X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fverify.h;h=a0849a8c4b4437fa24be0f9130932c9add8a2b76;hb=8a11db185bb84ee7d2be080ffc71214e14824767;hp=dbca35c817d3a6e3f1dedae491eb21f967d2f874;hpb=8465329af7e7da7e9e8c61a3c0f71d4cee89ccd5;p=gnulib.git diff --git a/lib/verify.h b/lib/verify.h index dbca35c81..a0849a8c4 100644 --- a/lib/verify.h +++ b/lib/verify.h @@ -69,9 +69,9 @@ if the entity names are not disambiguated. A workaround is to attach the current line number to the entity name: - #define GL_CONCAT0(x, y) x##y - #define GL_CONCAT(x, y) GL_CONCAT0 (x, y) - extern struct {...} * GL_CONCAT(dummy,__LINE__); + #define _GL_CONCAT0(x, y) x##y + #define _GL_CONCAT(x, y) _GL_CONCAT0 (x, y) + extern struct {...} * _GL_CONCAT(dummy,__LINE__); But this has the problem that two invocations of verify from within the same macro would collide, since the __LINE__ value @@ -123,19 +123,22 @@ Use a template type to work around the problem. */ /* Concatenate two preprocessor tokens. */ -# define GL_CONCAT(x, y) GL_CONCAT0 (x, y) -# define GL_CONCAT0(x, y) x##y - -/* __COUNTER__ evaluates to 0, 1, 2,..., adding one one each time the - preprocessor uses it. If the preprocessor doesn't support this - builtin macro, define it to 0. */ -# ifndef __COUNTER__ -# define __COUNTER__ 0 +# define _GL_CONCAT(x, y) _GL_CONCAT0 (x, y) +# define _GL_CONCAT0(x, y) x##y + +/* _GL_COUNTER is an integer, preferably one that changes each time we + use it. Use __COUNTER__ if it works, falling back on __LINE__ + otherwise. __LINE__ isn't perfect, but it's better than a + constant. */ +# if defined __COUNTER__ && __COUNTER__ != __COUNTER__ +# define _GL_COUNTER __COUNTER__ +# else +# define _GL_COUNTER __LINE__ # endif /* Generate a symbol with the given prefix, making it unique if possible. */ -# define GL_GENSYM(prefix) GL_CONCAT(prefix, __COUNTER__) +# define _GL_GENSYM(prefix) _GL_CONCAT(prefix, _GL_COUNTER) /* Verify requirement R at compile-time, as an integer constant expression. Return 1. */ @@ -155,6 +158,6 @@ template trailing ';'. */ # define verify(R) \ - extern int (* GL_GENSYM(verify_function) (void)) [verify_true (R)] + extern int (* _GL_GENSYM(verify_function) (void)) [verify_true (R)] #endif