diff --git a/config.h.in b/config.h.in index 831eca2fe1..67169e5d01 100644 --- a/config.h.in +++ b/config.h.in @@ -109,6 +109,9 @@ /* AArch64 big endian ABI */ #undef HAVE_AARCH64_BE +/* AArch64 BTI support enabled. */ +#define HAVE_AARCH64_BTI 0 + /* C-SKY ABI version. */ #undef CSKYABI diff --git a/sysdeps/aarch64/configure b/sysdeps/aarch64/configure index 5bd355a691..70477a7fa5 100644 --- a/sysdeps/aarch64/configure +++ b/sysdeps/aarch64/configure @@ -172,3 +172,45 @@ else config_vars="$config_vars default-abi = lp64" fi + +# Only consider BTI supported if -mbranch-protection=bti is +# on by default in the compiler and the linker produces +# binaries with GNU property notes in PT_GNU_PROPERTY segment. +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for BTI support" >&5 +$as_echo_n "checking for BTI support... " >&6; } +if ${libc_cv_aarch64_bti+:} false; then : + $as_echo_n "(cached) " >&6 +else + cat > conftest.c <&5 + (eval $ac_try) 2>&5 + ac_status=$? + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5 + test $ac_status = 0; }; } \ + && { ac_try='$READELF -lW conftest.so | grep -q GNU_PROPERTY' + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5 + (eval $ac_try) 2>&5 + ac_status=$? + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5 + test $ac_status = 0; }; } \ + && { ac_try='$READELF -nW conftest.so | grep -q "NT_GNU_PROPERTY_TYPE_0.*AArch64 feature:.* BTI"' + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5 + (eval $ac_try) 2>&5 + ac_status=$? + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5 + test $ac_status = 0; }; } + then + libc_cv_aarch64_bti=yes + fi + rm -rf conftest.* +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_aarch64_bti" >&5 +$as_echo "$libc_cv_aarch64_bti" >&6; } +if test $libc_cv_aarch64_bti = yes; then + $as_echo "#define HAVE_AARCH64_BTI 1" >>confdefs.h + +fi diff --git a/sysdeps/aarch64/configure.ac b/sysdeps/aarch64/configure.ac index 7851dd4dac..798f494740 100644 --- a/sysdeps/aarch64/configure.ac +++ b/sysdeps/aarch64/configure.ac @@ -20,3 +20,22 @@ if test $libc_cv_aarch64_be = yes; then else LIBC_CONFIG_VAR([default-abi], [lp64]) fi + +# Only consider BTI supported if -mbranch-protection=bti is +# on by default in the compiler and the linker produces +# binaries with GNU property notes in PT_GNU_PROPERTY segment. +AC_CACHE_CHECK([for BTI support], [libc_cv_aarch64_bti], [dnl + cat > conftest.c <