[libc-commits] [libc] [libc] `-Wimplicit-fallthrough`, `-Wwrite-strings` and non-GCC warnings (PR #124036)

[Nick Desaulniers via libc-commits]

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@@ -46,13 +46,13 @@ function(_get_common_test_compile_options output_var c_test flags)
       list(APPEND compile_options "-Wno-gnu-imaginary-constant")
     endif()
     list(APPEND compile_options "-Wno-pedantic")
-    # if(NOT CMAKE_COMPILER_IS_GNUCXX)
-    #   list(APPEND compile_options "-Wnewline-eof")
-    #   list(APPEND compile_options "-Wnonportable-system-include-path")
-    #   list(APPEND compile_options "-Wstrict-prototypes")
-    #   list(APPEND compile_options "-Wthread-safety")
-    #   list(APPEND compile_options "-Wglobal-constructors")
-    # endif()
+    if(NOT CMAKE_COMPILER_IS_GNUCXX)
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nickdesaulniers wrote:

If the below command line flags are clang specific, mind changing `NOT CMAKE_COMPILER_IS_GNUCXX` to `CMAKE_CXX_COMPILER_ID STREQUAL "Clang"`?

https://cmake.org/cmake/help/latest/variable/CMAKE_LANG_COMPILER_ID.html

!gcc != clang

even if today we only support those two.

---
`-Wstrict-prototypes` is supported by both compilers, so it should not be in a clang specific list. Rather, it should be enabled for both compilers. Please move it up to the block on L36-L37.

https://github.com/llvm/llvm-project/pull/124036