[Bug libstdc++/57691] freestanding libstdc++ has compile error

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57691

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Paolo Carlini from comment #4)
> ... by the way, I'm *very* surprised that nobody noticed this over the
> years: the freestanding atexit is declared like this in <cstdlib> in 4.0.0!?!

It only matters on some less-well-tested targets, because NO_IMPLICIT_EXTERN_C
is defined for sane targets.  It might also not matter if the system headers
declare:
    int atexit(void (*)(void));
as GNU Libc does, because then the function is declared portably for both C and
C++.

Presumably the eCos headers either don't declare atexit or declare it without
an abominable (void) parameter list.