[Mlir-commits] [mlir] [MLIR][CMake] Suppress -Wpass-failed warning (PR #160472)

[Mehdi Amini]

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@@ -110,6 +110,12 @@ if(CMAKE_CXX_COMPILER_ID MATCHES "GNU")
   endif()
 endif()
 
+# libstdc++15 makes use of an unroll pragma inside std::find_if(). This
+# produces a warning if clang fails to unroll the loop. As this pragma is
+# outside of our control, suppress the warning.
+check_cxx_compiler_flag("-Wno-pass-failed" CXX_SUPPORTS_WNO_PASS_FAILED)
+append_if(CXX_SUPPORTS_WNO_PASS_FAILED "-Wno-pass-failed" CMAKE_CXX_FLAGS)
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joker-eph wrote:

It's not clear to me why is this the right fix.
This seems like a workaround for a specific version of the toolchain, but  doesn't this point out to a problem with the warning itself? 
Either the warning should be opt-in, or it should be able to maybe not hit on system headers (which I don't see how do implement in a robust way)?



https://github.com/llvm/llvm-project/pull/160472