[libc-commits] [libc] [libc]: Add -Wextra for libc tests (PR #133643)

[Vinay Deshmukh via libc-commits]

vinay-deshmukh wrote:

@michaelrj-google 

> Overall LGTM, does this also work when building in overlay mode or with gcc?

Unfortunately, I don't have a local gcc install available.

I tried a local overlay build on commit https://github.com/llvm/llvm-project/pull/133643/commits/34accca36ee6a30e17a09aa77774a3274c03c3eb with:

```
❯ cmake -S runtimes \
-B build \
-G Ninja -DLLVM_ENABLE_RUNTIMES="libc"  \
-DCMAKE_EXPORT_COMPILE_COMMANDS=ON \
-DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ \
-DCMAKE_BUILD_TYPE=Debug
```

and 

```
ninja -C build check-libc
```

which passed.


FWIW CI was building until I merged from `main` yesterday. (the gzip error appears unrelated).



https://github.com/llvm/llvm-project/pull/133643