[clang] [clang] Implement function pointer type discrimination (PR #96992)

[Daniil Kovalev via cfe-commits]

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@@ -470,6 +470,9 @@ ENUM_LANGOPT(StrictFlexArraysLevel, StrictFlexArraysLevelKind, 2,
 
 COMPATIBLE_VALUE_LANGOPT(MaxTokens, 32, 0, "Max number of tokens per TU or 0")
 
+BENIGN_LANGOPT(FunctionPointerTypeDiscrimination, 1, 0,
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kovdan01 wrote:

Can we use `LANGOPT`, just as we use for other similar `PointerAuth*` options above? Also, moving this definition to similar ones would probably make sense.

https://github.com/llvm/llvm-project/pull/96992