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. This has been true since GCC 4.1, dnl which is older than the minimum version required to build libc. 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