[clang] [flang] [Clang][Driver][fveclib] Fix target parsing for -fveclib=AMDLIBM option (PR #140544)

[Paul Walker via cfe-commits]

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@@ -389,7 +389,7 @@ ENUM_CODEGENOPT(Inlining, InliningMethod, 2, NormalInlining)
 VALUE_CODEGENOPT(InlineMaxStackSize, 32, UINT_MAX)
 
 // Vector functions library to use.
-ENUM_CODEGENOPT(VecLib, llvm::driver::VectorLibrary, 3, llvm::driver::VectorLibrary::NoLibrary)
+ENUM_CODEGENOPT(VecLib, llvm::driver::VectorLibrary, 4, llvm::driver::VectorLibrary::NoLibrary)
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paulwalker-arm wrote:

Not sure if there's a compile time way to protect against this in the future, if not then it's worth adding a comment to the matching enum in CodeGenOptions.h to highlight the necessary action of ensuring this value big enough when adding a new library.

https://github.com/llvm/llvm-project/pull/140544