[dpdk-dev] [PATCH 1/3] app/testpmd: fix minor signed overflow in a constant

[Julien Cretin <julien.cretin@trust-in-soft.com>]

The expression (192 << 24) has an undefined behavior since:
- the integer constant 192 has type int, and
- 192 x 2^24 is not representable as an int.

Suffixing 192 with U defines a behavior since:
- the integer constant 192U has type unsigned int, and
- the value of (192U << 24) is defined as
  (192 x 2^24) % (UINT_MAX + 1)

This minor bug was found using TrustInSoft Analyzer.

Signed-off-by: Julien Cretin <julien.cretin@trust-in-soft.com>
---
 app/test-pmd/txonly.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/app/test-pmd/txonly.c b/app/test-pmd/txonly.c
index 1cf2574..5bbd34f 100644
--- a/app/test-pmd/txonly.c
+++ b/app/test-pmd/txonly.c
@@ -76,8 +76,8 @@
 #define UDP_SRC_PORT 1024
 #define UDP_DST_PORT 1024
 
-#define IP_SRC_ADDR ((192 << 24) | (168 << 16) | (0 << 8) | 1)
-#define IP_DST_ADDR ((192 << 24) | (168 << 16) | (0 << 8) | 2)
+#define IP_SRC_ADDR ((192U << 24) | (168 << 16) | (0 << 8) | 1)
+#define IP_DST_ADDR ((192U << 24) | (168 << 16) | (0 << 8) | 2)
 
 #define IP_DEFTTL  64   /* from RFC 1340. */
 #define IP_VERSION 0x40
-- 
1.9.1