| Message ID | 20190515043753.9853-1-yamada.masahiro@socionext.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/i915: drop unneeded -Wall addition | expand |
Quoting Masahiro Yamada (2019-05-15 05:37:53) > The top level Makefile adds -Wall globally: > > KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \ > > I see two "-Wall" added for compiling under drivers/gpu/drm/i915/. Does it matter? Is the statement in i915/Makefile not more complete for saying "-Wall -Wextra -Werror"? > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > --- > > BTW, I have a question in the comment: > > "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!" > > Enabling whatever warning options does not cause build breakage. > -Werror does. > > So, I think the correct statement is: > > "Note the danger in using -Werror is that when CI updates gcc we ... No. CI enforces -Werror and that is constant, so the uncontrolled variable, the danger, lies in using the unreliable heuristics gcc may arbitrary enable between versions. That the set of warnings causing an error may be different between CI and the developer. -Chris
On Wed, May 15, 2019 at 3:25 PM Chris Wilson <chris@chris-wilson.co.uk> wrote: > > Quoting Masahiro Yamada (2019-05-15 05:37:53) > > The top level Makefile adds -Wall globally: > > > > KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \ > > > > I see two "-Wall" added for compiling under drivers/gpu/drm/i915/. > > Does it matter? Is the statement in i915/Makefile not more complete for > saying "-Wall -Wextra -Werror"? Not fatal, but better to fix. Why not fix the comment if you mind "-Wall" in the comment? It will be easy to rephrase the comments without explicitly mentioning -Wall or -Wextra. I reworded it more concisely: # We aggressively eliminate warnings, # so here are more warning options than default. That's it. The CI is your local matter. Distracting comments should not be added in the upstream code in the first place. > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > > --- > > > > BTW, I have a question in the comment: > > > > "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!" > > > > Enabling whatever warning options does not cause build breakage. > > -Werror does. > > > > So, I think the correct statement is: > > > > "Note the danger in using -Werror is that when CI updates gcc we ... > > No. Heh, I thought the answer was Yes, since I saw the following in this Makefile. # Add a set of useful warning flags and enable -Werror for CI to prevent > CI enforces -Werror and that is constant, so the uncontrolled > variable, the danger, lies in using the unreliable heuristics gcc may > arbitrary enable between versions. That the set of warnings causing an > error may be different between CI and the developer. > -Chris
diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile index fbcb0904f4a8..4a4f60c7edfc 100644 --- a/drivers/gpu/drm/i915/Makefile +++ b/drivers/gpu/drm/i915/Makefile @@ -12,7 +12,7 @@ # 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 := -Wextra subdir-ccflags-y += $(call cc-disable-warning, unused-parameter) subdir-ccflags-y += $(call cc-disable-warning, type-limits) subdir-ccflags-y += $(call cc-disable-warning, missing-field-initializers)
The top level Makefile adds -Wall globally: KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \ I see two "-Wall" added for compiling under drivers/gpu/drm/i915/. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> --- BTW, I have a question in the comment: "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!" Enabling whatever warning options does not cause build breakage. -Werror does. So, I think the correct statement is: "Note the danger in using -Werror is that when CI updates gcc we ... ^^^^^^^ drivers/gpu/drm/i915/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)