buildrootschalter/package/ccache/ccache.mk
Thomas Petazzoni f044e03776 ccache: set COMPILERCHECK to 'none'
This allows ccache to re-use its cache contents even if the compiler
binary mtime has changed. It is the simplest approach to solve this
problem, and it works for the internal, external and crosstool-ng
toolchain backends.

Of course, it leaves the user responsible for invalidating the cache
when necessary, but there doesn't seem to be a real good solution that
allows both to: 1/ keep the cache contents accross builds and re-use
it and 2/ invalidate the cache automatically when the compiler chances
in an incompatible way.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2012-03-08 22:56:33 +01:00

53 lines
1.9 KiB
Makefile

#############################################################
#
# ccache
#
#############################################################
CCACHE_VERSION = 3.1.7
CCACHE_SITE = http://samba.org/ftp/ccache
CCACHE_SOURCE = ccache-$(CCACHE_VERSION).tar.bz2
# When ccache is being built for the host, ccache is not yet
# available, so we have to use the special C compiler without the
# cache.
HOST_CCACHE_CONF_ENV = \
CC="$(HOSTCC_NOCCACHE)"
# Force ccache to use its internal zlib. The problem is that without
# this, ccache would link against the zlib of the build system, but we
# might build and install a different version of zlib in $(O)/host
# afterwards, which ccache will pick up. This might break if there is
# a version mismatch. A solution would be to add host-zlib has a
# dependency of ccache, but it would require tuning the zlib .mk file
# to use HOSTCC_NOCCACHE as the compiler. Instead, we take the easy
# path: tell ccache to use its internal copy of zlib, so that ccache
# has zero dependency besides the C library.
HOST_CCACHE_CONF_OPT += ccache_cv_zlib_1_2_3=no
# We directly hardcode configuration into the binary, as it is much
# easier to handle than passing an environment variable. Our
# configuration is:
# - the cache location
# - the fact that ccache shouldn't use the compiler binary mtime to
# - detect a change in the compiler, because in the context of
# - Buildroot, that completely defeats the purpose of ccache. Of
# - course, that leaves the user responsible for purging its cache
# - when the compiler changes.
define HOST_CCACHE_FIX_CCACHE_DIR
sed -i 's,getenv("CCACHE_DIR"),"$(CCACHE_CACHE_DIR)",' $(@D)/ccache.c
sed -i 's,getenv("CCACHE_COMPILERCHECK"),"none",' $(@D)/ccache.c
endef
HOST_CCACHE_POST_CONFIGURE_HOOKS += \
HOST_CCACHE_FIX_CCACHE_DIR
$(eval $(call AUTOTARGETS))
$(eval $(call AUTOTARGETS,host))
ifeq ($(BR2_CCACHE),y)
ccache-stats: host-ccache
$(Q)$(CCACHE) -s
endif