https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63732
Bug ID: 63732 Summary: constexpr is not constant expression, when cast member data pointer to data parent type Product: gcc Version: 4.9.2 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: pavel.kral at omsquare dot com The code bellow returns error on 4.9.2 (and cause ICE on 4.8.x) tested on Linux, MinGW and arm-none-eabi. While 'xxx' compiles just fine, 'yyy' which is casted to parent type doesn't. Just for clarification static const array 'm_members' compiles fine and generate values at compile time in .rodata section as expected (arm-none-eabi). class PropertyBase {}; class Number : PropertyBase {}; class ComplexProperty : PropertyBase { public: Number m_firstNumber; static PropertyBase ComplexProperty::* const m_members[]; // compiles fine static constexpr auto xxx = (Number ComplexProperty::*)&ComplexProperty::m_firstNumber; // error: '(PropertyBase ComplexProperty::*)&ComplexProperty::m_firstNumber' is not a constant expression static constexpr auto yyy = (PropertyBase ComplexProperty::*)&ComplexProperty::m_firstNumber; }; // compiles fine PropertyBase ComplexProperty::* const ComplexProperty::m_members[] = { (PropertyBase ComplexProperty::*) &ComplexProperty::m_firstNumber }; static ComplexProperty person; int main() { }