[PATCH v3 1/4] Makeconfig: Add libgcc directory to rtld-prefix search path

[Adhemerval Zanella Netto]

On 23/06/25 11:12, dilfridge@gentoo.org wrote:
> From: Andreas K. Hüttel <dilfridge@gentoo.org>
> 
> * This needs to be done twice, for test runs with and without
>   --enable-hardcoded-path-in-tests
> * Also, we need to query the used $(CC) for the library location.
> 
> * The container tests run ldd and dump the list of needed libraries, then
>   copy these into the container.
> * Without this patch, ldd may not find libgcc_s.so, resulting in"not found"
>   output and no copying of the library.
> * With this patch, the library is picked up independent of its location (as
>   long as the proper directory is provided) and copied into the testroot.
> 
> * This does not mean yet that ld.so in the testroot actually finds it.
> 
> Signed-off-by: Andreas K. Hüttel <dilfridge@gentoo.org>
> ---
> v3: use command line suggested by Adhemerval for gnulib-extralibdir

LGTM, on debian-like system it now adds the rpath/--library-path correctly
on tests. And it also fixes the stdio-common/tst-setvbuf2 issues so I 
think it should mark as fixing BZ#32869.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

> ---
>  Makeconfig | 12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/Makeconfig b/Makeconfig
> index 1bb143e950..1f8c912011 100644
> --- a/Makeconfig
> +++ b/Makeconfig
> @@ -639,7 +639,7 @@ link-libc-printers-tests = $(link-libc-rpath) \
>  # This is how to find at build-time things that will be installed there.
>  rpath-dirs = math elf dlfcn nss nis rt resolv mathvec support misc debug
>  rpath-link = \
> -$(common-objdir):$(subst $(empty) ,:,$(patsubst ../$(subdir),.,$(rpath-dirs:%=$(common-objpfx)%)))
> +$(common-objdir):$(subst $(empty) ,:,$(patsubst ../$(subdir),.,$(rpath-dirs:%=$(common-objpfx)%))):$(gnulib-extralibdir)
>  else  # build-static
>  link-libc = $(common-objpfx)libc.a $(otherlibs) $(gnulib) $(common-objpfx)libc.a $(gnulib)
>  link-libc-tests = $(common-objpfx)libc.a $(otherlibs) $(gnulib-tests) $(common-objpfx)libc.a $(gnulib-tests)
> @@ -696,6 +696,11 @@ link-libc-static-tests = -Wl,--start-group $(common-objpfx)libc.a $(static-gnuli
>  # some cases and it is preferable to link with libgcc_eh or libgcc_s
>  # so that the testing is as similar as possible to how programs will
>  # be built with the installed glibc.
> +# This leads to moderate difficulties, also since distributions may
> +# install libgcc_s.so in directories only found via ld.so.conf, e.g.
> +# to be able to switch between gcc versions. We need to add the
> +# corresponding directory to the library search path to make sure
> +# our test programs can find it.
>  #
>  # Some architectures have architecture-specific systems for exception
>  # handling that may involve undefined references to
> @@ -713,6 +718,7 @@ libgcc_eh := -Wl,--as-needed -lgcc_s $(libunwind) -Wl,--no-as-needed
>  gnulib-arch =
>  gnulib = -lgcc $(gnulib-arch)
>  gnulib-tests := -lgcc $(libgcc_eh)
> +gnulib-extralibdir = $(shell $(CC) -print-file-name=libgcc_s.so$(libgcc_s.so-version) | sed 's#/[^/]*$$##')
>  static-gnulib-arch =
>  # By default, elf/static-stubs.o, instead of -lgcc_eh, is used to
>  # statically link programs.  When --disable-shared is used, we use
> @@ -785,10 +791,12 @@ endif
>  
>  # How to run a program we just linked with our library.
>  # The program binary is assumed to be $(word 2,$^).
> +# We may require additional libraries from gcc (e.g. libgcc_s.so for exception
> +# handling), which unfortunately somewhat breaks the isolation.
>  built-program-file = $(dir $(word 2,$^))$(notdir $(word 2,$^))
>  rtld-prefix = $(elf-objpfx)$(rtld-installed-name)			      \
>  	      --library-path						      \
> -	      $(rpath-link)$(patsubst %,:%,$(sysdep-library-path))
> +	      $(rpath-link)$(patsubst %,:%,$(sysdep-library-path)):$(gnulib-extralibdir)
>  ifeq (yes,$(build-shared))
>  comma = ,
>  sysdep-library-path = \