnu-retain], [$libc_cv_gnu_retain])
762 # Check if gcc warns about alias for function with incompatible types.
763 AC_CACHE_CHECK([if compiler warns about alias for function with incompatible types],
764 libc_cv_gcc_incompatible_alias, [dnl
765 cat > conftest.c <<EOF
766 int __redirect_foo (const void *s, int c);
768 __typeof (__redirect_foo) *foo_impl (void) __asm__ ("foo");
769 __typeof (__redirect_foo) *foo_impl (void)
774 extern __typeof (__redirect_foo) foo_alias __attribute__ ((alias ("foo")));
776 libc_cv_gcc_incompatible_alias=yes
777 if ${CC-cc} -Werror -c conftest.c -o conftest.o 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD ; then
778 libc_cv_gcc_incompatible_alias=no
782 if test x"$libc_cv_ld_gnu_indirect_function" != xyes; then
783 if test x"$multi_arch" = xyes; then
784 AC_MSG_ERROR([--enable-multi-arch support requires assembler and linker support])
789 if test x"$libc_cv_gcc_indirect_function" != xyes; then
790 # GCC 8+ emits a warning for alias with incompatible types and it might
791 # fail to build ifunc resolvers aliases to either weak or internal
792 # symbols. Disables multiarch build in this case.
793 if test x"$libc_cv_gcc_incompatible_alias" = xyes; then
794 AC_MSG_WARN([gcc emits a warning for alias between functions of incompatible types])
795 if test x"$multi_arch" = xyes; then
796 AC_MSG_ERROR([--enable-multi-arch support requires a gcc with gnu-indirect-function support])
798 AC_MSG_WARN([Multi-arch is disabled.])
800 elif test x"$multi_arch" = xyes; then
801 AC_MSG_WARN([--enable-multi-arch support recommends a gcc with gnu-indirect-function support.
802 Please use a gcc which supports it by default or configure gcc with --enable-gnu-indirect-function])
806 if test x"$multi_arch" != xno; then
807 multi_arch_d=/multiarch
810 # Compute the list of sysdep directories for this configuration.
811 # This can take a while to compute.
812 sysdep_dir=$srcdir/sysdeps
813 AC_MSG_CHECKING(sysdep dirs)
814 dnl We need to use [ and ] for other purposes for a while now.
816 # Make sco3.2v4 become sco3.2.4 and sunos4.1.1_U1 become sunos4.1.1.U1.
817 os="`echo $os | sed 's/\([0-9A-Z]\)[v_]\([0-9A-Z]\)/\1.\2/g'`"
819 test "x$base_os" != x || case "$os" in
826 # For sunos4.1.1, try sunos4.1.1, then sunos4.1, then sunos4, then sunos.
829 while o=`echo $tail | sed 's/\.[^.]*$//'`; test $o != $tail; do
833 o=`echo $tail | sed 's/[0-9]*$//'`
834 if test $o != $tail; then
837 # For linux-gnu, try linux-gnu, then linux.
838 o=`echo $tail | sed 's/-.*$//'`
839 if test $o != $tail; then
843 # For unix/sysv/sysv4, try unix/sysv/sysv4, then unix/sysv, then unix.
846 while b=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$b"; do
852 # For sparc/sparc32, try sparc/sparc32 and then sparc.
854 tail=$machine${submachine:+/$submachine}
855 while m=`echo $tail | sed 's@^\(.*\)/\([^/]*\)$@& \1@'`; test -n "$m"; do
857 # Prepend the machine's FPU directory unless the architecture specific
858 # preconfigure disables it.
859 if test "$libc_cv_with_fp" = yes; then
864 # For each machine term, try it with and then without /multiarch.
865 for try_fpu in $maybe_fpu ''; do
866 for try_multi in $multi_arch_d ''; do
867 mach="$mach /$1$try_fpu$try_multi"
873 dnl We are done with glob and regexp uses of [ and ]; return to autoconf.
876 # Find what sysdep directories exist.
878 for b in $base ''; do
879 for m0 in $mach ''; do
880 for v in /$vendor ''; do
881 test "$v" = / && continue
882 for o in /$ostry ''; do
883 test "$o" = / && continue
884 for m in $mach ''; do
885 try_suffix="$m0$b$v$o$m"
886 if test -n "$try_suffix"; then
887 try_srcdir="${srcdir}/"
888 try="sysdeps$try_suffix"
889 test -n "$enable_debug_configure" &&
890 echo "$0 [DEBUG]: try $try" >&2
891 if test -d "$try_srcdir$try"; then
892 sysnames="$sysnames $try"
893 { test -n "$o" || test -n "$b"; } && os_used=t
894 { test -n "$m" || test -n "$m0"; } && machine_used=t
896 x*/$submachine) submachine_used=t ;;
906 # If the assembler supports gnu_indirect_function symbol type and the
907 # architecture supports multi-arch, we enable multi-arch by default.
912 test x"$multi_arch" = xdefault && multi_arch=no
915 if test x"$multi_arch" != xno; then
916 AC_DEFINE(USE_MULTIARCH)
920 if test -z "$os_used" && test "$os" != none; then
921 AC_MSG_ERROR(Operating system $os is not supported.)
923 if test -z "$machine_used" && test "$machine" != none; then
924 AC_MSG_ERROR(The $machine is not supported.)
926 if test -z "$submachine_used" && test -n "$submachine"; then
927 AC_MSG_ERROR(The $submachine subspecies of $host_cpu is not supported.)
931 # We have now validated the configuration.
933 # Expand the list of system names into a full list of directories
934 # from each element's parent name and Implies file (if present).
937 while test $# -gt 0; do
941 case " $names " in *" $name "*)
942 # Already in the list.
946 # Report each name as we discover it, so there is no long pause in output.
947 echo $ECHO_N "$name $ECHO_C" >&AS_MESSAGE_FD
949 name_base=`echo $name | sed -e 's@\(.*sysdeps\)/.*@\1@'`
953 *) xsrcdir=$srcdir/ ;;
955 test -n "$enable_debug_configure" &&
956 echo "[DEBUG]: name/Implies $xsrcdir$name/Implies" >&2
958 for implies_file in Implies Implies-before Implies-after; do
959 implies_type=`echo $implies_file | sed s/-/_/`
960 eval ${implies_type}=
961 if test -f $xsrcdir$name/$implies_file; then
962 # Collect more names from the `Implies' file (removing comments).
963 implied_candidate="`sed 's/#.*$//' < $xsrcdir$name/$implies_file`"
964 for x in $implied_candidate; do
966 if test -d $xsrcdir$name_base/$x; then
967 eval "${implies_type}=\"\$${implies_type} \$name_base/\$x\""
972 test -n "$enable_debug_configure" &&
973 echo "[DEBUG]: $name $implies_file $x try() {$try_srcdir}$try" >&2
974 if test $try != $xsrcdir$name_base/$x && test -d $try_srcdir$try;
976 eval "${implies_type}=\"\$${implies_type} \$try\""
979 if test $found = no; then
980 AC_MSG_WARN($name/$implies_file specifies nonexistent $x)
986 # Add NAME to the list of names.
989 # Find the parent of NAME, using the empty string if it has none.
991 parent="`echo $name | sed -n -e 's=/[^/]*$==' -e '/sysdeps$/q' -e p`"
994 test -n "$enable_debug_configure" &&
995 echo "[DEBUG]: $name Implies='$Implies' rest='$*' parent='$parent' \
996 Implies_before='$Implies_before' Implies_after='$Implies_after'" >&2
998 # Add the names implied by NAME, and NAME's parent (if it has one), to
999 # the list of names to be processed (the argument list). We prepend the
1000 # implied names to the list and append the parent. We want implied
1001 # directories to come before further directories inferred from the
1002 # configuration components; this ensures that for sysv4, unix/common
1003 # (implied by unix/sysv/sysv4) comes before unix/sysv (in ostry (here $*)
1005 sysnames="`echo $Implies $* $Implies_before $parent $Implies_after`"
1006 test -n "$sysnames" && set $sysnames
1009 # Add the default directories.
1010 default_sysnames="sysdeps/generic"
1011 sysnames="$names $default_sysnames"
1013 # The other names were emitted during the scan.
1014 AC_MSG_RESULT($default_sysnames)
1016 # if using special system headers, find out the compiler's sekrit
1017 # header directory and add that to the list. NOTE: Only does the right
1018 # thing on a system that doesn't need fixincludes. (Not presently a problem.)
1019 if test -n "$sysheaders"; then
1020 SYSINCLUDES=-nostdinc
1021 for d in include include-fixed; do
1022 i=`$CC -print-file-name="$d"` && test "x$i" != x && test "x$i" != "x$d" &&
1023 SYSINCLUDES="$SYSINCLUDES -isystem $i"
1025 SYSINCLUDES="$SYSINCLUDES \
1026 -isystem `echo $sysheaders | sed 's/:/ -isystem /g'`"
1027 if test -n "$CXX"; then
1029 for cxxheaders in `$CXX -v -S -x c++ /dev/null -o /dev/null 2>&1 \
1030 | sed -n -e '1,/#include/d' -e 's/^ \(\/.*\/[cg]++\)/\1/p'`; do
1031 test "x$cxxheaders" != x &&
1032 CXX_SYSINCLUDES="$CXX_SYSINCLUDES -isystem $cxxheaders"
1036 AC_SUBST(SYSINCLUDES)
1037 AC_SUBST(CXX_SYSINCLUDES)
1039 # Obtain some C++ header file paths. This is used to make a local
1040 # copy of those headers in Makerules.
1041 if test -n "$CXX"; then
1042 find_cxx_header () {
1043 echo "#include <$1>" | $CXX -H -fsyntax-only -x c++ - 2>&1 \
1044 | $AWK '$1 == "."{print $2}'
1046 CXX_CSTDLIB_HEADER="$(find_cxx_header cstdlib)"
1047 CXX_CMATH_HEADER="$(find_cxx_header cmath)"
1048 CXX_BITS_STD_ABS_H="$(find_cxx_header bits/std_abs.h)"
1050 AC_SUBST(CXX_CSTDLIB_HEADER)
1051 AC_SUBST(CXX_CMATH_HEADER)
1052 AC_SUBST(CXX_BITS_STD_ABS_H)
1054 # Test if LD_LIBRARY_PATH contains the notation for the current directory
1055 # since this would lead to problems installing/building glibc.
1056 # LD_LIBRARY_PATH contains the current directory if one of the following
1058 # - one of the terminals (":" and ";") is the first or last sign
1059 # - two terminals occur directly after each other
1060 # - the path contains an element with a dot in it
1061 AC_MSG_CHECKING(LD_LIBRARY_PATH variable)
1063 case ${LD_LIBRARY_PATH} in
1064 [:\;]* | *[:\;] | *[:\;][:\;]* | *[:\;]. | .[:\;]*| . | *[:\;].[:\;]* )
1065 ld_library_path_setting="contains current directory"
1068 ld_library_path_setting="ok"
1072 AC_MSG_RESULT($ld_library_path_setting)
1073 if test "$ld_library_path_setting" != "ok"; then
1075 *** LD_LIBRARY_PATH shouldn't contain the current directory when
1076 *** building glibc. Please change the environment variable
1077 *** and run configure again.])
1080 AC_PATH_PROG(BASH_SHELL, bash, no)
1082 AC_PATH_PROG(PERL, perl, no)
1083 if test "$PERL" != no &&
1084 (eval `$PERL -V:apiversion`; test `expr "$apiversion" \< 5` -ne 0); then
1087 AC_PATH_PROG(INSTALL_INFO, install-info, no,
1088 $PATH:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin)
1090 AC_CACHE_CHECK(for .set assembler directive, libc_cv_asm_set_directive, [dnl
1091 cat > conftest.s <<EOF
1094 .set glibc_conftest_frobozz,foo
1095 .globl glibc_conftest_frobozz
1097 # The alpha-dec-osf1 assembler gives only a warning for `.set'
1098 # (but it doesn't work), so we must do a linking check to be sure.
1099 cat > conftest1.c <<\EOF
1100 extern int glibc_conftest_frobozz;
1101 void _start() { glibc_conftest_frobozz = 1; }
1103 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
1104 -nostartfiles -nostdlib $no_ssp \
1105 -o conftest conftest.s conftest1.c 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then
1106 libc_cv_asm_set_directive=yes
1108 libc_cv_asm_set_directive=no
1111 if test $libc_cv_asm_set_directive = yes; then
1112 AC_DEFINE(HAVE_ASM_SET_DIRECTIVE)
1115 AC_CACHE_CHECK(linker support for protected data symbol,
1116 libc_cv_protected_data,
1117 [cat > conftest.c <<EOF
1118 int bar __attribute__ ((visibility ("protected"))) = 1;
1120 libc_cv_protected_data=no
1121 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -o conftest.so); then
1122 cat > conftest.c <<EOF
1124 int main (void) { return bar; }
1126 if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp conftest.c -o conftest conftest.so); then
1127 libc_cv_protected_data=yes
1132 AC_SUBST(libc_cv_protected_data)
1134 AC_CACHE_CHECK(linker support for INSERT in linker script,
1136 [cat > conftest.c <<EOF
1137 int __attribute__ ((section(".bar"))) bar = 0x12345678;
1138 int test (void) { return bar; }
1140 cat > conftest.t <<EOF
1145 INSERT AFTER .rela.dyn;
1148 if AC_TRY_COMMAND([${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -Wl,-T,conftest.t -o conftest.so]); then
1153 AC_SUBST(libc_cv_insert)
1155 AC_CACHE_CHECK(for broken __attribute__((alias())),
1156 libc_cv_broken_alias_attribute,
1157 [cat > conftest.c <<EOF
1158 extern int foo (int x) __asm ("xyzzy");
1159 int bar (int x) { return x; }
1160 extern __typeof (bar) foo __attribute ((weak, alias ("bar")));
1162 extern __typeof (dfoo) dfoo __asm ("abccb");
1165 libc_cv_broken_alias_attribute=yes
1166 if AC_TRY_COMMAND(${CC-cc} -Werror -S conftest.c -o conftest.s 1>&AS_MESSAGE_LOG_FD); then
1167 if grep 'xyzzy' conftest.s >/dev/null &&
1168 grep 'abccb' conftest.s >/dev/null; then
1169 libc_cv_broken_alias_attribute=no
1172 rm -f conftest.c conftest.s
1174 if test $libc_cv_broken_alias_attribute = yes; then
1175 AC_MSG_ERROR(working alias attribute support required)
1178 AC_CACHE_CHECK(whether to put _rtld_local into .sdata section,
1179 libc_cv_have_sdata_section,
1180 [echo "int i;" > conftest.c
1181 libc_cv_have_sdata_section=no
1182 if ${CC-cc} $LDFLAGS -fPIC -shared -Wl,--verbose conftest.c -o conftest.so 2>&1 \
1183 | grep '\.sdata' >/dev/null; then
1184 libc_cv_have_sdata_section=yes
1186 rm -f conftest.c conftest.so
1188 if test $libc_cv_have_sdata_section = yes; then
1189 AC_DEFINE(HAVE_SDATA_SECTION)
1192 AC_CACHE_CHECK(for libunwind-support in compiler,
1193 libc_cv_cc_with_libunwind, [
1194 cat > conftest.c <<EOF
1195 int main (void) { return 0; }
1197 if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -static -o conftest \
1198 conftest.c -v 2>&1 >/dev/null | grep ' -lunwind ' >/dev/null; then
1199 libc_cv_cc_with_libunwind=yes
1201 libc_cv_cc_with_libunwind=no
1204 AC_SUBST(libc_cv_cc_with_libunwind)
1205 if test $libc_cv_cc_with_libunwind = yes; then
1206 AC_DEFINE(HAVE_CC_WITH_LIBUNWIND)
1210 AC_CACHE_CHECK(whether --noexecstack is desirable for .S files,
1211 libc_cv_as_noexecstack, [dnl
1212 cat > conftest.c <<EOF
1215 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS
1216 -S -o conftest.s conftest.c 1>&AS_MESSAGE_LOG_FD]) \
1217 && grep .note.GNU-stack conftest.s >/dev/null \
1218 && AC_TRY_COMMAND([${CC-cc} $ASFLAGS -Wa,--noexecstack
1219 -c -o conftest.o conftest.s 1>&AS_MESSAGE_LOG_FD])
1221 libc_cv_as_noexecstack=yes
1223 libc_cv_as_noexecstack=no
1226 if test $libc_cv_as_noexecstack = yes; then
1227 ASFLAGS_config="$ASFLAGS_config -Wa,--noexecstack"
1229 AC_SUBST(ASFLAGS_config)
1231 LIBC_LINKER_FEATURE([-z execstack], [-Wl,-z,execstack],
1232 [libc_cv_z_execstack=yes], [libc_cv_z_execstack=no])
1233 AC_SUBST(libc_cv_z_execstack)
1235 LIBC_LINKER_FEATURE([-z start-stop-gc], [-Wl,-z,start-stop-gc],
1236 [libc_cv_z_start_stop_gc=yes], [libc_cv_z_start_stop_gc=no])
1237 LIBC_CONFIG_VAR([have-z-start-stop-gc], [$libc_cv_z_start_stop_gc])
1239 LIBC_LINKER_FEATURE([--depaudit], [-Wl,--depaudit,x],
1240 [libc_cv_depaudit=yes], [libc_cv_depaudit=no])
1241 LIBC_CONFIG_VAR([have-depaudit], [$libc_cv_depaudit])
1243 LIBC_LINKER_FEATURE([-z pack-relative-relocs],
1244 [-Wl,-z,pack-relative-relocs],
1245 [libc_cv_dt_relr=yes], [libc_cv_dt_relr=no])
1246 LIBC_CONFIG_VAR([have-dt-relr], [$libc_cv_dt_relr])
1248 LIBC_LINKER_FEATURE([--no-dynamic-linker],
1249 [-Wl,--no-dynamic-linker],
1250 [libc_cv_no_dynamic_linker=yes],
1251 [libc_cv_no_dynamic_linker=no])
1252 LIBC_CONFIG_VAR([have-no-dynamic-linker], [$libc_cv_no_dynamic_linker])
1254 AC_CACHE_CHECK(for -static-pie, libc_cv_static_pie, [dnl
1255 LIBC_TRY_CC_OPTION([-static-pie],
1256 [libc_cv_static_pie=yes],
1257 [libc_cv_static_pie=no])
1259 LIBC_CONFIG_VAR([have-static-pie], [$libc_cv_static_pie])
1261 AC_CACHE_CHECK(for -fpie, libc_cv_fpie, [dnl
1262 LIBC_TRY_CC_OPTION([-fpie], [libc_cv_fpie=yes], [libc_cv_fpie=no])
1265 AC_SUBST(libc_cv_fpie)
1267 AC_CACHE_CHECK(for GLOB_DAT reloc,
1268 libc_cv_has_glob_dat, [dnl
1269 cat > conftest.c <<EOF
1271 int foo (void) { return mumble; }
1273 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS
1274 -fPIC -shared -o conftest.so conftest.c
1275 -nostdlib -nostartfiles $no_ssp
1276 1>&AS_MESSAGE_LOG_FD])
1278 dnl look for GLOB_DAT relocation.
1279 if $READELF -rW conftest.so | grep '_GLOB_DAT' > /dev/null; then
1280 libc_cv_has_glob_dat=yes
1282 libc_cv_has_glob_dat=no
1285 libc_cv_has_glob_dat=no
1288 AC_SUBST(libc_cv_has_glob_dat)
1290 AC_CACHE_CHECK([for -mtls-dialect=gnu2], libc_cv_mtls_dialect_gnu2,
1292 cat > conftest.c <<EOF
1299 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -fPIC -mtls-dialect=gnu2 -nostdlib -nostartfiles
1300 -shared conftest.c -o conftest 1>&AS_MESSAGE_LOG_FD])
1302 libc_cv_mtls_dialect_gnu2=yes
1304 libc_cv_mtls_dialect_gnu2=no
1307 AC_SUBST(libc_cv_mtls_dialect_gnu2)
1308 LIBC_CONFIG_VAR([have-mtls-dialect-gnu2], [$libc_cv_mtls_dialect_gnu2])
1310 dnl clang emits an warning for a double alias redirection, to warn the
1311 dnl original symbol is sed even when weak definition overrides it.
1312 dnl It is a usual pattern for weak_alias, where multiple alias point to
1314 AC_CACHE_CHECK([if -Wno-ignored-attributes is required for aliases],
1315 libc_cv_wno_ignored_attributes, [dnl
1316 cat > conftest.c <<EOF
1320 extern __typeof (__foo) foo __attribute__ ((weak, alias ("__foo")));
1321 extern __typeof (__foo) bar __attribute__ ((weak, alias ("foo")));
1323 libc_cv_wno_ignored_attributes=""
1324 if ! AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -Werror -c conftest.c])
1326 libc_cv_wno_ignored_attributes="-Wno-ignored-attributes"
1329 LIBC_CONFIG_VAR([config-cflags-wno-ignored-attributes],
1330 [$libc_cv_wno_ignored_attributes])
1332 AC_CACHE_CHECK(whether cc puts quotes around section names,
1333 libc_cv_have_section_quotes,
1334 [cat > conftest.c <<EOF
1335 static const int foo
1336 __attribute__ ((section ("bar"))) = 1;
1338 if ${CC-cc} -S conftest.c -o conftest.s; then
1339 if grep '\.section.*"bar"' conftest.s >/dev/null; then
1340 libc_cv_have_section_quotes=yes
1342 libc_cv_have_section_quotes=no
1345 libc_cv_have_section_quotes=unknown
1347 rm -f conftest.{c,s}
1349 if test $libc_cv_have_section_quotes = yes; then
1350 AC_DEFINE(HAVE_SECTION_QUOTES)
1353 AC_CACHE_CHECK(for __builtin_memset, libc_cv_gcc_builtin_memset, [dnl
1354 cat > conftest.c <<\EOF
1357 __builtin_memset (x, 0, 1000);
1361 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "memset" > /dev/null]);
1363 libc_cv_gcc_builtin_memset=no
1365 libc_cv_gcc_builtin_memset=yes
1368 if test "$libc_cv_gcc_builtin_memset" = yes ; then
1369 AC_DEFINE(HAVE_BUILTIN_MEMSET)
1372 AC_CACHE_CHECK(for redirection of built-in functions, libc_cv_gcc_builtin_redirection, [dnl
1373 cat > conftest.c <<\EOF
1374 extern char *strstr (const char *, const char *) __asm ("my_strstr");
1375 char *foo (const char *a, const char *b)
1377 return __builtin_strstr (a, b);
1381 if AC_TRY_COMMAND([${CC-cc} -O3 -S conftest.c -o - | grep -F "my_strstr" > /dev/null]);
1383 libc_cv_gcc_builtin_redirection=yes
1385 libc_cv_gcc_builtin_redirection=no
1388 if test "$libc_cv_gcc_builtin_redirection" = no; then
1389 AC_MSG_ERROR([support for the symbol redirection needed])
1392 dnl Determine how to disable generation of FMA instructions.
1393 AC_CACHE_CHECK([for compiler option to disable generation of FMA instructions],
1394 libc_cv_cc_nofma, [dnl
1396 for opt in -ffp-contract=off -mno-fused-madd; do
1397 LIBC_TRY_CC_OPTION([$opt], [libc_cv_cc_nofma=$opt; break])
1399 AC_SUBST(libc_cv_cc_nofma)
1401 if test -n "$submachine"; then
1402 AC_CACHE_CHECK([for compiler option for CPU variant],
1403 libc_cv_cc_submachine, [dnl
1404 libc_cv_cc_submachine=no
1405 for opt in "-march=$submachine" "-mcpu=$submachine"; do
1406 LIBC_TRY_CC_OPTION([$opt], [
1407 libc_cv_cc_submachine="$opt"
1410 if test "x$libc_cv_cc_submachine" = xno; then
1411 AC_MSG_ERROR([${CC-cc} does not support $submachine])
1414 AC_SUBST(libc_cv_cc_submachine)
1416 dnl Determine if compiler supports -fsignaling-nans
1417 AC_CACHE_CHECK([for compiler option that -fsignaling-nans],
1418 libc_cv_cc_signaling_nans, [dnl
1419 LIBC_TRY_CC_OPTION([-Werror -fsignaling-nans],
1420 [libc_cv_cc_signaling_nans=-fsignaling-nans],
1421 [libc_cv_cc_signaling_nans=])
1423 LIBC_CONFIG_VAR([config-cflags-signaling-nans],
1424 [$libc_cv_cc_signaling_nans])
1426 AC_CACHE_CHECK(if $CC accepts -fno-tree-loop-distribute-patterns with \
1427 __attribute__ ((__optimize__)), libc_cv_cc_loop_to_function, [dnl
1428 cat > conftest.c <<EOF
1430 __attribute__ ((__optimize__ ("-fno-tree-loop-distribute-patterns")))
1433 libc_cv_cc_loop_to_function=no
1434 if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -c conftest.c])
1436 libc_cv_cc_loop_to_function=yes
1439 if test $libc_cv_cc_loop_to_function = yes; then
1440 AC_DEFINE(HAVE_CC_INHIBIT_LOOP_TO_LIBCALL)
1442 AC_SUBST(libc_cv_cc_loop_to_function)
1444 dnl Check whether we have the gd library available.
1445 AC_MSG_CHECKING(for libgd)
1446 if test "$with_gd" != "no"; then
1447 old_CFLAGS="$CFLAGS"
1448 CFLAGS="$CFLAGS $libgd_include"
1449 old_LDFLAGS="$LDFLAGS"
1450 LDFLAGS="$LDFLAGS $libgd_ldflags"
1452 LIBS="$LIBS -lgd -lpng -lz -lm"
1453 AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <gd.h>]], [[gdImagePng (0, 0)]])],
1454 [LIBGD=yes], [LIBGD=no])
1455 CFLAGS="$old_CFLAGS"
1456 LDFLAGS="$old_LDFLAGS"
1461 AC_MSG_RESULT($LIBGD)
1465 if test x$with_selinux = xno ; then
1468 # See if we have the SELinux library
1469 AC_CHECK_LIB(selinux, is_selinux_enabled,
1470 have_selinux=yes, have_selinux=no)
1471 if test x$with_selinux = xyes ; then
1472 if test x$have_selinux = xno ; then
1473 AC_MSG_ERROR([SELinux explicitly required, but SELinux library not found])
1477 # Check if we're building with SELinux support.
1478 if test "x$have_selinux" = xyes; then
1479 AC_DEFINE(HAVE_SELINUX, 1, [SELinux support])
1481 # See if we have the libaudit library
1482 AC_CHECK_LIB(audit, audit_log_user_avc_message,
1483 have_libaudit=yes, have_libaudit=no)
1484 if test "x$have_libaudit" = xyes; then
1485 AC_DEFINE(HAVE_LIBAUDIT, 1, [SELinux libaudit support])
1487 AC_SUBST(have_libaudit)
1489 # See if we have the libcap library
1490 AC_CHECK_LIB(cap, cap_init, have_libcap=yes, have_libcap=no)
1491 if test "x$have_libcap" = xyes; then
1492 AC_DEFINE(HAVE_LIBCAP, 1, [SELinux libcap support])
1494 AC_SUBST(have_libcap)
1496 AC_SUBST(have_selinux)
1498 dnl Check if we support the requested _FORTIFY_SOURCE level
1499 dnl If not, then don't use it.
1500 dnl Note that _FORTIFY_SOURCE may have been set through FLAGS too.
1501 dnl _FORTIFY_SOURCE value will be selectively disabled for function that can't
1503 no_fortify_source="-Wp,-U_FORTIFY_SOURCE"
1504 fortify_source="${no_fortify_source}"
1506 AC_CACHE_CHECK([for maximum supported _FORTIFY_SOURCE level],
1507 [libc_cv_supported_fortify_source], [
1508 AC_LINK_IFELSE([AC_LANG_PROGRAM([], [__builtin_dynamic_object_size("", 0)])],
1509 [libc_cv_supported_fortify_source=3],
1510 [libc_cv_supported_fortify_source=2])
1513 AS_CASE([$enable_fortify_source],
1514 [yes], [libc_cv_fortify_source=yes enable_fortify_source=$libc_cv_supported_fortify_source],
1515 [1|2], [libc_cv_fortify_source=yes],
1516 [3], [AS_IF([test $libc_cv_supported_fortify_source = 3],
1517 [libc_cv_fortify_source=yes],
1518 [AC_MSG_ERROR([Compiler doesn't provide necessary support for _FORTIFY_SOURCE=3])])],
1519 [libc_cv_fortify_source=no])
1521 AS_IF([test "$libc_cv_fortify_source" = yes],
1522 [fortify_source="${fortify_source},-D_FORTIFY_SOURCE=${enable_fortify_source}"]
1525 AC_SUBST(enable_fortify_source)
1526 AC_SUBST(libc_cv_fortify_source)
1527 AC_SUBST(no_fortify_source)
1528 AC_SUBST(fortify_source)
1529 LIBC_CONFIG_VAR([supported-fortify], [$libc_cv_supported_fortify_source])
1531 dnl Starting with binutils 2.35, GAS can attach multiple symbol versions
1532 dnl to one symbol (PR 23840).
1533 AC_CACHE_CHECK(whether the assembler requires one version per symbol,
1534 libc_cv_symver_needs_alias, [dnl
1535 cat > conftest.s <<EOF
1539 .symver testfunc, testfunc1@VERSION1
1540 .symver testfunc, testfunc1@VERSION2
1542 libc_cv_symver_needs_alias=no
1543 if ${CC-cc} $ASFLAGS -c conftest.s 2>&AS_MESSAGE_LOG_FD; then
1544 libc_cv_symver_needs_alias=no
1546 libc_cv_symver_needs_alias=yes
1550 if test "$libc_cv_symver_needs_alias" = yes; then
1551 AC_DEFINE(SYMVER_NEEDS_ALIAS)
1554 AC_CACHE_CHECK(for __builtin_trap with no external dependencies,
1555 libc_cv_builtin_trap, [dnl
1556 libc_cv_builtin_trap=no
1557 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[__builtin_trap ()]])],[
1558 libc_undefs=`$NM -u conftest.o |
1559 LC_ALL=C $AWK '$1 == "U" { print $2 | "sort -u"; next } { exit(1) }' \
1560 2>&AS_MESSAGE_LOG_FD` || {
1561 AC_MSG_ERROR([confusing output from $NM -u])
1563 echo >&AS_MESSAGE_LOG_FD "libc_undefs='$libc_undefs'"
1564 if test -z "$libc_undefs"; then
1565 libc_cv_builtin_trap=yes
1567 if test $libc_cv_builtin_trap = yes; then
1568 AC_DEFINE([HAVE_BUILTIN_TRAP])
1571 dnl C++ feature tests.
1574 AC_CACHE_CHECK([whether the C++ compiler supports thread_local],
1575 libc_cv_cxx_thread_local, [
1576 old_CXXFLAGS="$CXXFLAGS"
1577 CXXFLAGS="$CXXFLAGS -std=gnu++11"
1578 AC_COMPILE_IFELSE([AC_LANG_SOURCE([
1581 // Compiler support.
1588 S * get () { return &s; }
1590 // libstdc++ support.
1591 #ifndef _GLIBCXX_HAVE___CXA_THREAD_ATEXIT_IMPL
1592 #error __cxa_thread_atexit_impl not supported
1595 [libc_cv_cxx_thread_local=yes],
1596 [libc_cv_cxx_thread_local=no])
1597 CXXFLAGS="$old_CXXFLAGS"
1599 AC_SUBST(libc_cv_cxx_thread_local)
1602 dnl End of C++ feature tests.
1604 ### End of automated tests.
1605 ### Now run sysdeps configure fragments.
1607 # They also can set these variables.
1609 ldd_rewrite_script=no
1610 libc_cv_sysconfdir=$sysconfdir
1611 libc_cv_localstatedir=$localstatedir
1612 libc_cv_gcc_unwind_find_fde=no
1616 # Iterate over all the sysdep directories we will use, running their
1617 # configure fragments.
1618 for dir in $sysnames; do
1621 *) dest=$srcdir/$dir ;;
1623 if test -r $dest/configure; then
1624 AC_MSG_RESULT(running configure fragment for $dir)
1629 if test x"$build_mathvec" = xnotset; then
1632 LIBC_CONFIG_VAR([build-mathvec], [$build_mathvec])
1634 AC_SUBST(libc_extra_cflags)
1635 AC_SUBST(libc_extra_cppflags)
1637 if test x$libc_cv_gcc_unwind_find_fde = xyes; then
1638 AC_DEFINE(EXPORT_UNWIND_FIND_FDE)
1640 AC_SUBST(libc_cv_gcc_unwind_find_fde)
1642 # A sysdeps configure fragment can reset this if IFUNC is not actually
1643 # usable even though the assembler knows how to generate the symbol type.
1644 if test x"$libc_cv_ld_gnu_indirect_function" = xyes; then
1645 AC_DEFINE(HAVE_IFUNC)
1647 LIBC_CONFIG_VAR([have-ifunc], [$libc_cv_ld_gnu_indirect_function])
1649 if test x"$libc_cv_gcc_indirect_function" = xyes; then
1650 AC_DEFINE(HAVE_GCC_IFUNC)
1652 LIBC_CONFIG_VAR([have-gcc-ifunc], [$libc_cv_gcc_indirect_function])
1654 # This is far from the AC_ARG_ENABLE that sets it so that a sysdeps
1655 # configure fragment can override the value to prevent this AC_DEFINE.
1657 if test "x$use_nscd" != xno; then
1658 AC_DEFINE([USE_NSCD])
1660 if test "x$build_nscd" = xdefault; then
1661 build_nscd=$use_nscd
1664 AC_SUBST(libc_cv_slibdir)
1665 AC_SUBST(libc_cv_rtlddir)
1666 AC_SUBST(libc_cv_complocaledir)
1667 AC_SUBST(libc_cv_sysconfdir)
1668 AC_SUBST(libc_cv_localstatedir)
1669 AC_SUBST(libc_cv_rootsbindir)
1671 if test x$use_ldconfig = xyes; then
1672 AC_DEFINE(USE_LDCONFIG)
1674 AC_SUBST(use_ldconfig)
1675 AC_SUBST(ldd_rewrite_script)
1680 AC_CACHE_CHECK([whether -fPIC is default], libc_cv_pic_default,
1681 [libc_cv_pic_default=yes
1682 cat > conftest.c <<EOF
1683 #if defined __PIC__ || defined __pic__ || defined PIC || defined pic
1684 # error PIC is default.
1687 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1688 libc_cv_pic_default=no
1691 LIBC_CONFIG_VAR([build-pic-default], [$libc_cv_pic_default])
1693 AC_CACHE_CHECK([whether -fPIE is default], libc_cv_cc_pie_default,
1694 [libc_cv_cc_pie_default=yes
1695 cat > conftest.c <<EOF
1696 #if defined __PIE__ || defined __pie__ || defined PIE || defined pie
1697 # error PIE is default.
1700 if eval "${CC-cc} -S conftest.c 2>&AS_MESSAGE_LOG_FD 1>&AS_MESSAGE_LOG_FD"; then
1701 libc_cv_cc_pie_default=no
1704 LIBC_CONFIG_VAR([cc-pie-default], [$libc_cv_cc_pie_default])
1706 AC_MSG_CHECKING(if we can build programs as PIE)
1707 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#ifdef PIE_UNSUPPORTED
1708 # error PIE is not supported
1709 #endif]])], [libc_cv_pie_supported=yes], [libc_cv_pie_supported=no])
1710 AC_MSG_RESULT($libc_cv_pie_supported)
1711 # Disable build-pie-default if target does not support it or glibc is
1712 # configured with --disable-default-pie.
1713 if test "x$default_pie" = xno; then
1714 build_pie_default=no
1716 build_pie_default=$libc_cv_pie_supported
1718 LIBC_CONFIG_VAR([build-pie-default], [$build_pie_default])
1720 AC_MSG_CHECKING(if we can build static PIE programs)
1721 libc_cv_static_pie_supported=$libc_cv_pie_supported
1722 if test "x$libc_cv_pie_supported" != xno \
1723 -a "$libc_cv_no_dynamic_linker" = yes; then
1724 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#ifndef SUPPORT_STATIC_PIE
1725 # error static PIE is not supported
1726 #endif]])], [libc_cv_static_pie_supported=yes],
1727 [libc_cv_static_pie_supported=no])
1729 AC_MSG_RESULT($libc_cv_static_pie_supported)
1731 # Enable static-pie only if it is available and glibc isn't configured
1732 # with --disable-default-pie.
1733 if test "x$default_pie" = xno; then
1734 libc_cv_static_pie=no
1736 libc_cv_static_pie=$libc_cv_static_pie_supported
1738 if test "$libc_cv_static_pie" = "yes"; then
1739 AC_DEFINE(ENABLE_STATIC_PIE)
1741 LIBC_CONFIG_VAR([enable-static-pie], [$libc_cv_static_pie])
1743 # Set the `multidir' variable by grabbing the variable from the compiler.
1744 # We do it once and save the result in a generated makefile.
1745 libc_cv_multidir=`${CC-cc} $CFLAGS $CPPFLAGS -print-multi-directory`
1746 AC_SUBST(libc_cv_multidir)
1749 AC_SUBST(static_nss)
1753 dnl See sysdeps/mach/configure.ac for this variable.
1754 AC_SUBST(mach_interface_list)
1756 VERSION=`sed -n -e 's/^#define VERSION "\([^"]*\)"/\1/p' < $srcdir/version.h`
1757 RELEASE=`sed -n -e 's/^#define RELEASE "\([^"]*\)"/\1/p' < $srcdir/version.h`
1761 if test "$pthread_in_libc" = yes; then
1762 AC_DEFINE(PTHREAD_IN_LIBC)
1764 AC_SUBST(pthread_in_libc)
1766 AC_CONFIG_FILES([config.make Makefile])
1767 AC_CONFIG_COMMANDS([default],[[
1768 case $CONFIG_FILES in *config.make*)
1769 echo "$config_vars" >> config.make;;
1771 test -d bits || mkdir bits]],[[config_vars='$config_vars']])