[llvm] [DirectX] Error handling improve in root signature metadata Parser (PR #149232)

[Chris B via llvm-commits]

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@@ -22,42 +21,34 @@ namespace llvm {
 namespace hlsl {
 namespace rootsig {
 
-static std::optional<uint32_t> extractMdIntValue(MDNode *Node,
+char GenericRSMetadataError::ID;
+char InvalidRSMetadataFormat::ID;
+char InvalidRSMetadataValue::ID;
+template <typename T> char RootSignatureValidationError<T>::ID;
+
+inline std::optional<uint32_t> extractMdIntValue(MDNode *Node,
                                                  unsigned int OpId) {
   if (auto *CI =
           mdconst::dyn_extract<ConstantInt>(Node->getOperand(OpId).get()))
     return CI->getZExtValue();
   return std::nullopt;
 }
 
-static std::optional<float> extractMdFloatValue(MDNode *Node,
+inline std::optional<float> extractMdFloatValue(MDNode *Node,
----------------
llvm-beanz wrote:

`static` and `inline` aren't strictly equivalent. The `inline` keyword doesn't impact symbol visibility, so this function is still exported and externally visible. It becomes an ODR so if there are multiple definitions they must all be identical, but that's not the behavior we want.

See the relevant coding standard: https://llvm.org/docs/CodingStandards.html#restrict-visibility

https://github.com/llvm/llvm-project/pull/149232