Re: [PATCH v3 1/2] Makefile scripts/Makefile.lib: fix *_efi.so dependency to PLATFORM_LIBGCC

[Mikko Rapeli <mikko.rapeli@linaro.org>]

Hi,

On Mon, Jul 28, 2025 at 03:43:49PM -0600, Tom Rini wrote:
> On Fri, Jul 18, 2025 at 11:29:58AM +0300, Mikko Rapeli wrote:
> 
> > When PLATFORM_LIBGCC was added to linker command it was not
> > added to the dependency of the .so and other rules. Thus a build can
> > try to link *_efi.so files before lib.a from PLATFORM_LIBGCC is available.
> > This was seen in yocto autobuilder builds with u-boot 2025.07
> > update, see https://lists.openembedded.org/g/openembedded-core/message/220004
> > 
> > https://autobuilder.yoctoproject.org/valkyrie/api/v2/logs/2914600/raw_inline
> > 
> > |    rm -f lib/efi_loader/built-in.o; arm-poky-linux-gnueabi-ar cDPrsT lib/efi_loader/built-in.o lib/efi_loader/efi_bootmgr.o lib/efi_loader/efi_bootbin.o lib/efi_loader/efi_boottime.o lib/efi_loader/efi_helper.o lib/efi_loader/efi_console.o lib/efi_loader/efi_device_path.o lib/efi_loader/efi_device_path_to_text.o lib/efi_loader/efi_device_path_utilities.o lib/efi_loader/efi_dt_fixup.o lib/efi_loader/efi_fdt.o lib/efi_loader/efi_file.o lib/efi_loader/efi_hii.o lib/efi_loader/efi_hii_config.o lib/efi_loader/efi_image_loader.o lib/efi_loader/efi_load_options.o lib/efi_loader/efi_memory.o lib/efi_loader/efi_root_node.o lib/efi_loader/efi_runtime.o lib/efi_loader/efi_setup.o lib/efi_loader/efi_string.o lib/efi_loader/efi_unicode_collation.o lib/efi_loader/efi_var_common.o lib/efi_loader/efi_var_mem.o lib/efi_loader/efi_variable.o lib/efi_loader/efi_var_file.o lib/efi_loader/efi_watchdog.o lib/efi_loader/efi_disk.o lib/efi_loader/efi_net.o lib/efi_loader/efi_smbios.o lib/efi_loader/efi_load_initrd.o lib/efi_loader/efi_conformance.o
> > |   arm-poky-linux-gnueabi-ld.bfd -nostdlib -zexecstack -znocombreloc -znorelro --no-warn-rwx-segments -L /srv/pokybuild/yocto-worker/oe-selftest-armhost/build/build-st-3119200/tmp/work/beaglebone_yocto-poky-linux-gnueabi/u-boot/2025.07/sources/u-boot-2025.07 -T arch/arm/lib/elf_arm_efi.lds -shared -Bsymbolic -s lib/efi_loader/helloworld.o lib/efi_loader/efi_crt0.o lib/efi_loader/efi_reloc.o lib/efi_loader/efi_freestanding.o arch/arm/lib/lib.a -o lib/efi_loader/helloworld_efi.so
> > | arm-poky-linux-gnueabi-ld.bfd: cannot find arch/arm/lib/lib.a: No such file or directory
> > | make[3]: *** [scripts/Makefile.lib:512: lib/efi_loader/helloworld_efi.so] Error 1
> > 
> > The issue is hard to reproduce but this change can artificially trigger it:
> > 
> >   --- a/scripts/Makefile.build
> >   +++ b/scripts/Makefile.build
> > @@ -353,7 +353,7 @@ $(modorder-target): $(subdir-ym) FORCE
> >  #
> >  ifdef lib-target
> >  quiet_cmd_link_l_target = AR      $@
> > -cmd_link_l_target = rm -f $@; $(AR) cDPrsT$(KBUILD_ARFLAGS) $@ $(lib-y)
> > +cmd_link_l_target = rm -f $@ && echo "HACK, delaying build!" && sleep 60 && $(AR) cDPrsT$(KBUILD_ARFLAGS) $@ $(lib-y)
> > 
> >  $(lib-target): $(lib-y) FORCE
> >         $(call if_changed,link_l_target)
> > 
> > Then run a rebuild with:
> > 
> > $  rm -f $( find build/ -name lib.a -or -name helloworld_efi.so ) && \
> >    make
> > ...
> >   arm-poky-linux-gnueabi-ld.bfd -nostdlib -zexecstack -znocombreloc -znorelro --no-warn-rwx-segments -L /home/mcfrisk/src/base/repo/poky/build_bea
> > glebone/tmp/work/beaglebone_yocto-poky-linux-gnueabi/u-boot/2025.07/sources/u-boot-2025.07 -T arch/arm/lib/elf_arm_efi.lds -shared -Bsymbolic -s lib/efi_loader/helloworld.o lib/efi_loader/efi_crt0.o lib/efi_loader/efi_reloc.o lib/efi_loader/efi_freestanding.o arch/arm/lib/lib.a -o lib/efi_loader/helloworld_efi.so
> > arm-poky-linux-gnueabi-ld.bfd: cannot find arch/arm/lib/lib.a: No such file or directory
> > make[3]: *** [scripts/Makefile.lib:512: lib/efi_loader/helloworld_efi.so] Error 1
> > 
> > Fix by introducing PLATFORM_LIBGCC_LIBA variable with only lib.a
> > filename which is then used to add the dependency in rules which use
> > PLATFORM_LIBGCC. This should not impact builds which don't set
> > PLATFORM_LIBGCC_LIBA and PLATFORM_LIBGCC usage stays as is.
> > 
> > Fixes: 43d43241d1c9 ("scripts/Makefile.lib: add PLATFORM_LIBGCC to efi linking")
> > 
> > Cc: Adriano Cordova <adrianox@gmail.com>
> > Cc: Fabio Estevam <festevam@gmail.com>
> > Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
> 
> So, this series needs a cover letter. And to reword the commit messages,
> so that the diff to make things fail shows up below the "---". But the
> fatal problem for right now is this needs to be put through CI next
> time. This seems to cause some of the EFI apps to not be built now:
> https://source.denx.de/u-boot/u-boot/-/jobs/1209924
> 
> I assume Azure would have failed too if I let it get that far. Thanks.

I think I finally figured this out and will send a patch to Makefile in v4.
arch/$(ARCH)/lib and lib are compiled by separate "make" processes started
by top level Makefile, and both use the same scripts/Makefile.build etc. This
threw me off quite a bit. And "make" does not tell which dependencies of a
target are missing if the file level dependency to lib.a is explicit when linking
the EFI apps.

I think the single change to build "arch/$(ARCH)/lib" directory before "lib"
in top level Makefile is simple enough to explain in commit message
without a coverletter, similar to how "examples" directory is compiled after
all other directories for u-boot binaries.

Cheers,

-Mikko