[clang] [clang] Reapply Handle templated operators with reversed arguments (PR #72213)

[Utkarsh Saxena via cfe-commits]

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@@ -10088,9 +10088,13 @@ static bool allowAmbiguity(ASTContext &Context, const FunctionDecl *F1,
                            const FunctionDecl *F2) {
   if (declaresSameEntity(F1, F2))
     return true;
-  if (F1->isTemplateInstantiation() && F2->isTemplateInstantiation() &&
-      declaresSameEntity(F1->getPrimaryTemplate(), F2->getPrimaryTemplate())) {
-    return true;
+  if (F1->isTemplateInstantiation() && F2->isTemplateInstantiation()) {
+    auto PT1 = F1->getPrimaryTemplate();
+    auto PT2 = F2->getPrimaryTemplate();
+    if (declaresSameEntity(PT1, PT2) ||
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usx95 wrote:

Fixed the crash. For some reason, the example is not ambiguous in any compiler https://godbolt.org/z/Gs34eo9cf. Trying to come up with a test case..

https://github.com/llvm/llvm-project/pull/72213