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GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory.
# Local configure fragment for sysdeps/arm.
dnl It is always possible to access static and hidden symbols in an
dnl position independent way.
dnl NOTE: This feature was added by the GCC TLS patches. We should test for
dnl it. Until we do, don't define it.
#AC_DEFINE(PI_STATIC_AND_HIDDEN)
# We check to see if the compiler and flags are
# selecting the hard-float ABI and if they are then
# we set libc_cv_arm_pcs_vfp to yes which causes
# HAVE_ARM_PCS_VFP to be defined in config.h and
# in include/libc-symbols.h and thus available to
# shlib-versions to select the appropriate name for
# the dynamic linker via %ifdef.
AC_CACHE_CHECK([whether the compiler is using the ARM hard-float ABI],
[libc_cv_arm_pcs_vfp],
[AC_EGREP_CPP(yes,[#ifdef __ARM_PCS_VFP
yes
#endif
], libc_cv_arm_pcs_vfp=yes, libc_cv_arm_pcs_vfp=no)])
if test $libc_cv_arm_pcs_vfp = yes; then
AC_DEFINE(HAVE_ARM_PCS_VFP)
LIBC_CONFIG_VAR([default-abi], [hard])
else
LIBC_CONFIG_VAR([default-abi], [soft])
fi
AC_CACHE_CHECK([whether the build tools support the GNU descriptor TLS scheme],
[libc_cv_arm_tls_desc],
[old_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS -mtls-dialect=gnu2"
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([asm (".word\tfoo(tlsdesc)");], [])],
[libc_cv_arm_tls_desc=yes], [libc_cv_arm_tls_desc=no])
CFLAGS="$old_CFLAGS"])
if test $libc_cv_arm_tls_desc = yes; then
LIBC_CONFIG_VAR([have-arm-tls-desc], [yes])
else
LIBC_CONFIG_VAR([have-arm-tls-desc], [no])
fi
AC_CACHE_CHECK([whether PC-relative relocs in movw/movt work properly],
libc_cv_arm_pcrel_movw, [
cat > conftest.s <<\EOF
.syntax unified
.arm
.arch armv7-a
.text
.globl foo
.type foo,%function
foo: movw r0, #:lower16:symbol - 1f - 8
movt r0, #:upper16:symbol - 1f - 8
1: add r0, pc
@ And now a case with a local symbol.
movw r0, #:lower16:3f - 2f - 8
movt r0, #:upper16:3f - 2f - 8
2: add r0, pc
bx lr
.data
.globl symbol
.hidden symbol
symbol: .long 23
3: .long 17
EOF
libc_cv_arm_pcrel_movw=no
${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \
-nostartfiles -nostdlib -shared \
-o conftest.so conftest.s 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD &&
LC_ALL=C $READELF -dr conftest.so > conftest.dr 2>&AS_MESSAGE_LOG_FD &&
{
cat conftest.dr 1>&AS_MESSAGE_LOG_FD
fgrep 'TEXTREL
R_ARM_NONE' conftest.dr > /dev/null || libc_cv_arm_pcrel_movw=yes
}
rm -f conftest*])
if test $libc_cv_arm_pcrel_movw = yes; then
AC_DEFINE([ARM_PCREL_MOVW_OK])
fi
libc_cv_gcc_unwind_find_fde=no
# Remove -fno-unwind-tables that was added in sysdeps/arm/preconfigure.ac.
CFLAGS=${CFLAGS% -fno-unwind-tables}
dnl The normal configure check for gcc -fexecptions fails because it can't
dnl find __aeabi_unwind_cpp_pr0. Work around this here; our GCC definitely
dnl has -fexceptions.
libc_cv_gcc_exceptions=yes
exceptions=-fexceptions
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