mk: disable warning for packed member pointer

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>
Tested-by: David Marchand <david.marchand@redhat.com>

diff --git a/mk/toolchain/gcc/rte.vars.mk b/mk/toolchain/gcc/rte.vars.mk
index d8b99fa..b852fcf 100644 (file)
--- 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