Fixed in r316177.
On Thu, Oct 19, 2017 at 5:57 PM, Benjamin Kramer <benny....@gmail.com> wrote: > We should check VD->getInit()->isValueDependent() before we call > evaluateValue. I wasn't able to come up with a test case that triggers > the assert though :( > > On Thu, Oct 19, 2017 at 5:45 PM, Alexander Kornienko <ale...@google.com> > wrote: >> >> >> On Sat, Oct 14, 2017 at 5:59 PM, Benjamin Kramer via cfe-commits >> <cfe-commits@lists.llvm.org> wrote: >>> >>> Author: d0k >>> Date: Sat Oct 14 08:59:34 2017 >>> New Revision: 315811 >>> >>> URL: http://llvm.org/viewvc/llvm-project?rev=315811&view=rev >>> Log: >>> Re-land r315787, "[Sema] Warn about unused variables if we can constant >>> evaluate the initializer." >>> >>> The warnings in libc++ tests were fixed in the meantime. >>> >>> Modified: >>> cfe/trunk/lib/Sema/SemaDecl.cpp >>> cfe/trunk/test/SemaCXX/warn-unused-variables.cpp >>> >>> Modified: cfe/trunk/lib/Sema/SemaDecl.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=315811&r1=315810&r2=315811&view=diff >>> >>> ============================================================================== >>> --- cfe/trunk/lib/Sema/SemaDecl.cpp (original) >>> +++ cfe/trunk/lib/Sema/SemaDecl.cpp Sat Oct 14 08:59:34 2017 >>> @@ -1723,7 +1723,8 @@ static bool ShouldDiagnoseUnusedDecl(con >>> dyn_cast<CXXConstructExpr>(Init); >>> if (Construct && !Construct->isElidable()) { >>> CXXConstructorDecl *CD = Construct->getConstructor(); >>> - if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>()) >>> + if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>() && >>> + !VD->evaluateValue()) >> >> >> The evaluateValue call above causes an assertion failure on >> instantiation-dependent values: >> llvm/tools/clang/lib/AST/Decl.cpp:2196 in clang::APValue >> *clang::VarDecl::evaluateValue(SmallVectorImpl<clang::PartialDiagnosticAt> >> &) const: !Init->isValueDependent() >> >> I'm not sure why evaluateValue uses an assertion instead of outputting a >> note and returning nullptr, but the assertion can be avoided on the caller >> site as well. >> >> Working on a reduced test case... >> >>> >>> return false; >>> } >>> } >>> >>> Modified: cfe/trunk/test/SemaCXX/warn-unused-variables.cpp >>> URL: >>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-unused-variables.cpp?rev=315811&r1=315810&r2=315811&view=diff >>> >>> ============================================================================== >>> --- cfe/trunk/test/SemaCXX/warn-unused-variables.cpp (original) >>> +++ cfe/trunk/test/SemaCXX/warn-unused-variables.cpp Sat Oct 14 08:59:34 >>> 2017 >>> @@ -1,4 +1,5 @@ >>> // RUN: %clang_cc1 -fsyntax-only -Wunused-variable -Wunused-label >>> -Wno-c++1y-extensions -verify %s >>> +// RUN: %clang_cc1 -fsyntax-only -Wunused-variable -Wunused-label >>> -Wno-c++1y-extensions -verify -std=c++11 %s >>> template<typename T> void f() { >>> T t; >>> t = 17; >>> @@ -194,3 +195,35 @@ void test() { >>> } >>> >>> } >>> + >>> +#if __cplusplus >= 201103L >>> +namespace with_constexpr { >>> +template <typename T> >>> +struct Literal { >>> + T i; >>> + Literal() = default; >>> + constexpr Literal(T i) : i(i) {} >>> +}; >>> + >>> +struct NoLiteral { >>> + int i; >>> + NoLiteral() = default; >>> + constexpr NoLiteral(int i) : i(i) {} >>> + ~NoLiteral() {} >>> +}; >>> + >>> +static Literal<int> gl1; // expected-warning {{unused variable >>> 'gl1'}} >>> +static Literal<int> gl2(1); // expected-warning {{unused variable >>> 'gl2'}} >>> +static const Literal<int> gl3(0); // expected-warning {{unused variable >>> 'gl3'}} >>> + >>> +template <typename T> >>> +void test(int i) { >>> + Literal<int> l1; // expected-warning {{unused variable 'l1'}} >>> + Literal<int> l2(42); // expected-warning {{unused variable 'l2'}} >>> + Literal<int> l3(i); // no-warning >>> + Literal<T> l4(0); // no-warning >>> + NoLiteral nl1; // no-warning >>> + NoLiteral nl2(42); // no-warning >>> +} >>> +} >>> +#endif >>> >>> >>> _______________________________________________ >>> cfe-commits mailing list >>> cfe-commits@lists.llvm.org >>> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits >> >> _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
