Mandate C90 conformance

[GravisZro]

This PR ensures and enforces C90 conformance for all files C, including tests.

• Modify CMakeLists.txt to mandate C90 conformance (for better compiler compatibility)
• Update deps/ntlmclient/utf8.h to the latest version
• Modify two tests and one header to use C comments instead of C++ comments

[ethomson]

It's strange that only the MemorySanitizer build has trouble with the // comments in the mbedTLS includes.

[ethomson]

It's strange that only the MemorySanitizer build has trouble with the // comments in the mbedTLS includes.

It looks like it’s only a problem on one platform, not sure why, but I’m happy to merge this once it’s working across platforms.

[GravisZro]

It looks like it’s only a problem on one platform, not sure why, but I’m happy to merge this once it’s working across platforms.

I can't figure out how to replicate the memory sanitizer build locally. Is there a script to replicate the automated CI builds?

[ethomson]

Yes — for reproducibility, most of our builds run in containers. For the memory sanitizer build, we use Ubuntu noble, and you can use our pre-built container.

Then you should be able to replicate the build step by setting the appropriate environment variables for the msan build, and running the CI build script.

Something along the lines of:

export CC="clang"
export CFLAGS="-fsanitize=memory -fsanitize-memory-track-origins=2 -fsanitize-blacklist=/home/libgit2/source/script/sanitizers.supp -fno-optimize-sibling-calls -fno-omit-frame-pointer"
export CMAKE_OPTIONS="-DCMAKE_PREFIX_PATH=/usr/local/msan -DUSE_HTTPS=mbedTLS -DUSE_SHA1=HTTPS -DREGEX_BACKEND=pcre -DDEPRECATE_HARD=ON -DUSE_BUNDLED_ZLIB=ON -DUSE_SSH=ON"
export CMAKE_GENERATOR="Ninja"
export SKIP_SSH_TESTS="true"
export SKIP_NEGOTIATE_TESTS="true"
export ASAN_SYMBOLIZER_PATH="/usr/bin/llvm-symbolizer-10"
export UBSAN_OPTIONS="print_stacktrace=1"
/path/to/libgit2/ci/setup-sanitizer-build.sh
/path/to/libgit2/ci/build.sh
/path/to/libgit2/ci/test.sh