On Tue, Jul 28, 2020 at 6:33 AM H.J. Lu <hjl.to...@gmail.com> wrote: > > On Tue, Jul 28, 2020 at 5:46 AM Simon Marchi <sim...@simark.ca> wrote: > > > > On 2020-07-28 6:45 a.m., H.J. Lu wrote: > > > On Mon, Jul 27, 2020 at 12:32 PM H.J. Lu <hjl.to...@gmail.com> wrote: > > >> > > >> On Mon, Jul 27, 2020 at 12:14 PM H.J. Lu <hjl.to...@gmail.com> wrote: > > >>> > > >>> On Mon, Jul 27, 2020 at 9:11 AM Aaron Merey <ame...@redhat.com> wrote: > > >>>> > > >>>> On Mon, Jul 27, 2020 at 11:32 AM H.J. Lu <hjl.to...@gmail.com> wrote: > > >>>>> > > >>>>> On Sat, Jul 25, 2020 at 9:01 AM H.J. Lu <hjl.to...@gmail.com> wrote: > > >>>>>> This caused: > > >>>>>> > > >>>>>> https://sourceware.org/bugzilla/show_bug.cgi?id=26301 > > >>>>>> > > >>>>> > > >>>>> It is quite normal to have debuginfod headers without libdebuginfod on > > >>>>> multilib OSes. Restore AC_CHECK_LIB to check if libdebuginfod exists. > > >>>>> And always define HAVE_LIBDEBUGINFOD to 0 or 1 for > > >>>>> > > >>>>> binutils/dwarf.c:#if HAVE_LIBDEBUGINFOD > > >>>>> binutils/dwarf.c:#if HAVE_LIBDEBUGINFOD > > >>>>> binutils/dwarf.c:#if HAVE_LIBDEBUGINFOD > > >>>>> binutils/dwarf.h:#if HAVE_LIBDEBUGINFOD > > >>>>> binutils/objdump.c:#if HAVE_LIBDEBUGINFOD > > >>>>> binutils/objdump.c:#endif /* HAVE_LIBDEBUGINFOD */ > > >>>>> binutils/readelf.c:#if HAVE_LIBDEBUGINFOD > > >>>>> binutils/readelf.c:#endif /* HAVE_LIBDEBUGINFOD */ > > >>>>> gdb/top.c:#if HAVE_LIBDEBUGINFOD > > >>>>> > > >>>>> OK for master? > > >>>> > > >>>> Thanks for spotting this. Normally PKG_CHECH_MODULES would correctly > > >>>> detect whether the .so and header are installed and build accordingly, > > >>>> but when cross compiling the AC_CHECK_LIB may be needed. > > >>> > > >>> I am not cross compiling. I am simply using "gcc -m32". The problem > > >>> is PKG_CHECK_MODULES which doesn't check if $pkg_cv_[]$1[]_LIBS > > >>> actually works. Here is the updated patch to fix PKG_CHECK_MODULES. > > >>> Any comments or objections? > > >>> > > >>> > > >> > > >> HAVE_LIBDEBUGINFOD is a separate issue. Here is the updated patch > > >> which only adds AC_TRY_LINK to PKG_CHECK_MODULES to check if > > >> $pkg_cv_[]$1[]_LIBS works. > > >> > > > > > > I am checking it in. > > > > > > -- > > > H.J. > > > > > > > You said that you are not cross-compiling, but technically I'd say you are > > cross compiling, since > > you are building for a different architecture than what the compiler is > > running. You are probably > > configuring with --host=i686-something-something? > > On x86, the native GCC can support -m32 and -m64. "gcc -m32" or "gcc -m64" > are not cross compiling. > > > Anyway regardless of vocabulary, I don't think there was a problem to begin > > with (not that I blame > > you, it's not made in an intuitive way). The problem is that you were > > using pkg-config as > > configured to look up x86_64 packages. It looks up .pc files in (amongst > > others) > > /usr/lib64/pkgconfig, which provides information about x86_64 packages, > > which are in turn obviously > > not suitable not suitable to build a i686 program. Just like you > > cross-compile "for real" (say, > > for an ARM host), you need to set PKG_CONFIG or the PKG_CONFIG_* variables > > to returns packages for > > the --host architecture. That means searching in /usr/lib/pkgconfig > > instead of /usr/lib64/pkgconfig. > > > > You could for example set the PKG_CONFIG_LIBDIR variable to > > /usr/lib/pkgconfig:/usr/share/pkgconfig > > I didn't set PKG_CONFIG_LIBDIR and I don't want to set it. > > > This way, if you don't install the elfutils-debuginfod-client-devel.i686 > > package, your binutils won't > > try to link with libdebuginfod (because pkg-config won't find it). If you > > install it, then your > > binutils will be built against the i686 libdebuginfod. > > > > Ideally, distros would ship a i686-something-something-pkg-config that > > automatically searchs in paths > > that make sense for that architecture (just like you have > > arm-linux-gnueabihf-pkg-config when cross > > compiling for ARM), but that doesn't seem to exist. But this is just like > > you have to explicitly set > > CC="gcc -m32" instead of using some i686-something-something-gcc. > > > > You can always make it yourself, create, say, a > > `i686-pc-linux-gnu-pkg-config` file somewhere in $PATH, > > with: > > > > export PKG_CONFIG_LIBDIR=/usr/lib/pkgconfig:/usr/share/pkgconfig > > exec pkg-config $* > > I don't want to do it. PKG_CHECK_MODULES should check if the library > really works. > Otherwise we can use remove it and use the library directly without checking. > > > Then, when you configure with --host=i686-pc-linux-gnu, AC_PATH_TOOL will > > automatically pick up that as > > the pkg-config to use, and everything will work seamlessly. > > > > So, I concede that it's not intuitive, but I think your patch is not right > > because it just hides the > > mis-configuration. If `pkg-config` says a lib exists but we are not able > > to link with it, there is a > > bigger problem than "lib not found". I think it should be a hard error > > (abort configure) and tell the > > user about it: "pkg-config says that libfoo is available but we can't link > > with it, are you maybe using > > the wrong pkg-config, or a wrong pkg-config path?". > > > > Finally, the file you modified is maintained upstream here: > > > > https://cgit.freedesktop.org/pkg-config/tree/pkg.m4.in > > > > Do you intend to submit your changes there? Otherwise, they will be > > overwritten next time we sync with > > upstream. > > > > Will do. > > -- > H.J.
https://gitlab.freedesktop.org/pkg-config/pkg-config/-/merge_requests/6 -- H.J.
