#pragma in gcc

When the ANSI C standard was under development, thepragma directive was introduced. Borrowed from Ada, #pragmais used to convey hints to the compiler, such as the desireto expand a particular function as in-line or suppress somerange checks. #pragma met with some initial resistancee froma gcc implementor, who took the "implementation-defined" effectvery literally. In gcc version 1.34, the use of pragma causedthe compiler to stop compiling and launch a computer game instead.The gcc version 1.34 manual said:

"The #pragma command is specified in the ANSI standard to havean arbitrary implementation-defined effect. In GNU C preprocessor,#pragma first attempts to run the game "rogue"; if that fails,it tries to run the game "hack"; if that fails, it tries to runGNU Emacs displaying Tower Of Hanoi; if that fails, it reportsa fatal error. In any case, preprocessing does not continue."

Here's an excerpt from the gcc source, version 1.35,released in 1989 (note the "#if 0"):

#if 0
/* This was a fun hack, but #pragma seems to start to be useful.
   By failing to recognize it, we pass it through unchanged to cc1. */

/*
 * the behavior of the #pragma directive is implementation defined.
 * this implementation defines it as follows.
 */
do_pragma ()
{
    close (0);
    if (open ("/dev/tty", O_RDONLY, 0666) != 0)
        goto nope;
    close (1);
    if (open ("/dev/tty", O_WRONLY, 0666) != 1)
        goto nope;
    execl ("/usr/games/hack", "#pragma", 0);
    execl ("/usr/games/rogue", "#pragma", 0);
    execl ("/usr/new/emacs", "-f", "hanoi", "9", "-kill", 0);
    execl ("/usr/local/emacs", "-f", "hanoi", "9", "-kill", 0);
nope:
    fatal ("You are in a maze of twisty compiler features, all different");
}
#endif