On Sat, 11 Nov 2023 08:56:34 -0800 Stephen Hemminger <step...@networkplumber.org> wrote:
> While examining the use of VLA in DPDK, ran into a bug in sfc driver. > > If DPDK is built with -Wvla, then the RTE_BUILD_BUG_ON() macro won't work > as written. Experimenting with a better more portable version of that macro > as: > #define RTE_BUILD_BUG_ON(e) _Static_assert(!(e), #e) Sending this as RFC also catches another driver with hidden failure. from ../drivers/event/opdl/opdl_ring.c:10: ./drivers/event/opdl/opdl_ring.c: In function ‘opdl_ring_create’: ./lib/eal/include/rte_common.h:498:44: error: expression in static assertion is not constant #define RTE_BUILD_BUG_ON(e) _Static_assert(!(e), #e) ^~~~ ./drivers/event/opdl/opdl_ring.c:913:2: note: in expansion of macro ‘RTE_BUILD_BUG_ON’ RTE_BUILD_BUG_ON(!rte_is_power_of_2(OPDL_DISCLAIMS_PER_LCORE));
