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|
GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory.
# Local configure fragment for sysdeps/x86.
if test $enable_cet != no; then
# Check if CET can be enabled.
AC_CACHE_CHECK(whether CET can be enabled,
libc_cv_x86_cet_available, [dnl
cat > conftest.c <<EOF
#if !defined __CET__ || __CET__ != 3
# error CET isn't available.
#endif
EOF
if AC_TRY_COMMAND(${CC-cc} -c $CFLAGS -fcf-protection -include cet.h conftest.c 1>&AS_MESSAGE_LOG_FD); then
libc_cv_x86_cet_available=yes
else
libc_cv_x86_cet_available=no
fi
rm -rf conftest*])
if test $libc_cv_x86_cet_available != yes; then
AC_MSG_ERROR([$CC doesn't support CET])
fi
fi
if test $enable_cet != no; then
# Check if assembler supports CET.
AC_CACHE_CHECK(whether $AS supports CET,
libc_cv_x86_cet_as, [dnl
cat > conftest.s <<EOF
incsspd %ecx
EOF
if AC_TRY_COMMAND(${CC-cc} -c $CFLAGS conftest.s -o conftest.o 1>&AS_MESSAGE_LOG_FD); then
libc_cv_x86_cet_as=yes
else
libc_cv_x86_cet_as=no
fi
rm -rf conftest*])
if test $libc_cv_x86_cet_as = no; then
AC_MSG_ERROR([$AS doesn't support CET])
fi
fi
if test $enable_cet = yes; then
AC_DEFINE(DEFAULT_DL_X86_CET_CONTROL, cet_elf_property)
elif test $enable_cet = permissive; then
AC_DEFINE(DEFAULT_DL_X86_CET_CONTROL, cet_permissive)
fi
LIBC_CONFIG_VAR([enable-cet], [$enable_cet])
# Check if linker supports x86 ISA level.
AC_CACHE_CHECK([for linker x86 ISA level support],
libc_cv_include_x86_isa_level, [dnl
cat > conftest1.S <<EOF
#ifdef __LP64__
# define P2ALIGN 3
#else
# define P2ALIGN 2
#endif
.section ".note.gnu.property", "a"
.p2align P2ALIGN
.long 1f - 0f /* name length. */
.long 4f - 1f /* data length. */
/* NT_GNU_PROPERTY_TYPE_0 */
.long 5 /* note type. */
0:
.asciz "GNU" /* vendor name. */
1:
.p2align P2ALIGN
/* GNU_PROPERTY_X86_ISA_1_NEEDED */
.long 0xc0008002 /* pr_type. */
.long 3f - 2f /* pr_datasz. */
2:
.long 0x1
3:
.p2align P2ALIGN
4:
EOF
cat > conftest2.S <<EOF
#ifdef __LP64__
# define P2ALIGN 3
#else
# define P2ALIGN 2
#endif
.section ".note.gnu.property", "a"
.p2align P2ALIGN
.long 1f - 0f /* name length. */
.long 4f - 1f /* data length. */
/* NT_GNU_PROPERTY_TYPE_0 */
.long 5 /* note type. */
0:
.asciz "GNU" /* vendor name. */
1:
.p2align P2ALIGN
/* GNU_PROPERTY_X86_ISA_1_NEEDED */
.long 0xc0008002 /* pr_type. */
.long 3f - 2f /* pr_datasz. */
2:
.long 0x2
3:
.p2align P2ALIGN
4:
EOF
libc_cv_include_x86_isa_level=no
if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS -nostartfiles -nostdlib -r -o conftest conftest1.S conftest2.S); then
count=`LC_ALL=C $READELF -n conftest | grep NT_GNU_PROPERTY_TYPE_0 | wc -l`
if test "$count" = 1; then
libc_cv_include_x86_isa_level=yes
fi
fi
rm -f conftest*])
if test $libc_cv_include_x86_isa_level = yes; then
AC_DEFINE(INCLUDE_X86_ISA_LEVEL)
AC_CACHE_CHECK([for LAHF/SAHF instruction support],
libc_cv_have_x86_lahf_sahf, [dnl
libc_cv_have_x86_lahf_sahf=no
if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS -fverbose-asm -S -o - -x c /dev/null) | grep -qE '(-msahf\b|-march=x86-64-v)'; then
libc_cv_have_x86_lahf_sahf=yes
fi])
if test $libc_cv_have_x86_lahf_sahf = yes; then
AC_DEFINE(HAVE_X86_LAHF_SAHF)
fi
AC_CACHE_CHECK([for MOVBE instruction support],
libc_cv_have_x86_movbe, [dnl
libc_cv_have_x86_movbe=no
if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS -fverbose-asm -S -o - -x c /dev/null) | grep -qE '(-mmovbe\b|-march=x86-64-v(@<:@3-9@:>@|@<:@1-9@:>@@<:@0-9@:>@))'; then
libc_cv_have_x86_movbe=yes
fi])
if test $libc_cv_have_x86_movbe = yes; then
AC_DEFINE(HAVE_X86_MOVBE)
fi
fi
LIBC_CONFIG_VAR([enable-x86-isa-level], [$libc_cv_include_x86_isa_level])
dnl It is always possible to access static and hidden symbols in an
dnl position independent way.
AC_DEFINE(PI_STATIC_AND_HIDDEN)
dnl Static PIE is supported.
AC_DEFINE(SUPPORT_STATIC_PIE)
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