Author: dergachev Date: Thu Feb 15 11:28:21 2018 New Revision: 325284 URL: http://llvm.org/viewvc/llvm-project?rev=325284&view=rev Log: [analyzer] Implement path notes for temporary destructors.
Temporary destructors fire at the end of the full-expression. It is reasonable to attach the path note for entering/leaving the temporary destructor to its CXXBindTemporaryExpr. This would not affect lifetime-extended temporaries with their automatic destructors which aren't temporary destructors. The path note may be confusing in the case of destructors after elidable copy constructors. Differential Revision: https://reviews.llvm.org/D43144 Added: cfe/trunk/test/Analysis/inlining/temp-dtors-path-notes.cpp Modified: cfe/trunk/lib/StaticAnalyzer/Core/PathDiagnostic.cpp Modified: cfe/trunk/lib/StaticAnalyzer/Core/PathDiagnostic.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/StaticAnalyzer/Core/PathDiagnostic.cpp?rev=325284&r1=325283&r2=325284&view=diff ============================================================================== --- cfe/trunk/lib/StaticAnalyzer/Core/PathDiagnostic.cpp (original) +++ cfe/trunk/lib/StaticAnalyzer/Core/PathDiagnostic.cpp Thu Feb 15 11:28:21 2018 @@ -579,8 +579,14 @@ getLocationForCaller(const StackFrameCon const CFGNewAllocator &Alloc = Source.castAs<CFGNewAllocator>(); return PathDiagnosticLocation(Alloc.getAllocatorExpr(), SM, CallerCtx); } - case CFGElement::TemporaryDtor: - llvm_unreachable("not yet implemented!"); + case CFGElement::TemporaryDtor: { + // Temporary destructors are for temporaries. They die immediately at around + // the location of CXXBindTemporaryExpr. If they are lifetime-extended, + // they'd be dealt with via an AutomaticObjectDtor instead. + const auto &Dtor = Source.castAs<CFGTemporaryDtor>(); + return PathDiagnosticLocation::createEnd(Dtor.getBindTemporaryExpr(), SM, + CallerCtx); + } case CFGElement::LifetimeEnds: case CFGElement::LoopExit: llvm_unreachable("CFGElement kind should not be on callsite!"); Added: cfe/trunk/test/Analysis/inlining/temp-dtors-path-notes.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/inlining/temp-dtors-path-notes.cpp?rev=325284&view=auto ============================================================================== --- cfe/trunk/test/Analysis/inlining/temp-dtors-path-notes.cpp (added) +++ cfe/trunk/test/Analysis/inlining/temp-dtors-path-notes.cpp Thu Feb 15 11:28:21 2018 @@ -0,0 +1,64 @@ +// RUN: %clang_analyze_cc1 -analyze -analyzer-checker core -analyzer-config cfg-temporary-dtors=true -analyzer-output=text -verify %s + +namespace test_simple_temporary { +class C { + int x; + +public: + C(int x): x(x) {} // expected-note{{The value 0 is assigned to field 'x'}} + ~C() { x = 1 / x; } // expected-warning{{Division by zero}} + // expected-note@-1{{Division by zero}} +}; + +void test() { + C(0); // expected-note {{Passing the value 0 via 1st parameter 'x'}} + // expected-note@-1{{Calling constructor for 'C'}} + // expected-note@-2{{Returning from constructor for 'C'}} + // expected-note@-3{{Calling '~C'}} +} +} // end namespace test_simple_temporary + +namespace test_lifetime_extended_temporary { +class C { + int x; + +public: + C(int x): x(x) {} // expected-note{{The value 0 is assigned to field 'x'}} + void nop() const {} + ~C() { x = 1 / x; } // expected-warning{{Division by zero}} + // expected-note@-1{{Division by zero}} +}; + +void test(int coin) { + // We'd divide by zero in the temporary destructor that goes after the + // elidable copy-constructor from C(0) to the lifetime-extended temporary. + // So in fact this example has nothing to do with lifetime extension. + // Actually, it would probably be better to elide the constructor, and + // put the note for the destructor call at the closing brace after nop. + const C &c = coin ? C(1) : C(0); // expected-note {{Assuming 'coin' is 0}} + // expected-note@-1{{'?' condition is false}} + // expected-note@-2{{Passing the value 0 via 1st parameter 'x'}} + // expected-note@-3{{Calling constructor for 'C'}} + // expected-note@-4{{Returning from constructor for 'C'}} + // expected-note@-5{{Calling '~C'}} + c.nop(); +} +} // end namespace test_lifetime_extended_temporary + +namespace test_bug_after_dtor { +int glob; + +class C { +public: + C() { glob += 1; } + ~C() { glob -= 2; } // expected-note{{The value 0 is assigned to 'glob'}} +}; + +void test() { + glob = 1; + C(); // expected-note {{Calling '~C'}} + // expected-note@-1{{Returning from '~C'}} + glob = 1 / glob; // expected-warning{{Division by zero}} + // expected-note@-1{{Division by zero}} +} +} // end namespace test_bug_after_dtor _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
