| Message ID | 578F8388.8060605@arm.com |
|---|---|
| State | New |
| Headers | show |
On 20/07/16 14:58, Szabolcs Nagy wrote: > since gcc can be built with --enable-default-pie, there > is a -no-pie flag to turn off PIE. > > gcc cannot be built as PIE (pr 71934), so the gcc build > system has to detect the -no-pie flag to disable PIE. > > historically default pie toolchains used the -nopie flag > (e.g. gentoo hardened), those toolchains cannot build > gcc anymore, so detect -nopie too. > > gcc/ > 2016-07-20 Szabolcs Nagy <szabolcs.nagy@arm.com> > > * configure.ac: Detect -nopie flag just like -no-pie. > * configure: Regenerate. > ping
onsdag 24 augusti 2016 kl. 18:21:07 CEST skrev Szabolcs Nagy: > On 20/07/16 14:58, Szabolcs Nagy wrote: > > since gcc can be built with --enable-default-pie, there > > is a -no-pie flag to turn off PIE. > > > > gcc cannot be built as PIE (pr 71934), so the gcc build > > system has to detect the -no-pie flag to disable PIE. > > > > historically default pie toolchains used the -nopie flag > > (e.g. gentoo hardened), those toolchains cannot build > > gcc anymore, so detect -nopie too. > > > > gcc/ > > 2016-07-20 Szabolcs Nagy <szabolcs.nagy@arm.com> > > > > * configure.ac: Detect -nopie flag just like -no-pie. > > * configure: Regenerate. > > ping On Gentoo Hardened we are moving to use -no-pie to disable the linking part for both gcc and ld/gold support it. -nopie was not supported by upstream. To disable PIE when compile -fno-PIE should be just. The compile and link part is disable when building gcc, look in the Makefile. /Magnus G.
diff --git a/gcc/configure b/gcc/configure index ed44472..ca16e66 100755 --- a/gcc/configure +++ b/gcc/configure @@ -29566,6 +29566,33 @@ fi $as_echo "$gcc_cv_no_pie" >&6; } if test "$gcc_cv_no_pie" = "yes"; then NO_PIE_FLAG="-no-pie" +else + # Check if -nopie works. + { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -nopie option" >&5 +$as_echo_n "checking for -nopie option... " >&6; } +if test "${gcc_cv_nopie+set}" = set; then : + $as_echo_n "(cached) " >&6 +else + saved_LDFLAGS="$LDFLAGS" + LDFLAGS="$LDFLAGS -nopie" + cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ +int main(void) {return 0;} +_ACEOF +if ac_fn_cxx_try_link "$LINENO"; then : + gcc_cv_nopie=yes +else + gcc_cv_nopie=no +fi +rm -f core conftest.err conftest.$ac_objext \ + conftest$ac_exeext conftest.$ac_ext + LDFLAGS="$saved_LDFLAGS" +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_nopie" >&5 +$as_echo "$gcc_cv_nopie" >&6; } + if test "$gcc_cv_nopie" = "yes"; then + NO_PIE_FLAG="-nopie" + fi fi diff --git a/gcc/configure.ac b/gcc/configure.ac index 086d0fc..98ab5cb 100644 --- a/gcc/configure.ac +++ b/gcc/configure.ac @@ -6200,6 +6200,19 @@ AC_CACHE_CHECK([for -no-pie option], LDFLAGS="$saved_LDFLAGS"]) if test "$gcc_cv_no_pie" = "yes"; then NO_PIE_FLAG="-no-pie" +else + # Check if -nopie works. + AC_CACHE_CHECK([for -nopie option], + [gcc_cv_nopie], + [saved_LDFLAGS="$LDFLAGS" + LDFLAGS="$LDFLAGS -nopie" + AC_LINK_IFELSE([int main(void) {return 0;}], + [gcc_cv_nopie=yes], + [gcc_cv_nopie=no]) + LDFLAGS="$saved_LDFLAGS"]) + if test "$gcc_cv_nopie" = "yes"; then + NO_PIE_FLAG="-nopie" + fi fi AC_SUBST([NO_PIE_FLAG])