[clang] [clang] fix getReplacedTemplateParameter for function template specializations (PR #189559)

[Matheus Izvekov via cfe-commits]

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@@ -1707,10 +1707,12 @@ clang::getReplacedTemplateParameter(Decl *D, unsigned Index) {
   case Decl::Kind::CXXConstructor:
   case Decl::Kind::CXXDestructor:
   case Decl::Kind::CXXMethod:
-  case Decl::Kind::Function:
-    return getReplacedTemplateParameter(
-        cast<FunctionDecl>(D)->getTemplateSpecializationInfo()->getTemplate(),
-        Index);
+  case Decl::Kind::Function: {
+    const FunctionTemplateSpecializationInfo *Info =
+        cast<FunctionDecl>(D)->getTemplateSpecializationInfo();
+    return {Info->getTemplate()->getTemplateParameters()->getParam(Index),
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mizvekov wrote:

You mean this function? I am confused.

https://github.com/llvm/llvm-project/pull/189559