diff --git a/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp b/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp index f2b4a67e5bc97b..3f1600d9ac5d87 100644 --- a/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp +++ b/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp @@ -419,7 +419,11 @@ class ResultObjectVisitor : public RecursiveASTVisitor { // below them can initialize the same object (or part of it). if (isa(E) || isa(E) || isa(E) || isa(E) || isa(E) || - isa(E)) { + isa(E) || + // We treat `BuiltinBitCastExpr` as an "original initializer" too as + // it may not even be casting from a record type -- and even if it is, + // the two objects are in general of unrelated type. + isa(E)) { return; } if (auto *Op = dyn_cast(E); diff --git a/clang/unittests/Analysis/FlowSensitive/TransferTest.cpp b/clang/unittests/Analysis/FlowSensitive/TransferTest.cpp index d7a51b009712f6..97ec32126c1dc4 100644 --- a/clang/unittests/Analysis/FlowSensitive/TransferTest.cpp +++ b/clang/unittests/Analysis/FlowSensitive/TransferTest.cpp @@ -3208,6 +3208,32 @@ TEST(TransferTest, ResultObjectLocationForStmtExpr) { }); } +TEST(TransferTest, ResultObjectLocationForBuiltinBitCastExpr) { + std::string Code = R"( + struct S { int i; }; + void target(int i) { + S s = __builtin_bit_cast(S, i); + // [[p]] + } + )"; + using ast_matchers::explicitCastExpr; + using ast_matchers::match; + using ast_matchers::selectFirst; + using ast_matchers::traverse; + runDataflow( + Code, + [](const llvm::StringMap> &Results, + ASTContext &ASTCtx) { + const Environment &Env = getEnvironmentAtAnnotation(Results, "p"); + + auto *BuiltinBitCast = selectFirst( + "cast", match(explicitCastExpr().bind("cast"), ASTCtx)); + + EXPECT_EQ(&Env.getResultObjectLocation(*BuiltinBitCast), + &getLocForDecl(ASTCtx, Env, "s")); + }); +} + TEST(TransferTest, ResultObjectLocationPropagatesThroughConditionalOperator) { std::string Code = R"( struct A {