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

[Vinay Deshmukh via libc-commits]

vinay-deshmukh wrote:

@lntue @nickdesaulniers 

Any suggestions on how I can diagnose the `illegal instruction, core dumped` further?

```
[==========] Running 6 tests from 1 test suite.
[ RUN      ] LlvmLibcMemcmpTest.CmpZeroByte
[       OK ] LlvmLibcMemcmpTest.CmpZeroByte (3 us)
[ RUN      ] LlvmLibcMemcmpTest.LhsRhsAreTheSame
[       OK ] LlvmLibcMemcmpTest.LhsRhsAreTheSame (1 us)
[ RUN      ] LlvmLibcMemcmpTest.LhsBeforeRhsLexically
[       OK ] LlvmLibcMemcmpTest.LhsBeforeRhsLexically (0 ns)
[ RUN      ] LlvmLibcMemcmpTest.LhsAfterRhsLexically
[       OK ] LlvmLibcMemcmpTest.LhsAfterRhsLexically (1 us)
[ RUN      ] LlvmLibcMemcmpTest.Issue77080
[       OK ] LlvmLibcMemcmpTest.Issue77080 (0 ns)
[ RUN      ] LlvmLibcMemcmpTest.SizeSweep
Illegal instruction (core dumped)
[5720/6613] Running unit test libc.test.src.string.memcmp_test.__unit__
FAILED: libc/test/src/string/CMakeFiles/libc.test.src.string.memcmp_test.__unit__ /home/runner/work/llvm-project/llvm-project/build/libc/test/src/string/CMakeFiles/libc.test.src.string.memcmp_test.__unit__ 
cd /home/runner/work/llvm-project/llvm-project/build/libc/test/src/string && /home/runner/work/llvm-project/llvm-project/build/libc/test/src/string/libc.test.src.string.memcmp_test.__unit__.__build__
[==========] Running 6 tests from 1 test suite.
[ RUN      ] LlvmLibcMemcmpTest.CmpZeroByte
[       OK ] LlvmLibcMemcmpTest.CmpZeroByte (2 us)
[ RUN      ] LlvmLibcMemcmpTest.LhsRhsAreTheSame
[       OK ] LlvmLibcMemcmpTest.LhsRhsAreTheSame (1 us)
[ RUN      ] LlvmLibcMemcmpTest.LhsBeforeRhsLexically
[       OK ] LlvmLibcMemcmpTest.LhsBeforeRhsLexically (0 ns)
[ RUN      ] LlvmLibcMemcmpTest.LhsAfterRhsLexically
[       OK ] LlvmLibcMemcmpTest.LhsAfterRhsLexically (0 ns)
[ RUN      ] LlvmLibcMemcmpTest.Issue77080
[       OK ] LlvmLibcMemcmpTest.Issue77080 (1 us)
[ RUN      ] LlvmLibcMemcmpTest.SizeSweep
Illegal instruction (core dumped)
[5721/6613] Building CXX object libc/test/src/strings/CMakeFiles/libc.test.src.strings.ffs_test.__unit__.__build__.dir/ffs_test.cpp.o
```

I'm unable to do a full build on Macbook m1, overlay build did pass successfully FWIW

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