package/qt5/qt5base: use ccache for building host code

qt5 currently doesn't use HOSTCC/HOSTCXX, so it doesn't use ccache
when building all its host code (especially qmake). This means that
even with ccache enabled and a hot cache, it still takes a long time
to build qt5base.

Before this patch, building qt5base takes:

 - 446 seconds with a cold ccache
 - 185 seconds with a hot ccache

This is because the ccache is not used for host code.

After this patch, building qt5base takes:

 - 450 seconds with a cold ccache
 - 15 seconds with a hot ccache

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Reviewed-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

diff --git a/package/qt5/qt5base/qt5base.mk b/package/qt5/qt5base/qt5base.mk
index 2b6fd39267e46bf2b946c7c4009549984cfe9b30..ec3d7042f110920aac845ebe9f28e773a0927abc 100644 (file)
--- a/package/qt5/qt5base/qt5base.mk
+++ b/package/qt5/qt5base/qt5base.mk
@@ -271,6 +271,13 @@ define QT5BASE_CONFIGURE_ARCH_CONFIG
 endef
 endif
 
+# This allows to use ccache when available
+define QT5BASE_CONFIGURE_HOSTCC
+       $(SED) 's,^QMAKE_COMPILER\s*=.*,QMAKE_COMPILER=$(HOSTCC),' $(@D)/mkspecs/common/g++-base.conf
+       $(SED) 's,^QMAKE_CC\s*=.*,QMAKE_CC=$(HOSTCC),' $(@D)/mkspecs/common/g++-base.conf
+       $(SED) 's,^QMAKE_CXX\s*=.*,QMAKE_CXX=$(HOSTCXX),' $(@D)/mkspecs/common/g++-base.conf
+endef
+
 define QT5BASE_CONFIGURE_CMDS
        mkdir -p $(@D)/mkspecs/devices/linux-buildroot-g++/
        sed 's/@EGLFS_DEVICE@/$(QT5BASE_EGLFS_DEVICE)/g' \
@@ -281,6 +288,7 @@ define QT5BASE_CONFIGURE_CMDS
        $(QT5BASE_CONFIGURE_CONFIG_FILE)
        touch $(QT5BASE_ARCH_CONFIG_FILE)
        $(QT5BASE_CONFIGURE_ARCH_CONFIG)
+       $(QT5BASE_CONFIGURE_HOSTCC)
        (cd $(@D); \
                $(TARGET_MAKE_ENV) \
                PKG_CONFIG="$(PKG_CONFIG_HOST_BINARY)" \