[clang] [clang][sema] Fix crash on class template instantiation when a member variable partial specialization has an invalid primary template (PR #202006)

[Harlen Batagelo via cfe-commits]

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@@ -3623,7 +3623,9 @@ bool Sema::InstantiateClassImpl(
 
     if (Member->isInvalidDecl()) {
       Instantiation->setInvalidDecl();
-      continue;
+      // Keep invalid variable templates for partial specialization lookup.
+      if (!isa<VarTemplateDecl>(Member))
+        continue;
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hbatagelo wrote:

Done.

https://github.com/llvm/llvm-project/pull/202006