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#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
 
int main()
{
    BUILD_BUG_ON_ZERO(1);
    return 0;
}

prog.c: In function ‘main’:
prog.c:1:45: error: negative width in bit-field ‘<anonymous>’
 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
                                             ^
prog.c:6:5: note: in expansion of macro ‘BUILD_BUG_ON_ZERO’
     BUILD_BUG_ON_ZERO(1);
     ^
prog.c:1:30: warning: statement with no effect [-Wunused-value]
 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
                              ^
prog.c:6:5: note: in expansion of macro ‘BUILD_BUG_ON_ZERO’
     BUILD_BUG_ON_ZERO(1);
     ^

Standard output is empty