sizeof( function )

[Segher Boessenkool]

>> It is invalid to use sizeof() with a function
>> type expression (C99 '6.5.3.4 para. 1) and hence this code invokes
>> undefined behavior.  gcc gives a warning if you compile with 
>> -pedantic,
>> but otherwise it apparently just returns 1;

> But this is actually a BUG in gcc - look at 5.1.1.3.  The restriction
> that sizeof may not have an argument that is function type is a
> constraint, and therefore a breach requires a diagnostic.

There is no bug, as GCC prints a diagnostic just fine.
That's what -pedantic is for.


Segher