Re: [Tinycc-devel] macro expansion bug

[Vincent Lefevre]

On 2014-04-02 14:46:36 +0100, Jay Foad wrote:
> With tcc I get:
> 
> $ cat cat.c
> #define CAT2(a,b) a##b
> #define CAT(a,b) CAT2(a,b)
> #define AB(x) CAT(x,y)
> CAT(A,B)(x)
> $ ./tcc -E cat.c
> # 2 "cat.c"
> 
> 
> CAT(x,y)
> 
> But I think this is wrong, because gcc -E and clang -E both expand the
> last line further to give just:
> 
> xy

For future testcases, this means that this wouldn't be equivalent to:

#define CAT2(a,b) a##b(x)
#define CAT(a,b) CAT2(a,b)
#define AB(x) CAT(x,y)
CAT(A,B)

and

#define CAT2(a,b) a##b
#define CAT(a,b) CAT2(a,b)(x)
#define AB(x) CAT(x,y)
CAT(A,B)

which both give:

CAT(x,y)

for the last line.

FYI, icc (ICC) 13.1.0 20130121 behaves like gcc.

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