On Thu, 4 May 2017 16:38:13 +0100 Bruce Richardson <bruce.richard...@intel.com> wrote:
> There are two new warnings in GCC 7 that cause problems in the DPDK > compile. > > 1. GCC now warns if you have a switch fall-through without a suitable > comment indicating that it was intentional. The compiler supports a number > of levels of warning which are triggered depending on the type of message > used, with level 3 being the default. To accept a wider range of possible > fall-through messages, we adjust this down to level 2. > > 2. GCC also warns about an snprintf where there may be truncation and the > return value is not checked. Given that we often use snprintf in DPDK in > place of strncpy, and in many cases where truncation is not a problem, we > can just disable this particular warning. > > Signed-off-by: Bruce Richardson <bruce.richard...@intel.com> > --- > mk/toolchain/gcc/rte.vars.mk | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/mk/toolchain/gcc/rte.vars.mk b/mk/toolchain/gcc/rte.vars.mk > index 5caa600..3834e00 100644 > --- a/mk/toolchain/gcc/rte.vars.mk > +++ b/mk/toolchain/gcc/rte.vars.mk > @@ -99,5 +99,12 @@ ifeq ($(shell test $(GCC_VERSION) -lt 47 && echo 1), 1) > WERROR_FLAGS += -Wno-uninitialized > endif > > +ifeq ($(shell test $(GCC_VERSION) -gt 70 && echo 1), 1) > +# Tell GCC only to error for switch fallthroughs without a suitable comment > +WERROR_FLAGS += -Wimplicit-fallthrough=2 > +# Ignore errors for snprintf truncation > +WERROR_FLAGS += -Wno-format-truncation > +endif > + > export CC AS AR LD OBJCOPY OBJDUMP STRIP READELF > export TOOLCHAIN_CFLAGS TOOLCHAIN_LDFLAGS TOOLCHAIN_ASFLAGS Please fix the code not neuter warnings
