diff options
Diffstat (limited to 'configure.ac')
| -rw-r--r-- | configure.ac | 75 |
1 files changed, 24 insertions, 51 deletions
diff --git a/configure.ac b/configure.ac index f5fa1aaefa..2782bfaf08 100644 --- a/configure.ac +++ b/configure.ac @@ -665,11 +665,26 @@ elif test "$enable_stack_protector" = all && test "$libc_cv_ssp_all" = yes; then elif test "$enable_stack_protector" = strong && test "$libc_cv_ssp_strong" = yes; then stack_protector="-fstack-protector-strong" AC_DEFINE(STACK_PROTECTOR_LEVEL, 3) +else + stack_protector="-fno-stack-protector" + AC_DEFINE(STACK_PROTECTOR_LEVEL, 0) fi AC_SUBST(libc_cv_ssp) AC_SUBST(stack_protector) AC_SUBST(no_stack_protector) +if test -n "$stack_protector"; then + dnl Don't run configure tests with stack-protection on, to avoid problems with + dnl bootstrapping. + no_ssp=-fno-stack-protector +else + no_ssp= + + if test "$enable_stack_protector" != no; then + AC_MSG_ERROR([--enable-stack-protector=$enable_stack_protector specified, but specified level of stack protection is not supported by the compiler.]) + fi +fi + # For the multi-arch option we need support in the assembler & linker. AC_CACHE_CHECK([for assembler and linker STT_GNU_IFUNC support], libc_cv_ld_gnu_indirect_function, [dnl @@ -689,7 +704,7 @@ __start: EOF libc_cv_ld_gnu_indirect_function=no if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \ - -nostartfiles -nostdlib \ + -nostartfiles -nostdlib $no_ssp \ -o conftest conftest.S 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then # Do a link to see if the backend supports IFUNC relocs. $READELF -r conftest 1>&AS_MESSAGE_LOG_FD @@ -1213,7 +1228,7 @@ extern int glibc_conftest_frobozz; void _start() { glibc_conftest_frobozz = 1; } EOF if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS \ - -nostartfiles -nostdlib \ + -nostartfiles -nostdlib $no_ssp \ -o conftest conftest.s conftest1.c 1>&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD; then libc_cv_asm_set_directive=yes else @@ -1230,12 +1245,12 @@ AC_CACHE_CHECK(linker support for protected data symbol, int bar __attribute__ ((visibility ("protected"))) = 1; EOF libc_cv_protected_data=no - if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles -fPIC -shared conftest.c -o conftest.so); then + if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp -fPIC -shared conftest.c -o conftest.so); then cat > conftest.c <<EOF extern int bar; int main (void) { return bar; } EOF - if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles conftest.c -o conftest conftest.so); then + if AC_TRY_COMMAND(${CC-cc} -nostdlib -nostartfiles $no_ssp conftest.c -o conftest conftest.so); then libc_cv_protected_data=yes fi fi @@ -1357,7 +1372,7 @@ extern int mumble; int foo (void) { return bar (mumble); } EOF if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS - -fPIC -shared -o conftest.so conftest.c + -fPIC -shared $no_ssp -o conftest.so conftest.c -nostdlib -nostartfiles -Wl,-z,combreloc 1>&AS_MESSAGE_LOG_FD]) then @@ -1395,7 +1410,7 @@ AC_CACHE_CHECK(for --hash-style option, cat > conftest.c <<EOF int _start (void) { return 42; } EOF -if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS +if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp -fPIC -shared -o conftest.so conftest.c -Wl,--hash-style=both -nostdlib 1>&AS_MESSAGE_LOG_FD]) then @@ -1467,7 +1482,7 @@ int foo (void) { return mumble; } EOF if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -fPIC -shared -o conftest.so conftest.c - -nostdlib -nostartfiles + -nostdlib -nostartfiles $no_ssp 1>&AS_MESSAGE_LOG_FD]) then dnl look for GLOB_DAT relocation. @@ -1484,7 +1499,7 @@ AC_SUBST(libc_cv_has_glob_dat) AC_CACHE_CHECK(linker output format, libc_cv_output_format, [dnl if libc_cv_output_format=` -${CC-cc} -nostartfiles -nostdlib -Wl,--print-output-format 2>&AS_MESSAGE_LOG_FD` +${CC-cc} -nostartfiles -nostdlib $no_ssp -Wl,--print-output-format 2>&AS_MESSAGE_LOG_FD` then : else @@ -1703,48 +1718,6 @@ if test $libc_cv_predef_fortify_source = yes; then fi AC_SUBST(CPPUNDEFS) -dnl Check for silly hacked compilers inserting -fstack-protector. -dnl This breaks badly for the early startup code we compile, since -dnl the compiled code can refer to a magic machine-dependent location -dnl for the canary value before we have sufficient setup for that to -dnl work. It's also questionable to build all of libc with this flag -dnl even when you're doing that for most applications you build, since -dnl libc's code is so heavily-used and performance-sensitive. If we -dnl ever really want to make that work, it should be enabled explicitly -dnl in the libc build, not inherited from implicit compiler settings. -AC_CACHE_CHECK([whether $CC implicitly enables -fstack-protector], - libc_cv_predef_stack_protector, [ -AC_TRY_COMPILE([extern void foobar (char *);], - [char large_array[2048]; foobar (large_array);], [ -libc_undefs=`$NM -u conftest.o | - LC_ALL=C $AWK '$1 == "U" { print $2 | "sort -u"; next } { exit(1) }' \ - 2>&AS_MESSAGE_LOG_FD` || { - AC_MSG_ERROR([confusing output from $NM -u]) -} -echo >&AS_MESSAGE_LOG_FD "libc_undefs='$libc_undefs'" -# On some architectures, there are architecture-specific undefined -# symbols (resolved by the linker), so filter out unknown symbols. -# This will fail to produce the correct result if the compiler -# defaults to -fstack-protector but this produces an undefined symbol -# other than __stack_chk_fail or __stack_chk_fail_local. However, -# compilers like that have not been encountered in practice. -libc_undefs=`echo "$libc_undefs" | \ - egrep '^(foobar|__stack_chk_fail|__stack_chk_fail_local)$'` -case "$libc_undefs" in -foobar) libc_cv_predef_stack_protector=no ;; -'__stack_chk_fail -foobar'|'__stack_chk_fail_local -foobar') libc_cv_predef_stack_protector=yes ;; -*) AC_MSG_ERROR([unexpected symbols in test: $libc_undefs]) ;; -esac], - [AC_MSG_ERROR([test compilation failed])]) -]) -libc_extra_cflags= -if test $libc_cv_predef_stack_protector = yes; then - libc_extra_cflags="$libc_extra_cflags -fno-stack-protector" -fi -libc_extra_cppflags= - # 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). @@ -1754,7 +1727,7 @@ old_CFLAGS="$CFLAGS" old_LDFLAGS="$LDFLAGS" old_LIBS="$LIBS" CFLAGS="$CFLAGS -fPIC" -LDFLAGS="$LDFLAGS -nostdlib -nostartfiles -shared" +LDFLAGS="$LDFLAGS -nostdlib -nostartfiles -shared $no_ssp" LIBS= AC_LINK_IFELSE([AC_LANG_SOURCE([ typedef struct { |