Building justbuild fails with GCC 13.2 due to partial specialization of ‘struct fmt::v10::formatter<std::__cxx11::basic_string<...>>

[mhthies]

I tried to change my Arch Linux package recipe to use GCC instead of Clang and ran into another {fmt}-related issue:

In file included from /usr/include/fmt/ostream.h:20,
                 from /home/michael/Documents/Freizeit/Programme/pkgbuild/justbuild/src/build/src/src/utils/cpp/json.hpp:25,
                 from /home/michael/Documents/Freizeit/Programme/pkgbuild/justbuild/src/build/src/src/buildtool/common/artifact_description.hpp:27,
                 from /home/michael/Documents/Freizeit/Programme/pkgbuild/justbuild/src/build/src/src/buildtool/build_engine/expression/target_result.hpp:23,
                 from /home/michael/Documents/Freizeit/Programme/pkgbuild/justbuild/src/build/src/src/buildtool/build_engine/expression/target_result.cpp:15:
/usr/include/fmt/format.h:4076:1: error: partial specialization of ‘struct fmt::v10::formatter<std::__cxx11::basic_string<_CharT>, Char>’ after instantiation of ‘struct fmt::v10::formatter<std::__cxx11::basic_string<char>, char, void>’ [-fpermissive]
 4076 | FMT_FORMAT_AS(std::basic_string<Char>, basic_string_view<Char>);
      | ^~~~~~~~~~~~~

(and many similar occurances; all of them caused by artifact_description.hpp being included somehow.)

This might be introduced by my patch (#42) and sounds similar to this issue: fmtlib/fmt#2769

I was able to fully fix the problem by replacing the #include "fmt/core.h" with #include "fmt/format.h" in logger.hpp.

Tested with fmt 10.1.0.

[spc90]

Hi @mhthies ! Thank you for your report.

We are currently having trouble reproducing this in our pipelines. The issue seems to be more related to fmtlib/fmt#3584, which would explain also the temporary fix of reordering/replacing the include. We have bumped up our fmt version to 10.1.1 (commit f969ab6) which contains an upstream fix for this issue.

Could you please check if this solves it on your side?

[mhthies]

Thanks for investigating this issue! :)

You are right: Updating to fmt 10.1.1 fixes the issue. Now, I'll only have to wait for the Arch Linux package maintainer to package this fmt version.