On 08/22/2014 01:53 PM, Paolo Carlini wrote:
maybe this old issue is already fixed. We used to ICE on:typedef void (*fptr)() __attribute((noreturn)); template<int> void foo(); template<fptr> void bar(); fptr f = bar< foo<0> >; but lately we simply reject it: 34938.C:5:10: error: no matches converting function ‘bar’ to type ‘fptr {aka void (*)() volatile}’ fptr f = bar< foo<0> >; ^ 34938.C:3:21: note: candidate is: template<void (* <anonymous>)() volatile> void bar() template<fptr> void bar(); ^ is that Ok? clang behaves like us, EDG accepts the code.
Well, since the attribute is outside the language, I guess we get to decide what it means; C++11 [[noreturn]] is only defined on decls, not types.
I think rejecting it makes sense; since bar is not declared as noreturn, assigning its address to a noreturn function pointer seems wrong.
A secondary issue I noticed is that we print 'volatile' instead of the attribute, that is fixed by the patchlet below.
Currently function-cv-quals on a FUNCTION_TYPE used as a typedef or template parameter have the same encoding as the const and noreturn attributes; to get the printing right you need to know the context of the FUNCTION_TYPE. If it's the type of a pointer, then the attribute is correct.
Jason
