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Re: Serious error-causing change in new CPP's -traditional behavior
On Wed, May 10, 2000 at 10:05:33AM -0700, Zack Weinberg wrote:
> > '#' introduces an immediate constant in the assembler syntax; removing it
> > is bogus, and worse, there is no way to escape it that I can see, other
> > than by playing stupid games.
>
> A marginally better stupid game:
>
> #define IMMED(n) # ##n
> #define foo() mov r0, IMMED(5)
...in fact, a similar trick has been used in the m68k system call stubs of
the NetBSD C library for some time now:
#ifdef __STDC__
#define IMMEDIATE #
#define SYSTRAP(x) movl IMMEDIATE SYS_ ## x ## ,%d0; trap IMMEDIATE 0
#else
#define SYSTRAP(x) movl #SYS_/**/x,%d0; trap #0
#endif
--
-- Jason R. Thorpe <thorpej@zembu.com>