Richard Sandiford <richard.sandif...@arm.com> writes: > Christophe Lyon <christophe.l...@linaro.org> writes: >> When --enable-werror is enabled when running the top-level configure, >> it passes --enable-werror-always to subdirs. Some of them, like >> libgcc, ignore it. >> >> This patch adds support for it, enabled only for aarch64, to avoid >> breaking bootstrap for other targets. >> >> The patch also adds -Wno-prio-ctor-dtor to avoid a warning when compiling >> lse_init.c >> >> libgcc/ >> * Makefile.in (WERROR): New. >> * config/aarch64/t-aarch64: Handle WERROR. Always use >> -Wno-prio-ctor-dtor. >> * configure.ac: Add support for --enable-werror-always. >> * configure: Regenerate. >> --- >> libgcc/Makefile.in | 1 + >> libgcc/config/aarch64/t-aarch64 | 1 + >> libgcc/configure | 31 +++++++++++++++++++++++++++++++ >> libgcc/configure.ac | 5 +++++ >> 4 files changed, 38 insertions(+) >> >> [...] >> diff --git a/libgcc/configure.ac b/libgcc/configure.ac >> index 4e8c036990f..6b3ea2aea5c 100644 >> --- a/libgcc/configure.ac >> +++ b/libgcc/configure.ac >> @@ -13,6 +13,7 @@ sinclude(../config/unwind_ipinfo.m4) >> sinclude(../config/gthr.m4) >> sinclude(../config/sjlj.m4) >> sinclude(../config/cet.m4) >> +sinclude(../config/warnings.m4) >> >> AC_INIT([GNU C Runtime Library], 1.0,,[libgcc]) >> AC_CONFIG_SRCDIR([static-object.mk]) >> @@ -746,6 +747,10 @@ AC_SUBST(HAVE_STRUB_SUPPORT) >> # Determine what GCC version number to use in filesystem paths. >> GCC_BASE_VER >> >> +# Only enable with --enable-werror-always until existing warnings are >> +# corrected. >> +ACX_PROG_CC_WARNINGS_ARE_ERRORS([manual]) > > It looks like this is borrowed from libcpp and/or libdecnumber. > Those are a bit different from libgcc in that they're host libraries > that can be built with any supported compiler (including non-GCC ones). > In constrast, libgcc can only be built with the corresponding version > of GCC. The usual restrictions on -Werror -- only use it during stages > 2 and 3, or if the user explicitly passes --enable-werror -- don't apply > in libgcc's case. We should always be building with the "right" version > of GCC (even for Canadian crosses) and so should always be able to use > -Werror. > > So personally, I think we should just go with: > > diff --git a/libgcc/config/aarch64/t-aarch64 b/libgcc/config/aarch64/t-aarch64 > index b70e7b94edd..ae1588ce307 100644 > --- a/libgcc/config/aarch64/t-aarch64 > +++ b/libgcc/config/aarch64/t-aarch64 > @@ -30,3 +30,4 @@ LIB2ADDEH += \ > $(srcdir)/config/aarch64/__arm_za_disable.S > > SHLIB_MAPFILES += $(srcdir)/config/aarch64/libgcc-sme.ver > +LIBGCC2_CFLAGS += $(WERROR) -Wno-prio-ctor-dtor > > ...this, but with $(WERROR) replaced by -Werror. > > At least, it would be a good way of finding out if there's a case > I've forgotten :) > > Let's see what others think though.
As per the later discussion, the t-aarch64 change described above is OK for trunk, but anyone with commit access should feel free to revert it if it breaks their build. (Although please post a description of what went wrong as well :)) Thanks for doing this. Richard
