Apply memoization to cc-option macro by caching the results of the gcc calls. This macro is called very often so using cached results leads to faster compilation times.
The old behaviour can be restored by defining the config option CONFIG_CC_OPT_CACHE_DISABLE=y.
Signed-off-by: Daniel Schwierzeck daniel.schwierzeck@googlemail.com --- Changes for v3: - reworked handling of non-working gcc options - add config option CONFIG_CC_OPT_CACHE_DISABLE
Changes for v2: - move cache file to $(obj)/include/generated - reworked completely - cache also non-working gcc options - remove CACHE_CC_OPTIONS config switch and enable this optimization by default
config.mk | 20 ++++++++++++++++++-- 1 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/config.mk b/config.mk index 918cffe..ddaa477 100644 --- a/config.mk +++ b/config.mk @@ -107,8 +107,24 @@ HOSTCFLAGS += -pedantic # Option checker (courtesy linux kernel) to ensure # only supported compiler options are used # -cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \ - > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;) +CC_OPTIONS_CACHE_FILE := $(OBJTREE)/include/generated/cc_options.mk + +$(if $(wildcard $(CC_OPTIONS_CACHE_FILE)),,\ + $(shell mkdir -p $(dir $(CC_OPTIONS_CACHE_FILE)))) + +-include $(CC_OPTIONS_CACHE_FILE) + +cc-option-sys = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \ + > /dev/null 2>&1; then \ + echo 'CC_OPTIONS += $(strip $1)' >> $(CC_OPTIONS_CACHE_FILE); \ + echo "$(1)"; fi) + +ifeq ($(CONFIG_CC_OPT_CACHE_DISABLE),y) +cc-option = $(strip $(if $(call cc-option-sys,$1),$1,$2)) +else +cc-option = $(strip $(if $(findstring $1,$(CC_OPTIONS)),$1,\ + $(if $(call cc-option-sys,$1),$1,$2))) +endif
# # Include the make variables (CC, etc...)