From: Alexey Marchuk <alexey...@mellanox.com> mlx5 common library checks if several symbols/definitions are presented in system header files. If some are not presented, they will be enabled by mlx5_glue library. The problem appears with clang and '-Werror' - code generated by meson is not compiled due to unused variable:
Code: #include <infiniband/mlx5dv.h> int main(void) { /* If it's not defined as a macro, try to use as a symbol */ #ifndef mlx5dv_create_flow_action_packet_reformat mlx5dv_create_flow_action_packet_reformat; #endif return 0; } Compiler stdout: Compiler stderr: /hpc/local/work/alexeymar/repo/spdk/dpdk/build-tmp/meson-private/tmp5obnak86/testfile.c:6:17: error: expression result unused [-Werror,-Wunused-value] mlx5dv_create_flow_action_packet_reformat; ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ As result, almost all symbols are enabled in mlx5_glue while they exist is system headers. As result, we get multiple symbols redefenitions when we compile mlx5_common. As a solution for this problem we can suppress -Wunused-vaurable using pragma DPDK 23.11 note: Starting with commit below, all cflags are passed to the has_header_symbol(). (33d6694) build: use C11 standard To make sure that the symbol is properly detected, the pedantic flags needs to be removed. Signed-off-by: Alexey Marchuk <alexey...@mellanox.com> Signed-off-by: Sebastian Brzezinka <sebastian.brzezi...@intel.com> --- drivers/common/mlx5/linux/meson.build | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/common/mlx5/linux/meson.build b/drivers/common/mlx5/linux/meson.build index cdee40c553..f3b8e5741b 100644 --- a/drivers/common/mlx5/linux/meson.build +++ b/drivers/common/mlx5/linux/meson.build @@ -209,7 +209,11 @@ if libmtcr_ul_found endif foreach arg:has_sym_args - mlx5_config.set(arg[0], cc.has_header_symbol(arg[1], arg[2], dependencies: libs, args: cflags)) + file_prefix = '#pragma clang diagnostic ignored "-Wunused-value"' + cflags += [ + '-Wno-pedantic', + ] + mlx5_config.set(arg[0], cc.has_header_symbol(arg[1], arg[2], prefix : file_prefix, dependencies: libs, args: cflags)) endforeach foreach arg:has_member_args file_prefix = '#include <' + arg[1] + '>' -- 2.34.1