In file included from pulse/timeval.c:32:0:
pulse/timeval.c: In function 'pa_timeval_add':
./pulsecore/macro.h:303:28: warning: left shift of negative value [-Wshift-negative-value]
? ~(~(type) 0 << (8*sizeof(type)-1))
reported by Ubuntu gcc-6
gcc-6 adds -Wshift-negative-value (enabled by -Wextra) which warns
about left shifting a negative value. Such shifts are undefined
because they depend on the representation of negative values.
also works with -Wshift-overflow=2
Signed-off-by: Peter Meerwald <pmeerw at pmeerw.net>
---
src/pulsecore/macro.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/src/pulsecore/macro.h b/src/pulsecore/macro.h
index 1716f81..1e15f4f 100644
--- a/src/pulsecore/macro.h
+++ b/src/pulsecore/macro.h
@@ -298,14 +298,16 @@ static inline size_t PA_PAGE_ALIGN(size_t l) {
#define PA_INT_TYPE_SIGNED(type) (!!((type) 0 > (type) -1))
+#define PA_INT_TYPE_HALF(type) ((type) 1 << (sizeof(type)*8 - 2))
+
#define PA_INT_TYPE_MAX(type) \
((type) (PA_INT_TYPE_SIGNED(type) \
- ? ~(~(type) 0 << (8*sizeof(type)-1)) \
+ ? (PA_INT_TYPE_HALF(type) - 1 + PA_INT_TYPE_HALF(type)) \
: (type) -1))
#define PA_INT_TYPE_MIN(type) \
((type) (PA_INT_TYPE_SIGNED(type) \
- ? (~(type) 0 << (8*sizeof(type)-1)) \
+ ? (-1 - PA_INT_TYPE_MAX(type)) \
: (type) 0))
/* We include this at the very last place */
--
2.7.0
