arch/m68k/Makefile computes lots of unneeded cc-option calls. For example, if CONFIG_M5441x is not defined, there is not point in evaluating the following compiler flag. cpuflags-$(CONFIG_M5441x) := $(call cc-option,-mcpu=54455,-mcfv4e) The result is set to cpuflags-, then thrown away. The right hand side of ':=' is immediately expanded. Hence, all of the 16 calls for cc-option are evaluated. This is expensive since cc-option invokes the compiler. This occurs even if you are not attempting to build anything, like 'make ARCH=m68k help'. Use '=' to expand the value _lazily_. The evaluation for cc-option is delayed until $(cpuflags-y) is expanded. So, the cc-option test happens just once at most. This commit mimics tune-y of arch/arm/Makefile. Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> --- arch/m68k/Makefile | 45 ++++++++++++++++++++++++--------------------- 1 file changed, 24 insertions(+), 21 deletions(-) diff --git a/arch/m68k/Makefile b/arch/m68k/Makefile index 88d4d8bbecd6..ae6e29da3a3e 100644 --- a/arch/m68k/Makefile +++ b/arch/m68k/Makefile @@ -32,30 +32,33 @@ endif # compiler cpu type flag. # ifndef CONFIG_M68040 -cpuflags-$(CONFIG_M68060) := -m68060 +cpuflags-$(CONFIG_M68060) = -m68060 endif ifndef CONFIG_M68060 -cpuflags-$(CONFIG_M68040) := -m68040 +cpuflags-$(CONFIG_M68040) = -m68040 endif -cpuflags-$(CONFIG_M68030) := -cpuflags-$(CONFIG_M68020) := -cpuflags-$(CONFIG_M68000) := -m68000 -cpuflags-$(CONFIG_M5441x) := $(call cc-option,-mcpu=54455,-mcfv4e) -cpuflags-$(CONFIG_M54xx) := $(call cc-option,-mcpu=5475,-m5200) -cpuflags-$(CONFIG_M5407) := $(call cc-option,-mcpu=5407,-m5200) -cpuflags-$(CONFIG_M532x) := $(call cc-option,-mcpu=532x,-m5307) -cpuflags-$(CONFIG_M537x) := $(call cc-option,-mcpu=537x,-m5307) -cpuflags-$(CONFIG_M5307) := $(call cc-option,-mcpu=5307,-m5200) -cpuflags-$(CONFIG_M528x) := $(call cc-option,-mcpu=528x,-m5307) -cpuflags-$(CONFIG_M5275) := $(call cc-option,-mcpu=5275,-m5307) -cpuflags-$(CONFIG_M5272) := $(call cc-option,-mcpu=5272,-m5307) -cpuflags-$(CONFIG_M5271) := $(call cc-option,-mcpu=5271,-m5307) -cpuflags-$(CONFIG_M523x) := $(call cc-option,-mcpu=523x,-m5307) -cpuflags-$(CONFIG_M525x) := $(call cc-option,-mcpu=5253,-m5200) -cpuflags-$(CONFIG_M5249) := $(call cc-option,-mcpu=5249,-m5200) -cpuflags-$(CONFIG_M520x) := $(call cc-option,-mcpu=5208,-m5200) -cpuflags-$(CONFIG_M5206e) := $(call cc-option,-mcpu=5206e,-m5200) -cpuflags-$(CONFIG_M5206) := $(call cc-option,-mcpu=5206,-m5200) +cpuflags-$(CONFIG_M68030) = +cpuflags-$(CONFIG_M68020) = +cpuflags-$(CONFIG_M68000) = -m68000 +cpuflags-$(CONFIG_M5441x) = $(call cc-option,-mcpu=54455,-mcfv4e) +cpuflags-$(CONFIG_M54xx) = $(call cc-option,-mcpu=5475,-m5200) +cpuflags-$(CONFIG_M5407) = $(call cc-option,-mcpu=5407,-m5200) +cpuflags-$(CONFIG_M532x) = $(call cc-option,-mcpu=532x,-m5307) +cpuflags-$(CONFIG_M537x) = $(call cc-option,-mcpu=537x,-m5307) +cpuflags-$(CONFIG_M5307) = $(call cc-option,-mcpu=5307,-m5200) +cpuflags-$(CONFIG_M528x) = $(call cc-option,-mcpu=528x,-m5307) +cpuflags-$(CONFIG_M5275) = $(call cc-option,-mcpu=5275,-m5307) +cpuflags-$(CONFIG_M5272) = $(call cc-option,-mcpu=5272,-m5307) +cpuflags-$(CONFIG_M5271) = $(call cc-option,-mcpu=5271,-m5307) +cpuflags-$(CONFIG_M523x) = $(call cc-option,-mcpu=523x,-m5307) +cpuflags-$(CONFIG_M525x) = $(call cc-option,-mcpu=5253,-m5200) +cpuflags-$(CONFIG_M5249) = $(call cc-option,-mcpu=5249,-m5200) +cpuflags-$(CONFIG_M520x) = $(call cc-option,-mcpu=5208,-m5200) +cpuflags-$(CONFIG_M5206e) = $(call cc-option,-mcpu=5206e,-m5200) +cpuflags-$(CONFIG_M5206) = $(call cc-option,-mcpu=5206,-m5200) + +# Evaluate tune cc-option calls now +cpuflags-y := $(cpuflags-y) KBUILD_AFLAGS += $(cpuflags-y) KBUILD_CFLAGS += $(cpuflags-y) -- 2.25.1