diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rwxr-xr-x | configure | 26 | ||||
| -rw-r--r-- | configure.ac | 23 |
3 files changed, 44 insertions, 11 deletions
@@ -1,3 +1,9 @@ +2014-08-12 Mike Frysinger <vapier@gentoo.org> + + * configure.ac: Change __ehdr_start code to dereference the struct. + Run readelf on the output to look for relocations. + * configure: Regenerated. + 2014-08-12 Joseph Myers <joseph@codesourcery.com> [BZ #17261] @@ -6965,8 +6965,11 @@ if test $libc_cv_predef_stack_protector = yes; then fi libc_extra_cppflags= -{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the linker provides __ehdr_start" >&5 -$as_echo_n "checking whether the linker provides __ehdr_start... " >&6; } +# Some linkers on some architectures support __ehdr_start but with +# bugs. Make sure usage of it does not create relocations in the +# output (as the linker should resolve them all for us). +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the linker provides working __ehdr_start" >&5 +$as_echo_n "checking whether the linker provides working __ehdr_start... " >&6; } if ${libc_cv_ehdr_start+:} false; then : $as_echo_n "(cached) " >&6 else @@ -6980,12 +6983,20 @@ LIBS= cat confdefs.h - <<_ACEOF >conftest.$ac_ext /* end confdefs.h. */ -extern const char __ehdr_start __attribute__ ((visibility ("hidden"))); -const char *ehdr (void) { return &__ehdr_start; } +typedef struct { + char foo; + long val; +} Ehdr; +extern const Ehdr __ehdr_start __attribute__ ((visibility ("hidden"))); +long ehdr (void) { return __ehdr_start.val; } _ACEOF if ac_fn_c_try_link "$LINENO"; then : - libc_cv_ehdr_start=yes + if $READELF -r conftest | fgrep __ehdr_start >/dev/null; then + libc_cv_ehdr_start=broken + else + libc_cv_ehdr_start=yes + fi else libc_cv_ehdr_start=no fi @@ -6998,9 +7009,12 @@ LIBS="$old_LIBS" fi { $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_ehdr_start" >&5 $as_echo "$libc_cv_ehdr_start" >&6; } -if test $libc_cv_ehdr_start = yes; then +if test "$libc_cv_ehdr_start" = yes; then $as_echo "#define HAVE_EHDR_START 1" >>confdefs.h +elif test "$libc_cv_ehdr_start" = broken; then + { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: linker is broken -- you should upgrade" >&5 +$as_echo "$as_me: WARNING: linker is broken -- you should upgrade" >&2;} fi { $as_echo "$as_me:${as_lineno-$LINENO}: checking for __builtin_trap with no external dependencies" >&5 diff --git a/configure.ac b/configure.ac index e89faa0dfe..255339983a 100644 --- a/configure.ac +++ b/configure.ac @@ -1880,7 +1880,10 @@ if test $libc_cv_predef_stack_protector = yes; then fi libc_extra_cppflags= -AC_CACHE_CHECK([whether the linker provides __ehdr_start], +# Some linkers on some architectures support __ehdr_start but with +# bugs. Make sure usage of it does not create relocations in the +# output (as the linker should resolve them all for us). +AC_CACHE_CHECK([whether the linker provides working __ehdr_start], libc_cv_ehdr_start, [ old_CFLAGS="$CFLAGS" old_LDFLAGS="$LDFLAGS" @@ -1889,16 +1892,26 @@ CFLAGS="$CFLAGS -fPIC" LDFLAGS="$LDFLAGS -nostdlib -nostartfiles -shared" LIBS= AC_LINK_IFELSE([AC_LANG_SOURCE([ -extern const char __ehdr_start __attribute__ ((visibility ("hidden"))); -const char *ehdr (void) { return &__ehdr_start; } +typedef struct { + char foo; + long val; +} Ehdr; +extern const Ehdr __ehdr_start __attribute__ ((visibility ("hidden"))); +long ehdr (void) { return __ehdr_start.val; } ])], - [libc_cv_ehdr_start=yes], [libc_cv_ehdr_start=no]) + [if $READELF -r conftest | fgrep __ehdr_start >/dev/null; then + libc_cv_ehdr_start=broken + else + libc_cv_ehdr_start=yes + fi], [libc_cv_ehdr_start=no]) CFLAGS="$old_CFLAGS" LDFLAGS="$old_LDFLAGS" LIBS="$old_LIBS" ]) -if test $libc_cv_ehdr_start = yes; then +if test "$libc_cv_ehdr_start" = yes; then AC_DEFINE([HAVE_EHDR_START]) +elif test "$libc_cv_ehdr_start" = broken; then + AC_MSG_WARN([linker is broken -- you should upgrade]) fi AC_CACHE_CHECK(for __builtin_trap with no external dependencies, |