http://bugs.winehq.org/show_bug.cgi?id=25945
Alexander Scott-Johns alexander.scott.johns+winebug@googlemail.com changed:
What |Removed |Added ---------------------------------------------------------------------------- Keywords| |download, source CC| |julliard@codeweavers.com
--- Comment #1 from Alexander Scott-Johns alexander.scott.johns+winebug@googlemail.com 2011-01-31 19:07:50 CST --- We could try something like (based on linux/kernel.h's BUILD_BUG_*):
#define C_ASSERT(e) (sizeof(struct { signed __static_assert : (e)?1:-1; }))
This will evaluate to sizeof(int), and can be used in constant expressions. I'm not sure if this version of C_ASSERT can be made into a declaration, as using it inside a function prototype makes GCC complain: "anonymous struct declared inside parameter list".
If C99 features are available, this should work (it uses array literals and array designators):
#define C_ASSERT(e) \ extern void __C_ASSERT__(int [sizeof((char[]){ [-!(e)] = 0 })])
The _Static_assert(e,m) thing from C1x is implemented in GCC 4.6. If it's available, we should use it, instead of using a homebrew solution (which can then be a hacky, not-accepted-by-modern-GCC thing).
#ifdef _Static_assert /* There is a way to check for this, right? */ # define C_ASSERT(e) _Static_assert((e), #e " was false") #elsif defined(_MSC_VER) # define C_ASSERT(e) typedef char __C_ASSERT__[(e)?1:-1] #elsif __STDC_VERSION__ >= 199901L # define C_ASSERT(e) \ extern void __C_ASSERT__(int [sizeof((char[]){ [-!(e)] = 0 })]) #else /* C99 not supported: no VLAs */ # define C_ASSERT(e) extern void __C_ASSERT__(int [(e)?1:-1]) #endif