[clang] [clang] fix crash in friend definition (PR #186398)

[Matheus Izvekov via cfe-commits]

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@@ -18306,6 +18306,14 @@ NamedDecl *Sema::ActOnFriendFunctionDecl(Scope *S, Declarator &D,
   LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
                         RedeclarationKind::ForExternalRedeclaration);
 
+  bool WasQualifiedFriendDef = D.isFunctionDefinition() && SS.isNotEmpty();
+  if (WasQualifiedFriendDef) {
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mizvekov wrote:

nit: we don't need the variable anymore.

https://github.com/llvm/llvm-project/pull/186398