On Fri, 12 Apr 2024 13:13:16 +0200 Sebastian Brzezinka <[email protected]> wrote:
> From: Alexey Marchuk <[email protected]> > > 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 <[email protected]> > Signed-off-by: Sebastian Brzezinka <[email protected]> > --- > 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] + '>' NAK This adds more complexity to already overly complex meson build for mlx5.
