Re: [dpdk-dev] [PATCH] mk: disable warning with gcc 9 on Fedora 30

[David Marchand <david.marchand@redhat.com>]

On Thu, May 2, 2019 at 11:33 AM Reshma Pattan <reshma.pattan@intel.com>
wrote:

> gcc 9 on Fedora 30 gives an error
> "taking address of packed member may result in an
> unaligned pointer value" warnings.
>
> For clang builds this warning is already disabled,
> so disable "-Waddress-of-packed-member" for gcc builds
> also.
>
> Snippet of build error:
> ...lib/librte_eal/linux/eal/eal_memalloc.c: In function ‘alloc_seg_walk’:
> ...lib/librte_eal/linux/eal/eal_memalloc.c:768:12: error: taking address
> of packed member of ‘struct rte_mem_config’ may result in an unaligned
> pointer value [-Werror=address-of-packed-member]
>   768 |  cur_msl = &mcfg->memsegs[msl_idx];
>       |            ^~~~~~~~~~~~~~~~~~~~~~~
>
> Signed-off-by: Reshma Pattan <reshma.pattan@intel.com>
> ---
>  mk/toolchain/gcc/rte.vars.mk | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/mk/toolchain/gcc/rte.vars.mk b/mk/toolchain/gcc/rte.vars.mk
> index d8b99faf6..b852fcfd7 100644
> --- a/mk/toolchain/gcc/rte.vars.mk
> +++ b/mk/toolchain/gcc/rte.vars.mk
> @@ -87,5 +87,8 @@ WERROR_FLAGS += -Wimplicit-fallthrough=2
>  WERROR_FLAGS += -Wno-format-truncation
>  endif
>
> +# disable packed member unalign warnings
> +WERROR_FLAGS += -Wno-address-of-packed-member
> +
>  export CC AS AR LD OBJCOPY OBJDUMP STRIP READELF
>  export TOOLCHAIN_CFLAGS TOOLCHAIN_LDFLAGS TOOLCHAIN_ASFLAGS
> --
> 2.21.0
>
>
Tested on rhel-7 and fedora-30.
Tested-by: David Marchand <david.marchand@redhat.com>


-- 
David Marchand