[clang] [Clang] Separate implicit int conversion on negation sign to new diagnostic group (PR #139429)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,64 @@
+// RUN: %clang_cc1 %s -verify -Wimplicit-int-conversion
+// RUN: %clang_cc1 %s -verify -Wimplicit-int-conversion -Wno-implicit-int-conversion-on-negation -DNO_DIAG
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AaronBallman wrote:

A better approach than using `-D` is to specify a prefix to `-verify`: https://clang.llvm.org/docs/InternalsManual.html#verifying-diagnostics

Then you can have one comment for the `-no-diagnostics` RUN line and skip all the preprocessor code for the other RUN line.

https://github.com/llvm/llvm-project/pull/139429