On 5/4/2020 10:03 PM, David Christensen wrote:
> 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 <d...@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"
I can't find "rte_altivec.h", am I missing something.
With just ignoring "-Warray-bounds" changes, I confirm ena build issue is fixed
with gcc 9.1
>
> #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
>
