expressions and #if

[guy at rlgvax.UUCP]

"cpp" doesn't support "sizeof" in #if expressions; it would be nice, but
would also mean that "cpp" would have to swallow a good deal more of C's
grammar, would have to know what machine it was running on, and would have
to parse all "typedef" statements that passed by it - in effect, it would
have to absorb a good deal of the C compiler.  A C compiler with macro
expansion built into it might be better able to support "sizeof" in #if.

	Guy Harris
	{seismo,ihnp4,allegra}!rlgvax!guy