On Fri, 4 Oct 2024 at 10:50, Kyrylo Tkachov <ktkac...@nvidia.com> wrote:
>
>
>
> > On 3 Oct 2024, at 21:44, Christophe Lyon <christophe.l...@linaro.org> wrote:
> >
> > External email: Use caution opening links or attachments
> >
> >
> > 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 aarch64 part is ok but you’ll need a wider libgcc approval.
> It seems to me that if libgcc is intended to compile cleanly with -Werror
> then it should be a libgcc-wide change, but maybe doing it port-by-port is
> the only practical way of getting there?
Indeed, it was not clear to me if libgcc is supposed to compile
without warnings.... My feeling is that warnings or often worth having
a look, but without -Werror they get unnoticed.
Adding Ian in cc as libgcc maintainer.
Thanks,
Christophe
> Thanks,
> Kyrill
>
>
> > 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/Makefile.in b/libgcc/Makefile.in
> > index 0e46e9ef768..eca62546642 100644
> > --- a/libgcc/Makefile.in
> > +++ b/libgcc/Makefile.in
> > @@ -84,6 +84,7 @@ AR_FLAGS = rc
> >
> > CC = @CC@
> > CFLAGS = @CFLAGS@
> > +WERROR = @WERROR@
> > RANLIB = @RANLIB@
> > LN_S = @LN_S@
> >
> > 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 += $(WERROR) -Wno-prio-ctor-dtor
> > diff --git a/libgcc/configure b/libgcc/configure
> > index cff1eff9625..ae56f7dbdc9 100755
> > --- a/libgcc/configure
> > +++ b/libgcc/configure
> > @@ -592,6 +592,7 @@ enable_execute_stack
> > asm_hidden_op
> > extra_parts
> > cpu_type
> > +WERROR
> > get_gcc_base_ver
> > HAVE_STRUB_SUPPORT
> > thread_header
> > @@ -719,6 +720,7 @@ enable_tm_clone_registry
> > with_glibc_version
> > enable_tls
> > with_gcc_major_version_only
> > +enable_werror_always
> > '
> > ac_precious_vars='build_alias
> > host_alias
> > @@ -1361,6 +1363,7 @@ Optional Features:
> > installations without PT_GNU_EH_FRAME support
> > --disable-tm-clone-registry disable TM clone registry
> > --enable-tls Use thread-local storage [default=yes]
> > + --enable-werror-always enable -Werror despite compiler version
> >
> > Optional Packages:
> > --with-PACKAGE[=ARG] use PACKAGE [ARG=yes]
> > @@ -5808,6 +5811,34 @@ fi
> >
> >
> >
> > +# Only enable with --enable-werror-always until existing warnings are
> > +# corrected.
> > +ac_ext=c
> > +ac_cpp='$CPP $CPPFLAGS'
> > +ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
> > +ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS
> > conftest.$ac_ext $LIBS >&5'
> > +ac_compiler_gnu=$ac_cv_c_compiler_gnu
> > +
> > +WERROR=
> > +# Check whether --enable-werror-always was given.
> > +if test "${enable_werror_always+set}" = set; then :
> > + enableval=$enable_werror_always;
> > +else
> > + enable_werror_always=no
> > +fi
> > +
> > +if test $enable_werror_always = yes; then :
> > + WERROR="$WERROR${WERROR:+ }-Werror"
> > +fi
> > +
> > +ac_ext=c
> > +ac_cpp='$CPP $CPPFLAGS'
> > +ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
> > +ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS
> > conftest.$ac_ext $LIBS >&5'
> > +ac_compiler_gnu=$ac_cv_c_compiler_gnu
> > +
> > +
> > +
> > # Substitute configuration variables
> >
> >
> > 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])
> > +
> > # Substitute configuration variables
> > AC_SUBST(cpu_type)
> > AC_SUBST(extra_parts)
> > --
> > 2.34.1
> >
>
