From: utzoo!henry
Newsgroups: net.lang.c
Title: Re: C and real hardware 
Article-I.D.: utzoo.2937
Posted: Thu Apr 28 19:54:08 1983
Received: Thu Apr 28 19:54:08 1983

The old BLISS-11 compiler had an elaborate set of constructs for telling
the compiler what could and could not be safely assumed for purposes of
optimization.  For example, I think there was a way you could convince
it not to optimize a wait-on-device-register-bit loop into one register
access and an infinite loop.  It's rather unfortunate that C compilers
generally have not attempted enough optimization to run into these
problems.  Just how one solves them cleanly in C is not obvious.

					Henry Spencer
					U of Toronto