Author: Fabian Wolff Date: 2021-11-15T07:41:35Z New Revision: c3e3c762098e8d425731bb40f3b8b04dac1013f3
URL: https://github.com/llvm/llvm-project/commit/c3e3c762098e8d425731bb40f3b8b04dac1013f3 DIFF: https://github.com/llvm/llvm-project/commit/c3e3c762098e8d425731bb40f3b8b04dac1013f3.diff LOG: [clang-tidy] Fix `bugprone-use-after-move` check to also consider moves in constructor initializers Fixes PR#38187. Constructors are actually already checked, but only as functions, i.e. the check only looks at the constructor body and not at the initializers, which misses the (common) case where constructor parameters are moved as part of an initializer expression. One remaining false negative is when both the move //and// the use-after-move occur in constructor initializers. This is a lot more difficult to handle, though, because the `bugprone-use-after-move` check is currently based on a CFG that only takes the body into account, not the initializers, so e.g. initialization order would have to manually be considered. I will file a follow-up issue for this once PR#38187 is closed. Reviewed By: carlosgalvezp Differential Revision: https://reviews.llvm.org/D113708 Added: Modified: clang-tools-extra/clang-tidy/bugprone/UseAfterMoveCheck.cpp clang-tools-extra/test/clang-tidy/checkers/bugprone-use-after-move.cpp Removed: ################################################################################ diff --git a/clang-tools-extra/clang-tidy/bugprone/UseAfterMoveCheck.cpp b/clang-tools-extra/clang-tidy/bugprone/UseAfterMoveCheck.cpp index 136d8f862b956..064b6ae19784e 100644 --- a/clang-tools-extra/clang-tidy/bugprone/UseAfterMoveCheck.cpp +++ b/clang-tools-extra/clang-tidy/bugprone/UseAfterMoveCheck.cpp @@ -129,8 +129,12 @@ bool UseAfterMoveFinder::find(Stmt *FunctionBody, const Expr *MovingCall, Visited.clear(); const CFGBlock *Block = BlockMap->blockContainingStmt(MovingCall); - if (!Block) - return false; + if (!Block) { + // This can happen if MovingCall is in a constructor initializer, which is + // not included in the CFG because the CFG is built only from the function + // body. + Block = &TheCFG->getEntry(); + } return findInternal(Block, MovingCall, MovedVariable, TheUseAfterMove); } diff --git a/clang-tools-extra/test/clang-tidy/checkers/bugprone-use-after-move.cpp b/clang-tools-extra/test/clang-tidy/checkers/bugprone-use-after-move.cpp index 73ca59ccc91bf..e26db0f6793e0 100644 --- a/clang-tools-extra/test/clang-tidy/checkers/bugprone-use-after-move.cpp +++ b/clang-tools-extra/test/clang-tidy/checkers/bugprone-use-after-move.cpp @@ -1338,3 +1338,15 @@ void typeId() { Foo Other{std::move(Bar)}; } } // namespace UnevalContext + +class PR38187 { +public: + PR38187(std::string val) : val_(std::move(val)) { + val.empty(); + // CHECK-NOTES: [[@LINE-1]]:5: warning: 'val' used after it was moved + // CHECK-NOTES: [[@LINE-3]]:30: note: move occurred here + } + +private: + std::string val_; +}; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits