On Tue, 24 Oct 2017, Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> wrote: > Recently W=1 on gcc-7.2 (-Wunused-const-variable) caught a regression > that had been lurking for 6 months, so lets try enabling the full set of > warnings for CI builds. This means more patches will be rejected early > that contain trivial and sometimes not so trivial bugs. However, our > code does not yet compile cleanly with W=1, so we have to apply a filter > to the set of warnings until we can eliminate the mistakes. It also > means that developers will have to be running the full gamut of gcc to > ensure that as warnings come and go with gcc updates, we have the CI > build prepared. > > v2: Use fine-grained -Wno overrides. Inside the makefile, we can > specify CFLAGS on a per-object level, which allows us to limit the scope > of any particular warning override. > v3: Place per-file overrides after the main enabling block. > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> > Cc: Jani Nikula <jani.nikula@xxxxxxxxx> > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> > Cc: Tomi Sarvela <tomi.p.sarvela@xxxxxxxxx> > Cc: Michal Wajdeczko <michal.wajdeczko@xxxxxxxxx> > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Acked-by: Tomi Sarvela <tomi.p.sarvela@xxxxxxxxx> > Reviewed-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> > --- > Seeking more acks for making our lives harder by giving gcc free reign > in its warnings. Acked-by: Jani Nikula <jani.nikula@xxxxxxxxx> > -Chris > --- > drivers/gpu/drm/i915/Makefile | 21 ++++++++++++++++++++- > 1 file changed, 20 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile > index 6c3b0481ef82..7750be8e27a6 100644 > --- a/drivers/gpu/drm/i915/Makefile > +++ b/drivers/gpu/drm/i915/Makefile > @@ -2,7 +2,26 @@ > # Makefile for the drm device driver. This driver provides support for the > # Direct Rendering Infrastructure (DRI) in XFree86 4.1.0 and higher. > > -subdir-ccflags-$(CONFIG_DRM_I915_WERROR) := -Werror > +# Add a set of useful warning flags and enable -Werror for CI to prevent > +# trivial mistakes from creeping in. We have to do this piecemeal as we reject > +# any patch that isn't warning clean, so turning on -Wall -Wextra (or W=1) we > +# need to filter out dubious warnings. Still it is our interest > +# to keep running locally with W=1 C=1 until we are completely clean. > +# > +# Note the danger in using -Wall -Wextra is that when CI updates gcc we > +# will most likely get a sudden build breakage... Hopefully we will fix > +# new warnings before CI updates! > +subdir-ccflags-y := -Wall -Wextra > +subdir-ccflags-y += $(call cc-option,-Wno-unused-parameter,) > +subdir-ccflags-y += $(call cc-option,-Wno-type-limits,) > +subdir-ccflags-y += $(call cc-option,-Wno-missing-field-initializers,) > +subdir-ccflags-y += $(call cc-option,-Wno-implicit-fallthrough,) > +subdir-ccflags-$(CONFIG_DRM_I915_WERROR) += -Werror > + > +# Fine grained warnings disable > +CFLAGS_i915_pci.o = $(call cc-option,-Wno-override-init,) > +CFLAGS_intel_fbdev.o = $(call cc-option,-Wno-override-init,) > + > subdir-ccflags-y += \ > $(call as-instr,movntdqa (%eax)$(comma)%xmm0,-DCONFIG_AS_MOVNTDQA) -- Jani Nikula, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
