Author: Ryosuke Niwa Date: 2025-04-10T15:28:36-07:00 New Revision: 613601978073058f4a4620e93bb84ac8f387934a
URL: https://github.com/llvm/llvm-project/commit/613601978073058f4a4620e93bb84ac8f387934a DIFF: https://github.com/llvm/llvm-project/commit/613601978073058f4a4620e93bb84ac8f387934a.diff LOG: [alpha.webkit.ForwardDeclChecker] Recognize a forward declared template specialization (#134545) This PR fixes a bug that when a template specialization is declared with a forward declaration of a template, the checker fails to find its definition in the same translation unit and erroneously emit an unsafe forward declaration warning. Added: Modified: clang/lib/StaticAnalyzer/Checkers/WebKit/ForwardDeclChecker.cpp clang/test/Analysis/Checkers/WebKit/forward-decl-checker.mm Removed: ################################################################################ diff --git a/clang/lib/StaticAnalyzer/Checkers/WebKit/ForwardDeclChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/WebKit/ForwardDeclChecker.cpp index 0d2c3bc53b085..a216d9abc4f76 100644 --- a/clang/lib/StaticAnalyzer/Checkers/WebKit/ForwardDeclChecker.cpp +++ b/clang/lib/StaticAnalyzer/Checkers/WebKit/ForwardDeclChecker.cpp @@ -126,8 +126,18 @@ class ForwardDeclChecker : public Checker<check::ASTDecl<TranslationUnitDecl>> { if (!R) // Forward declaration of a Objective-C interface is safe. return false; auto Name = R->getName(); - return !R->hasDefinition() && !RTC.isUnretained(QT) && - !SystemTypes.contains(CanonicalType) && + if (R->hasDefinition()) + return false; + // Find a definition amongst template declarations. + if (auto *Specialization = dyn_cast<ClassTemplateSpecializationDecl>(R)) { + if (auto *S = Specialization->getSpecializedTemplate()) { + for (S = S->getMostRecentDecl(); S; S = S->getPreviousDecl()) { + if (S->isThisDeclarationADefinition()) + return false; + } + } + } + return !RTC.isUnretained(QT) && !SystemTypes.contains(CanonicalType) && !SystemTypes.contains(PointeeType) && !Name.starts_with("Opaque") && Name != "_NSZone"; } diff --git a/clang/test/Analysis/Checkers/WebKit/forward-decl-checker.mm b/clang/test/Analysis/Checkers/WebKit/forward-decl-checker.mm index 64100d60c4867..084b47322d7f9 100644 --- a/clang/test/Analysis/Checkers/WebKit/forward-decl-checker.mm +++ b/clang/test/Analysis/Checkers/WebKit/forward-decl-checker.mm @@ -138,3 +138,20 @@ - (void)doMoreWork:(ObjCObj *)obj { } @end + +namespace template_forward_declare { + +template<typename> class HashSet; + +template<typename T> +using SingleThreadHashSet = HashSet<T>; + +template<typename> class HashSet { }; + +struct Font { }; + +struct ComplexTextController { + SingleThreadHashSet<const Font>* fallbackFonts { nullptr }; +}; + +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
