On Wed, 2 Nov 2016, Jason Merrill wrote: > It seems to me that the general principle is that we should consider > the location where the thing we're warning about is happening. In > > float_var = LLONG_MIN; > > The relevant location is that of the assignment, not the constant on > the RHS. In your ?: example, a simple answer would be to warn based
I'm not sure we track locations well enough to handle that yet. Say you have an implicit conversion of a function argument to the type from the prototype and something about that conversion should be warned about. Then you should obviously warn if the argument is a macro from a system header but the call is outside a system header. But say the function call itself comes from a macro defined in a system header - you should still warn if the user passed an argument of the wrong type, even if that argument is a macro from a system header. That is: /* System header. */ int __foo (int); /* This sort of macro to avoid accidental interposition issues has been discussed lately on libc-alpha, so it's a realistic example. */ #define foo(x) (0 + __foo (x)) /* User code. */ v = foo (NULL); should warn because the call to __foo logically results from user code even though both NULL and foo are macros defined in system headers. I'm not sure what the locations look like here. -- Joseph S. Myers jos...@codesourcery.com
