Author: Krystian Stasiowski Date: 2024-02-26T14:01:48-05:00 New Revision: ce4740d3e31e936aa93c115f63bf223c74c9dc20
URL: https://github.com/llvm/llvm-project/commit/ce4740d3e31e936aa93c115f63bf223c74c9dc20 DIFF: https://github.com/llvm/llvm-project/commit/ce4740d3e31e936aa93c115f63bf223c74c9dc20.diff LOG: [Clang][Sema] Fix crash when MS dependent base class lookup occurs in an incomplete context (#83024) When compiling the following with `-fms-compatibility`: ``` template<typename T> struct C; // Test lookup with incomplete lookup context template<typename T> auto C<T>::f() -> decltype(x) { } ``` An assert fails because `CXXRecordDecl::hasAnyDependentBases` is called on an incomplete class. This patch ensures we don't perform unqualified lookup into dependent base classes when the lookup context is incomplete. Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/Sema/SemaExpr.cpp clang/test/SemaTemplate/ms-lookup-template-base-classes.cpp Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 9e67bbb7895040..515dffa28df186 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -283,6 +283,8 @@ Bug Fixes to C++ Support (`#78524 <https://github.com/llvm/llvm-project/issues/78524>`_) - Clang no longer instantiates the exception specification of discarded candidate function templates when determining the primary template of an explicit specialization. +- Fixed a crash in Microsoft compatibility mode where unqualified dependent base class + lookup searches the bases of an incomplete class. Bug Fixes to AST Handling ^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index 816ee9e281359a..403839f77a2b7c 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -2653,7 +2653,7 @@ recoverFromMSUnqualifiedLookup(Sema &S, ASTContext &Context, RD = ThisType->getPointeeType()->getAsCXXRecordDecl(); else if (auto *MD = dyn_cast<CXXMethodDecl>(S.CurContext)) RD = MD->getParent(); - if (!RD || !RD->hasAnyDependentBases()) + if (!RD || !RD->hasDefinition() || !RD->hasAnyDependentBases()) return nullptr; // Diagnose this as unqualified lookup into a dependent base class. If 'this' diff --git a/clang/test/SemaTemplate/ms-lookup-template-base-classes.cpp b/clang/test/SemaTemplate/ms-lookup-template-base-classes.cpp index 7856a0a16307be..534a5dc9ddc10d 100644 --- a/clang/test/SemaTemplate/ms-lookup-template-base-classes.cpp +++ b/clang/test/SemaTemplate/ms-lookup-template-base-classes.cpp @@ -71,6 +71,13 @@ class B : public A<T> { template class B<int>; +template<typename T> struct C; + +// Test lookup with incomplete lookup context +template<typename T> +auto C<T>::f() -> decltype(x) { } // expected-error {{use of undeclared identifier 'x'}} + // expected-error@-1 {{out-of-line definition of 'f' from class 'C<T>' without definition}} + } _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
