[clang] [clang] Track function template instantiation from definition (PR #110387)

[Younan Zhang via cfe-commits]

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@@ -1008,6 +1008,15 @@ class FunctionTemplateDecl : public RedeclarableTemplateDecl {
     return getTemplatedDecl()->isThisDeclarationADefinition();
   }
 
+  bool isCompatibleWithDefinition() const {
+    return getTemplatedDecl()->isInstantiatedFromMemberTemplate() ||
+           isThisDeclarationADefinition();
+  }
+  void setInstantiatedFromMemberTemplate(FunctionTemplateDecl *D) {
+    getTemplatedDecl()->setInstantiatedFromMemberTemplate();
+    RedeclarableTemplateDecl::setInstantiatedFromMemberTemplate(D);
+  }
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zyn0217 wrote:

So the flag on FunctionDecl now appears to be just a shortcut of getDescribedTemplate()->getInstantiatedFromMemberTemplate(), or am I missing something else?

https://github.com/llvm/llvm-project/pull/110387