release/21.x: [Clang] Fix an error-recovery crash after d1a80dea (#159976)

[llvmbot]

Backport 90a6b00

Requested by: @zyn0217

[llvmbot]

@cor3ntin What do you think about merging this PR to the release branch?

[llvmbot]

@llvm/pr-subscribers-clang

Author: None (llvmbot)

Changes

Backport 90a6b00

Requested by: @zyn0217

---

Full diff: https://github.com/llvm/llvm-project/pull/159980.diff

2 Files Affected:

• (modified) clang/lib/Sema/SemaExprCXX.cpp (+2)
• (modified) clang/test/SemaTemplate/destructor-template.cpp (+15)

diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 25afa2f4dfe7a..a08971c6526fe 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -347,6 +347,8 @@ ParsedType Sema::getDestructorName(const IdentifierInfo &II,
         CheckTypenameType(ElaboratedTypeKeyword::None, SourceLocation(),
                           SS.getWithLocInContext(Context), II, NameLoc, &TSI,
                           /*DeducedTSTContext=*/true);
+    if (T.isNull())
+      return ParsedType();
     return CreateParsedType(T, TSI);
   }
 
diff --git a/clang/test/SemaTemplate/destructor-template.cpp b/clang/test/SemaTemplate/destructor-template.cpp
index 7a3398308bbee..734269e854e5d 100644
--- a/clang/test/SemaTemplate/destructor-template.cpp
+++ b/clang/test/SemaTemplate/destructor-template.cpp
@@ -104,3 +104,18 @@ struct T : S {
   ~T() = default;
 };
 } // namespace PR38671
+
+namespace GH159630 {
+
+struct X {
+  template<typename T>
+  struct typo { // expected-note {{'typo' declared here}}
+    ~typo();
+  };
+};
+
+template<typename T>
+X::typo<T>::typ0::~typ0() {} // expected-error {{no member named 'typ0'}} \
+                             // expected-error {{no type named 'typ0'}}
+
+}

[github-actions]

@zyn0217 (or anyone else). If you would like to add a note about this fix in the release notes (completely optional). Please reply to this comment with a one or two sentence description of the fix. When you are done, please add the release:note label to this PR.