Index: Sema/SemaOverload.cpp =================================================================== --- Sema/SemaOverload.cpp +++ Sema/SemaOverload.cpp @@ -7775,11 +7775,13 @@ InitArithmeticTypes(); } + // Increment is deprecated for bool since C++17. + // // C++ [over.built]p3: // - // For every pair (T, VQ), where T is an arithmetic type, and VQ - // is either volatile or empty, there exist candidate operator - // functions of the form + // For every pair (T, VQ), where T is an arithmetic type other + // than bool, and VQ is either volatile or empty, there exist + // candidate operator functions of the form // // VQ T& operator++(VQ T&); // T operator++(VQ T&, int); @@ -7798,8 +7800,12 @@ for (unsigned Arith = 0; Arith < NumArithmeticTypes; ++Arith) { const auto TypeOfT = ArithmeticTypes[Arith]; - if (Op == OO_MinusMinus && TypeOfT == S.Context.BoolTy) - continue; + if (TypeOfT == S.Context.BoolTy) { + if (Op == OO_MinusMinus) + continue; + if (Op == OO_PlusPlus && S.getLangOpts().CPlusPlus17) + continue; + } addPlusPlusMinusMinusStyleOverloads( TypeOfT, VisibleTypeConversionsQuals.hasVolatile(), Index: SemaCXX/overloaded-builtin-operators-cxx17.cpp =================================================================== --- /dev/null +++ SemaCXX/overloaded-builtin-operators-cxx17.cpp @@ -0,0 +1,10 @@ +// RUN: %clang_cc1 -fsyntax-only -fshow-overloads=best -verify -triple x86_64-linux-gnu -std=c++17 %s + +struct BoolRef { + operator bool&(); +}; + +void foo(BoolRef br) { + // C++ [over.built]p3: Increment for bool got deprecated in C++17. + bool b = br++; // expected-error{{cannot increment value of type 'BoolRef'}} +} \ No newline at end of file