This breaks the compile of Gnome's soup-0.2.1 on gcc-2.96-93. I haven't 
checked prior versions of gcc.

Messages only occur with -O2 or higher, and only on "C" or "Objective-C" 
compile. C++ compiles are not affected (this has got to be a hint).

[alane@wwweasel alane]$ cat urk.c
extern int is_projectile;
extern void do_distance(), do_quantity();

void urk() {
  if (is_projectile) {
    do_distance();
  } else {
    do_quantity();
  }
}


[alane@wwweasel alane]$ gcc -Wmissing-noreturn -O2 -c urk.c
urk.c: In function `urk':
urk.c:10: warning: function might be possible candidate for attribute 
`noreturn'
[alane@wwweasel alane]$ mv urk.c urk.cc
[alane@wwweasel alane]$ gcc -Wmissing-noreturn -O2 -c urk.cc
[alane@wwweasel alane]$ mv urk.cc urk.m
[alane@wwweasel alane]$ gcc -Wmissing-noreturn -O2 -c urk.m
urk.m: In function `urk':
urk.m:10: warning: function might be possible candidate for attribute 
`noreturn'
[alane@wwweasel alane]$