Re: [PATCH 01/12] kbuild: make -Woverride-init warnings more consistent

[Hamza Mahfooz <hamza.mahfooz@amd.com>]

Cc: amd-gfx@lists.freedesktop.org

On 3/26/24 10:47, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> The -Woverride-init warn about code that may be intentional or not,
> but the inintentional ones tend to be real bugs, so there is a bit of
> disagreement on whether this warning option should be enabled by default
> and we have multiple settings in scripts/Makefile.extrawarn as well as
> individual subsystems.
> 
> Older versions of clang only supported -Wno-initializer-overrides with
> the same meaning as gcc's -Woverride-init, though all supported versions
> now work with both. Because of this difference, an earlier cleanup of
> mine accidentally turned the clang warning off for W=1 builds and only
> left it on for W=2, while it's still enabled for gcc with W=1.
> 
> There is also one driver that only turns the warning off for newer
> versions of gcc but not other compilers, and some but not all the
> Makefiles still use a cc-disable-warning conditional that is no
> longer needed with supported compilers here.
> 
> Address all of the above by removing the special cases for clang
> and always turning the warning off unconditionally where it got
> in the way, using the syntax that is supported by both compilers.
> 
> Fixes: 2cd3271b7a31 ("kbuild: avoid duplicate warning options")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>

For the amdgpu changes.

> ---
>   drivers/gpu/drm/amd/display/dc/dce110/Makefile |  2 +-
>   drivers/gpu/drm/amd/display/dc/dce112/Makefile |  2 +-
>   drivers/gpu/drm/amd/display/dc/dce120/Makefile |  2 +-
>   drivers/gpu/drm/amd/display/dc/dce60/Makefile  |  2 +-
>   drivers/gpu/drm/amd/display/dc/dce80/Makefile  |  2 +-
>   drivers/gpu/drm/i915/Makefile                  |  6 +++---
>   drivers/gpu/drm/xe/Makefile                    |  4 ++--
>   drivers/net/ethernet/renesas/sh_eth.c          |  2 +-
>   drivers/pinctrl/aspeed/Makefile                |  2 +-
>   fs/proc/Makefile                               |  2 +-
>   kernel/bpf/Makefile                            |  2 +-
>   mm/Makefile                                    |  3 +--
>   scripts/Makefile.extrawarn                     | 10 +++-------
>   13 files changed, 18 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/dce110/Makefile b/drivers/gpu/drm/amd/display/dc/dce110/Makefile
> index f0777d61c2cb..c307f040e48f 100644
> --- a/drivers/gpu/drm/amd/display/dc/dce110/Makefile
> +++ b/drivers/gpu/drm/amd/display/dc/dce110/Makefile
> @@ -23,7 +23,7 @@
>   # Makefile for the 'controller' sub-component of DAL.
>   # It provides the control and status of HW CRTC block.
>   
> -CFLAGS_$(AMDDALPATH)/dc/dce110/dce110_resource.o = $(call cc-disable-warning, override-init)
> +CFLAGS_$(AMDDALPATH)/dc/dce110/dce110_resource.o = -Wno-override-init
>   
>   DCE110 = dce110_timing_generator.o \
>   dce110_compressor.o dce110_opp_regamma_v.o \
> diff --git a/drivers/gpu/drm/amd/display/dc/dce112/Makefile b/drivers/gpu/drm/amd/display/dc/dce112/Makefile
> index 7e92effec894..683866797709 100644
> --- a/drivers/gpu/drm/amd/display/dc/dce112/Makefile
> +++ b/drivers/gpu/drm/amd/display/dc/dce112/Makefile
> @@ -23,7 +23,7 @@
>   # Makefile for the 'controller' sub-component of DAL.
>   # It provides the control and status of HW CRTC block.
>   
> -CFLAGS_$(AMDDALPATH)/dc/dce112/dce112_resource.o = $(call cc-disable-warning, override-init)
> +CFLAGS_$(AMDDALPATH)/dc/dce112/dce112_resource.o = -Wno-override-init
>   
>   DCE112 = dce112_compressor.o
>   
> diff --git a/drivers/gpu/drm/amd/display/dc/dce120/Makefile b/drivers/gpu/drm/amd/display/dc/dce120/Makefile
> index 1e3ef68a452a..8f508e662748 100644
> --- a/drivers/gpu/drm/amd/display/dc/dce120/Makefile
> +++ b/drivers/gpu/drm/amd/display/dc/dce120/Makefile
> @@ -24,7 +24,7 @@
>   # It provides the control and status of HW CRTC block.
>   
>   
> -CFLAGS_$(AMDDALPATH)/dc/dce120/dce120_resource.o = $(call cc-disable-warning, override-init)
> +CFLAGS_$(AMDDALPATH)/dc/dce120/dce120_resource.o = -Wno-override-init
>   
>   DCE120 = dce120_timing_generator.o
>   
> diff --git a/drivers/gpu/drm/amd/display/dc/dce60/Makefile b/drivers/gpu/drm/amd/display/dc/dce60/Makefile
> index fee331accc0e..eede83ad91fa 100644
> --- a/drivers/gpu/drm/amd/display/dc/dce60/Makefile
> +++ b/drivers/gpu/drm/amd/display/dc/dce60/Makefile
> @@ -23,7 +23,7 @@
>   # Makefile for the 'controller' sub-component of DAL.
>   # It provides the control and status of HW CRTC block.
>   
> -CFLAGS_$(AMDDALPATH)/dc/dce60/dce60_resource.o = $(call cc-disable-warning, override-init)
> +CFLAGS_$(AMDDALPATH)/dc/dce60/dce60_resource.o = -Wno-override-init
>   
>   DCE60 = dce60_timing_generator.o dce60_hw_sequencer.o \
>   	dce60_resource.o
> diff --git a/drivers/gpu/drm/amd/display/dc/dce80/Makefile b/drivers/gpu/drm/amd/display/dc/dce80/Makefile
> index 7eefffbdc925..fba189d26652 100644
> --- a/drivers/gpu/drm/amd/display/dc/dce80/Makefile
> +++ b/drivers/gpu/drm/amd/display/dc/dce80/Makefile
> @@ -23,7 +23,7 @@
>   # Makefile for the 'controller' sub-component of DAL.
>   # It provides the control and status of HW CRTC block.
>   
> -CFLAGS_$(AMDDALPATH)/dc/dce80/dce80_resource.o = $(call cc-disable-warning, override-init)
> +CFLAGS_$(AMDDALPATH)/dc/dce80/dce80_resource.o = -Wno-override-init
>   
>   DCE80 = dce80_timing_generator.o
>   
> diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
> index 3ef6ed41e62b..4c2f85632391 100644
> --- a/drivers/gpu/drm/i915/Makefile
> +++ b/drivers/gpu/drm/i915/Makefile
> @@ -33,9 +33,9 @@ endif
>   subdir-ccflags-$(CONFIG_DRM_I915_WERROR) += -Werror
>   
>   # Fine grained warnings disable
> -CFLAGS_i915_pci.o = $(call cc-disable-warning, override-init)
> -CFLAGS_display/intel_display_device.o = $(call cc-disable-warning, override-init)
> -CFLAGS_display/intel_fbdev.o = $(call cc-disable-warning, override-init)
> +CFLAGS_i915_pci.o = -Wno-override-init
> +CFLAGS_display/intel_display_device.o = -Wno-override-init
> +CFLAGS_display/intel_fbdev.o = -Wno-override-init
>   
>   # Support compiling the display code separately for both i915 and xe
>   # drivers. Define I915 when building i915.
> diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
> index 5a428ca00f10..c29a850859ad 100644
> --- a/drivers/gpu/drm/xe/Makefile
> +++ b/drivers/gpu/drm/xe/Makefile
> @@ -172,8 +172,8 @@ subdir-ccflags-$(CONFIG_DRM_XE_DISPLAY) += \
>   	-Ddrm_i915_gem_object=xe_bo \
>   	-Ddrm_i915_private=xe_device
>   
> -CFLAGS_i915-display/intel_fbdev.o = $(call cc-disable-warning, override-init)
> -CFLAGS_i915-display/intel_display_device.o = $(call cc-disable-warning, override-init)
> +CFLAGS_i915-display/intel_fbdev.o = -Wno-override-init
> +CFLAGS_i915-display/intel_display_device.o = -Wno-override-init
>   
>   # Rule to build SOC code shared with i915
>   $(obj)/i915-soc/%.o: $(srctree)/drivers/gpu/drm/i915/soc/%.c FORCE
> diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
> index 475e1e8c1d35..0786eb0da391 100644
> --- a/drivers/net/ethernet/renesas/sh_eth.c
> +++ b/drivers/net/ethernet/renesas/sh_eth.c
> @@ -50,7 +50,7 @@
>    * the macros available to do this only define GCC 8.
>    */
>   __diag_push();
> -__diag_ignore(GCC, 8, "-Woverride-init",
> +__diag_ignore_all("-Woverride-init",
>   	      "logic to initialize all and then override some is OK");
>   static const u16 sh_eth_offset_gigabit[SH_ETH_MAX_REGISTER_OFFSET] = {
>   	SH_ETH_OFFSET_DEFAULTS,
> diff --git a/drivers/pinctrl/aspeed/Makefile b/drivers/pinctrl/aspeed/Makefile
> index 489ea1778353..db2a7600ae2b 100644
> --- a/drivers/pinctrl/aspeed/Makefile
> +++ b/drivers/pinctrl/aspeed/Makefile
> @@ -1,7 +1,7 @@
>   # SPDX-License-Identifier: GPL-2.0-only
>   # Aspeed pinctrl support
>   
> -ccflags-y += $(call cc-option,-Woverride-init)
> +ccflags-y += -Woverride-init
>   obj-$(CONFIG_PINCTRL_ASPEED)	+= pinctrl-aspeed.o pinmux-aspeed.o
>   obj-$(CONFIG_PINCTRL_ASPEED_G4)	+= pinctrl-aspeed-g4.o
>   obj-$(CONFIG_PINCTRL_ASPEED_G5)	+= pinctrl-aspeed-g5.o
> diff --git a/fs/proc/Makefile b/fs/proc/Makefile
> index bd08616ed8ba..7b4db9c56e6a 100644
> --- a/fs/proc/Makefile
> +++ b/fs/proc/Makefile
> @@ -5,7 +5,7 @@
>   
>   obj-y   += proc.o
>   
> -CFLAGS_task_mmu.o	+= $(call cc-option,-Wno-override-init,)
> +CFLAGS_task_mmu.o	+= -Wno-override-init
>   proc-y			:= nommu.o task_nommu.o
>   proc-$(CONFIG_MMU)	:= task_mmu.o
>   
> diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
> index 368c5d86b5b7..e497011261b8 100644
> --- a/kernel/bpf/Makefile
> +++ b/kernel/bpf/Makefile
> @@ -4,7 +4,7 @@ ifneq ($(CONFIG_BPF_JIT_ALWAYS_ON),y)
>   # ___bpf_prog_run() needs GCSE disabled on x86; see 3193c0836f203 for details
>   cflags-nogcse-$(CONFIG_X86)$(CONFIG_CC_IS_GCC) := -fno-gcse
>   endif
> -CFLAGS_core.o += $(call cc-disable-warning, override-init) $(cflags-nogcse-yy)
> +CFLAGS_core.o += -Wno-override-init $(cflags-nogcse-yy)
>   
>   obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o log.o token.o
>   obj-$(CONFIG_BPF_SYSCALL) += bpf_iter.o map_iter.o task_iter.o prog_iter.o link_iter.o
> diff --git a/mm/Makefile b/mm/Makefile
> index e4b5b75aaec9..4abb40b911ec 100644
> --- a/mm/Makefile
> +++ b/mm/Makefile
> @@ -29,8 +29,7 @@ KCOV_INSTRUMENT_mmzone.o := n
>   KCOV_INSTRUMENT_vmstat.o := n
>   KCOV_INSTRUMENT_failslab.o := n
>   
> -CFLAGS_init-mm.o += $(call cc-disable-warning, override-init)
> -CFLAGS_init-mm.o += $(call cc-disable-warning, initializer-overrides)
> +CFLAGS_init-mm.o += -Wno-override-init
>   
>   mmu-y			:= nommu.o
>   mmu-$(CONFIG_MMU)	:= highmem.o memory.o mincore.o \
> diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
> index 3ce5d503a6da..c5af566e911a 100644
> --- a/scripts/Makefile.extrawarn
> +++ b/scripts/Makefile.extrawarn
> @@ -114,6 +114,8 @@ KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
>   KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
>   KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
>   
> +KBUILD_CFLAGS += -Wno-override-init # alias for -Wno-initializer-overrides in clang
> +
>   ifdef CONFIG_CC_IS_CLANG
>   # Clang before clang-16 would warn on default argument promotions.
>   ifneq ($(call clang-min-version, 160000),y)
> @@ -151,10 +153,6 @@ KBUILD_CFLAGS += -Wtype-limits
>   KBUILD_CFLAGS += $(call cc-option, -Wmaybe-uninitialized)
>   KBUILD_CFLAGS += $(call cc-option, -Wunused-macros)
>   
> -ifdef CONFIG_CC_IS_CLANG
> -KBUILD_CFLAGS += -Winitializer-overrides
> -endif
> -
>   KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN2
>   
>   else
> @@ -164,9 +162,7 @@ KBUILD_CFLAGS += -Wno-missing-field-initializers
>   KBUILD_CFLAGS += -Wno-type-limits
>   KBUILD_CFLAGS += -Wno-shift-negative-value
>   
> -ifdef CONFIG_CC_IS_CLANG
> -KBUILD_CFLAGS += -Wno-initializer-overrides
> -else
> +ifdef CONFIG_CC_IS_GCC
>   KBUILD_CFLAGS += -Wno-maybe-uninitialized
>   endif
>   
-- 
Hamza