Author: epilk Date: Tue Jul 3 15:15:36 2018 New Revision: 336233 URL: http://llvm.org/viewvc/llvm-project?rev=336233&view=rev Log: [Sema] Discarded statment should be an evaluatable context.
The constexpr evaluator was erroring out because these templates weren't defined. Despite being used in a discarded statement, we still need to constexpr evaluate them, which means that we need to instantiate them. Fixes PR37585. Differential revision: https://reviews.llvm.org/D48322 Modified: cfe/trunk/lib/Sema/SemaExpr.cpp cfe/trunk/test/SemaCXX/constant-expression-cxx1z.cpp Modified: cfe/trunk/lib/Sema/SemaExpr.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaExpr.cpp?rev=336233&r1=336232&r2=336233&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaExpr.cpp (original) +++ cfe/trunk/lib/Sema/SemaExpr.cpp Tue Jul 3 15:15:36 2018 @@ -14237,13 +14237,13 @@ static bool isEvaluatableContext(Sema &S switch (SemaRef.ExprEvalContexts.back().Context) { case Sema::ExpressionEvaluationContext::Unevaluated: case Sema::ExpressionEvaluationContext::UnevaluatedAbstract: - case Sema::ExpressionEvaluationContext::DiscardedStatement: // Expressions in this context are never evaluated. return false; case Sema::ExpressionEvaluationContext::UnevaluatedList: case Sema::ExpressionEvaluationContext::ConstantEvaluated: case Sema::ExpressionEvaluationContext::PotentiallyEvaluated: + case Sema::ExpressionEvaluationContext::DiscardedStatement: // Expressions in this context could be evaluated. return true; Modified: cfe/trunk/test/SemaCXX/constant-expression-cxx1z.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/constant-expression-cxx1z.cpp?rev=336233&r1=336232&r2=336233&view=diff ============================================================================== --- cfe/trunk/test/SemaCXX/constant-expression-cxx1z.cpp (original) +++ cfe/trunk/test/SemaCXX/constant-expression-cxx1z.cpp Tue Jul 3 15:15:36 2018 @@ -46,3 +46,16 @@ namespace Cxx17CD_NB_GB19 { const int &r = 0; constexpr int n = r; } + +namespace PR37585 { +template <class T> struct S { static constexpr bool value = true; }; +template <class T> constexpr bool f() { return true; } +template <class T> constexpr bool v = true; + +void test() { + if constexpr (true) {} + else if constexpr (f<int>()) {} + else if constexpr (S<int>::value) {} + else if constexpr (v<int>) {} +} +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
