diff options
Diffstat (limited to 'include/qemu/osdep.h')
| -rw-r--r-- | include/qemu/osdep.h | 27 |
1 files changed, 20 insertions, 7 deletions
diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h index e4a4eb2d61..18b940db75 100644 --- a/include/qemu/osdep.h +++ b/include/qemu/osdep.h @@ -383,19 +383,28 @@ void QEMU_ERROR("code path is reachable") * determined by the pre-processor instead of the compiler, you'll * have to open-code it. Sadly, Coverity is severely confused by the * constant variants, so we have to dumb things down there. + * + * Preprocessor sorcery ahead: use different identifiers for the local + * variables in each expansion, so we can nest macro calls without + * shadowing variables. */ -#undef MIN -#define MIN(a, b) \ +#define MIN_INTERNAL(a, b, _a, _b) \ ({ \ typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ _a < _b ? _a : _b; \ }) -#undef MAX -#define MAX(a, b) \ +#undef MIN +#define MIN(a, b) \ + MIN_INTERNAL((a), (b), MAKE_IDENTFIER(_a), MAKE_IDENTFIER(_b)) + +#define MAX_INTERNAL(a, b, _a, _b) \ ({ \ typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ _a > _b ? _a : _b; \ }) +#undef MAX +#define MAX(a, b) \ + MAX_INTERNAL((a), (b), MAKE_IDENTFIER(_a), MAKE_IDENTFIER(_b)) #ifdef __COVERITY__ # define MIN_CONST(a, b) ((a) < (b) ? (a) : (b)) @@ -416,14 +425,18 @@ void QEMU_ERROR("code path is reachable") /* * Minimum function that returns zero only if both values are zero. * Intended for use with unsigned values only. + * + * Preprocessor sorcery ahead: use different identifiers for the local + * variables in each expansion, so we can nest macro calls without + * shadowing variables. */ -#ifndef MIN_NON_ZERO -#define MIN_NON_ZERO(a, b) \ +#define MIN_NON_ZERO_INTERNAL(a, b, _a, _b) \ ({ \ typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ _a == 0 ? _b : (_b == 0 || _b > _a) ? _a : _b; \ }) -#endif +#define MIN_NON_ZERO(a, b) \ + MIN_NON_ZERO_INTERNAL((a), (b), MAKE_IDENTFIER(_a), MAKE_IDENTFIER(_b)) /* * Round number down to multiple. Safe when m is not a power of 2 (see |