diff --git a/clang/lib/Analysis/CFG.cpp b/clang/lib/Analysis/CFG.cpp index 94c005f55214..315e54380b2f 100644 --- a/clang/lib/Analysis/CFG.cpp +++ b/clang/lib/Analysis/CFG.cpp @@ -1648,8 +1648,10 @@ CFGBlock *CFGBuilder::VisitDeclSubExpr(DeclStmt *DS) { // If the type of VD is a VLA, then we must process its size expressions. for (const VariableArrayType* VA = FindVA(VD->getType().getTypePtr()); - VA != 0; VA = FindVA(VA->getElementType().getTypePtr())) - Block = addStmt(VA->getSizeExpr()); + VA != 0; VA = FindVA(VA->getElementType().getTypePtr())) { + if (CFGBlock *newBlock = addStmt(VA->getSizeExpr())) + LastBlock = newBlock; + } // Remove variable from local scope. if (ScopePos && VD == *ScopePos) @@ -1767,7 +1769,7 @@ CFGBlock *CFGBuilder::VisitIfStmt(IfStmt *I) { // Add the condition as the last statement in the new block. This may create // new blocks as the condition may contain control-flow. Any newly created // blocks will be pointed to be "Block". - Block = addStmt(I->getCond()); + CFGBlock *LastBlock = addStmt(I->getCond()); // Finally, if the IfStmt contains a condition variable, add both the IfStmt // and the condition variable initialization to the CFG. @@ -1775,11 +1777,11 @@ CFGBlock *CFGBuilder::VisitIfStmt(IfStmt *I) { if (Expr *Init = VD->getInit()) { autoCreateBlock(); appendStmt(Block, I->getConditionVariableDeclStmt()); - addStmt(Init); + LastBlock = addStmt(Init); } } - return Block; + return LastBlock; } @@ -2611,7 +2613,7 @@ CFGBlock *CFGBuilder::VisitSwitchStmt(SwitchStmt *Terminator) { // Add the terminator and condition in the switch block. SwitchTerminatedBlock->setTerminator(Terminator); Block = SwitchTerminatedBlock; - Block = addStmt(Terminator->getCond()); + CFGBlock *LastBlock = addStmt(Terminator->getCond()); // Finally, if the SwitchStmt contains a condition variable, add both the // SwitchStmt and the condition variable initialization to the CFG. @@ -2619,11 +2621,11 @@ CFGBlock *CFGBuilder::VisitSwitchStmt(SwitchStmt *Terminator) { if (Expr *Init = VD->getInit()) { autoCreateBlock(); appendStmt(Block, Terminator->getConditionVariableDeclStmt()); - addStmt(Init); + LastBlock = addStmt(Init); } } - return Block; + return LastBlock; } static bool shouldAddCase(bool &switchExclusivelyCovered, @@ -2807,8 +2809,7 @@ CFGBlock *CFGBuilder::VisitCXXTryStmt(CXXTryStmt *Terminator) { assert(Terminator->getTryBlock() && "try must contain a non-NULL body"); Block = NULL; - Block = addStmt(Terminator->getTryBlock()); - return Block; + return addStmt(Terminator->getTryBlock()); } CFGBlock *CFGBuilder::VisitCXXCatchStmt(CXXCatchStmt *CS) { @@ -2949,15 +2950,15 @@ CFGBlock *CFGBuilder::VisitCXXForRangeStmt(CXXForRangeStmt *S) { addLocalScopeAndDtors(S->getLoopVarStmt()); // Populate a new block to contain the loop body and loop variable. - Block = addStmt(S->getBody()); + addStmt(S->getBody()); if (badCFG) return 0; - Block = addStmt(S->getLoopVarStmt()); + CFGBlock *LoopVarStmtBlock = addStmt(S->getLoopVarStmt()); if (badCFG) return 0; // This new body block is a successor to our condition block. - addSuccessor(ConditionBlock, KnownVal.isFalse() ? 0 : Block); + addSuccessor(ConditionBlock, KnownVal.isFalse() ? 0 : LoopVarStmtBlock); } // Link up the condition block with the code that follows the loop (the diff --git a/clang/test/Analysis/dead-stores.cpp b/clang/test/Analysis/dead-stores.cpp index 341363afaa8f..86d84f0fbfa4 100644 --- a/clang/test/Analysis/dead-stores.cpp +++ b/clang/test/Analysis/dead-stores.cpp @@ -126,3 +126,26 @@ int test_5() { return 1; } + +int test_6_aux(unsigned x); + +void test_6() { + unsigned currDestLen = 0; // no-warning + try { + while (test_6_aux(currDestLen)) { + currDestLen += 2; // no-warning + } + } + catch (void *) {} +} + +void test_6b() { + unsigned currDestLen = 0; // no-warning + try { + while (test_6_aux(currDestLen)) { + currDestLen += 2; // expected-warning {{Value stored to 'currDestLen' is never read}} + break; + } + } + catch (void *) {} +}