[dpdk-dev] [PATCH] fix rte_memcpy() macro: avoid unused value warning

[Michal Jastrzebski <michalx.k.jastrzebski@intel.com>]

From: Pawel Wodkowski <pawelx.wodkowski@intel.com>

This change use statements in expressions C extension provided by gcc to avoid
'value computed is not used' warning/error when size is not known at compile
time.

Comments on possible side effects are welcome an tests are welcome.

Reported-by: Qiu, Michael <michael.qiu@intel.com>
Signed-off-by: Pawel Wodkowski <pawelx.wodkowski@intel.com>
---
 .../common/include/arch/x86/rte_memcpy.h           |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/librte_eal/common/include/arch/x86/rte_memcpy.h b/lib/librte_eal/common/include/arch/x86/rte_memcpy.h
index 290c5cd..c3e8b81 100644
--- a/lib/librte_eal/common/include/arch/x86/rte_memcpy.h
+++ b/lib/librte_eal/common/include/arch/x86/rte_memcpy.h
@@ -169,9 +169,9 @@ rte_mov256(uint8_t *dst, const uint8_t *src)
 }
 
 #define rte_memcpy(dst, src, n)              \
-	((__builtin_constant_p(n)) ?          \
+	({ (__builtin_constant_p(n)) ?          \
 	memcpy((dst), (src), (n)) :          \
-	rte_memcpy_func((dst), (src), (n)))
+	rte_memcpy_func((dst), (src), (n)); })
 
 static inline void *
 rte_memcpy_func(void *dst, const void *src, size_t n)
-- 
1.7.9.5