[dpdk-dev] [PATCH v2] eal: fix rte_memcpy build on ppc with gcc 9.3

[David Christensen]

Building DPDK on Ubuntu 20.04 with GCC 9.3.0 results in a "subscript is
outside array bounds" message in rte_memcpy function.  The build error
is caused by an interaction between __builtin_constant_p and
"-Werror=array-bounds" as described in this bugzilla:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90387

Modify the code to disable the array-bounds check for GCC versions 9.0
to 9.3.

Signed-off-by: David Christensen <drc at linux.vnet.ibm.com>
---

v2:
* Replace __GNUC__ and __GNUC_MINOR__ with GCC_VERSION
---
 lib/librte_eal/ppc/include/rte_memcpy.h | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/lib/librte_eal/ppc/include/rte_memcpy.h b/lib/librte_eal/ppc/include/rte_memcpy.h
index 25311ba1d..de47a5d2e 100644
--- a/lib/librte_eal/ppc/include/rte_memcpy.h
+++ b/lib/librte_eal/ppc/include/rte_memcpy.h
@@ -8,8 +8,8 @@
 
 #include <stdint.h>
 #include <string.h>
-/*To include altivec.h, GCC version must  >= 4.8 */
-#include <altivec.h>
+#include "rte_altivec.h"
+#include "rte_common.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -17,6 +17,11 @@ extern "C" {
 
 #include "generic/rte_memcpy.h"
 
+#if (GCC_VERSION >= 90000 && GCC_VERSION < 90400)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Warray-bounds"
+#endif
+
 static inline void
 rte_mov16(uint8_t *dst, const uint8_t *src)
 {
@@ -192,6 +197,10 @@ rte_memcpy_func(void *dst, const void *src, size_t n)
 	return ret;
 }
 
+#if (GCC_VERSION >= 90000 && GCC_VERSION < 90400)
+#pragma GCC diagnostic pop
+#endif
+
 #ifdef __cplusplus
 }
 #endif
-- 
2.18.1