diff options
| author | Fangrui Song <maskray@google.com> | 2021-07-08 14:26:22 -0700 |
|---|---|---|
| committer | Fangrui Song <i@maskray.me> | 2021-08-27 17:26:06 -0700 |
| commit | a21d58a0dcd816bd97b9de328ad1870cc7098d9b (patch) | |
| tree | f9b99f3f585691be44ae52cdd3e0c027f632aec2 | |
| parent | 2d20ffe431ddd299b50ba250fce43285b9617d31 (diff) | |
| download | glibc-a21d58a0dcd816bd97b9de328ad1870cc7098d9b.tar.gz | |
x86_64: Remove unneeded static PIE check for undefined weak diagnostic
https://sourceware.org/bugzilla/show_bug.cgi?id=21782 dropped an ld
diagnostic for R_X86_64_PC32 referencing an undefined weak symbol in
-pie links. Arguably keeping the diagnostic like other ports is more
correct, since statically resolving movl foo(%rip), %eax to the
link-time zero address produces a corrupted output.
It turns out that --enable-static-pie builds do not depend on the ld
behavior. GCC generates GOT indirection for weak declarations for
-fPIE/-fPIC, so what ld does with the PC-relative relocation doesn't
really matter.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
| -rwxr-xr-x[-rw-r--r--] | sysdeps/x86_64/configure | 33 | ||||
| -rw-r--r-- | sysdeps/x86_64/configure.ac | 25 |
2 files changed, 0 insertions, 58 deletions
diff --git a/sysdeps/x86_64/configure b/sysdeps/x86_64/configure index 8674d14569..efef46b1b7 100644..100755 --- a/sysdeps/x86_64/configure +++ b/sysdeps/x86_64/configure @@ -85,39 +85,6 @@ if test x"$build_mathvec" = xnotset; then build_mathvec=yes fi -if test "$static_pie" = yes; then - { $as_echo "$as_me:${as_lineno-$LINENO}: checking for linker static PIE support" >&5 -$as_echo_n "checking for linker static PIE support... " >&6; } -if ${libc_cv_ld_static_pie+:} false; then : - $as_echo_n "(cached) " >&6 -else - cat > conftest.s <<\EOF - .text - .global _start - .weak foo -_start: - leaq foo(%rip), %rax -EOF - libc_cv_pie_option="-Wl,-pie" - if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp $libc_cv_pie_option -o conftest conftest.s 1>&5' - { { eval echo "\"\$as_me\":${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_ld_static_pie=yes - else - libc_cv_ld_static_pie=no - fi -rm -f conftest* -fi -{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_ld_static_pie" >&5 -$as_echo "$libc_cv_ld_static_pie" >&6; } - if test "$libc_cv_ld_static_pie" != yes; then - as_fn_error $? "linker support for static PIE needed" "$LINENO" 5 - fi -fi - $as_echo "#define PI_STATIC_AND_HIDDEN 1" >>confdefs.h diff --git a/sysdeps/x86_64/configure.ac b/sysdeps/x86_64/configure.ac index b7d2c0124f..fa86e953ee 100644 --- a/sysdeps/x86_64/configure.ac +++ b/sysdeps/x86_64/configure.ac @@ -44,31 +44,6 @@ if test x"$build_mathvec" = xnotset; then build_mathvec=yes fi -dnl Check if linker supports static PIE with the fix for -dnl -dnl https://sourceware.org/bugzilla/show_bug.cgi?id=21782 -dnl -if test "$static_pie" = yes; then - AC_CACHE_CHECK(for linker static PIE support, libc_cv_ld_static_pie, [dnl -cat > conftest.s <<\EOF - .text - .global _start - .weak foo -_start: - leaq foo(%rip), %rax -EOF - libc_cv_pie_option="-Wl,-pie" - if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp $libc_cv_pie_option -o conftest conftest.s 1>&AS_MESSAGE_LOG_FD); then - libc_cv_ld_static_pie=yes - else - libc_cv_ld_static_pie=no - fi -rm -f conftest*]) - if test "$libc_cv_ld_static_pie" != yes; then - AC_MSG_ERROR([linker support for static PIE needed]) - fi -fi - dnl It is always possible to access static and hidden symbols in an dnl position independent way. AC_DEFINE(PI_STATIC_AND_HIDDEN) |