[clang] Add clang warning if fp exception functions are called without appropriate flags/pragmas (#128239) (PR #187860)

[Marcos Ramirez Joos via cfe-commits]

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@@ -0,0 +1,55 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -verify=c,expected -DWRONG_FEXCEPT_T %s -ast-dump | FileCheck %s --check-prefixes=CHECK1,CHECK2
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maarcosrmz wrote:

My first though would be to get rid of the explicit C++ tests, since they likely behave similarly to their counterparts in C. Is this option viable? Otherwise I think that I can at most get it down to 6 runs (instead of 8), because we already have implicit usage tests (here the NO_FEGETEXCEPT case) in `fenv-access-implicit.c`.

https://github.com/llvm/llvm-project/pull/187860