[cfe-dev] cpp difference between gcc and clang?

[Joel Sherrill]

Hi,

RTEMS uses preprocessed assembly files (.S).
I have a small test case which compiles
with i386 gcc and not with clang from the svn
head.

========================
#define __USER_LABEL_PREFIX__
#define EXPAND0(x) x
#define CONCAT0(a,b) EXPAND0(a)EXPAND0(b)

#define SYM(x) CONCAT0 (__USER_LABEL_PREFIX__, x)

         .text

.set RUNCONTEXT_ARG,   4                   /* save context argument */
.set HEIRCONTEXT_ARG,  8                   /* restore context argument */

SYM(_label):
     nop
========================

$ clang -c set_asm.S
/tmp/cc-Y6Q2YB.s:14:24: error: unexpected token in assignment
.set HEIRCONTEXT_ARG, 8_label:

This is a cut down and if I simplify it much more,
it works.

-- 
Joel Sherrill, Ph.D.             Director of Research&  Development
joel.sherrill at OARcorp.com        On-Line Applications Research
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