[clang] Honor pragmas with -ffp-contract=fast, depecate fast-honor-pragmas (PR #105746)

[Fangrui Song via cfe-commits]

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@@ -30,8 +29,10 @@
 // RUN:   | FileCheck --check-prefix=CHECK-FPC-FAST %s
 
 // RUN: %clang -### -ffast-math -ffp-contract=fast-honor-pragmas -c %s 2>&1 \
-// RUN:   | FileCheck --check-prefixes=CHECK-FPC-FAST-HONOR,WARN_FM_FHP %s
-// CHECK-FPC-FAST-HONOR:     "-ffp-contract=fast-honor-pragmas"
+// RUN:   | FileCheck --check-prefixes=CHECK-FPC-FAST-HONOR,WARN_FHP_DEPRECATED %s
+// WARN_FHP_DEPRECATED: clang: warning: argument '-ffp-contract=fast-honor-pragmas' is deprecated, use '-ffp-contract=fast' instead [-Wdeprecated]
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MaskRay wrote:

We generally don't check the string before "warning" (can be customized)

https://github.com/llvm/llvm-project/pull/105746