In the above example, -Wno-unused-but-set-variable will be added to
KBUILD_CFLAGS only if gcc really accepts it.
- cc-version
- cc-version returns a numerical version of the $(CC) compiler version.
- The format is <major><minor> where both are two digits. So for example
- gcc 3.41 would return 0341.
- cc-version is useful when a specific $(CC) version is faulty in one
- area, for example -mregparm=3 was broken in some gcc versions
- even though the option was accepted by gcc.
-
- Example:
- #arch/x86/Makefile
- cflags-y += $(shell \
- if [ $(cc-version) -ge 0300 ] ; then \
- echo "-mregparm=3"; fi ;)
-
- In the above example, -mregparm=3 is only used for gcc version greater
- than or equal to gcc 3.0.
-
cc-ifversion
cc-ifversion tests the version of $(CC) and equals the fourth parameter
if version expression is true, or the fifth (if given) if the version
cc-disable-warning = $(call try-run,\
$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
-# cc-version
-cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
-
# cc-ifversion
# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
-cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4))
+cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4))
# cc-ldoption
# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)