bitfields considered harmful?

[Christoph Kuenkel]

We have some software using C bitfields like in

	struct ... {
		unsigned	active : 1,
				waiting : 1;
		...
	};

During various ports of that to different SysV machines (should i have posted
that to comp.unix.wizards?) we ran into problems because of compiler bugs.
One time, assembler code was produced that tried to shift a word 0 bits to the
right (68020), another time bitfields read nonzero all the time (iapx386), as
in
	if (x.active) { /* always done */ } else { /* dead code */ }

Now, are bitfields generally considered harmfull?  Are there other good
reasons to avoid them? what does ANSI C say about it?

I like them cause they save space and are much more readable than 
oriing/anding with # defines and i dont have to bother with questions like
how many flags fit into one int.

thanx, christoph
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