kernel: Make KERNEL_MAKEOPTS recursively expanded

KERNEL_MAKEOPTS will get expanded when it is used and not when it is
defined in the kernel.mk file now. This fixes problems finding dependent
kernel modules when it is used by a kernel module package.

Without this change the build of packages which depend on other out of
tree modules failed when they used KERNEL_MAKE because some symbols could
not be found. This happened because KERNEL_MAKE_FLAGS which contains a
"if $(__package_mk)" was  evaluated where KERNEL_MAKEOPTS was defined
and not when the KERNEL_MAKE was used. For packages which included
kernel.mk before package.mk we saw this problem. One workaround
was to use the correct include order and the other one was to not
use KERNEL_MAKE_FLAGS, but copy its content.

Signed-off-by: Hauke Mehrtens <hmehrtens@maxlinear.com>
(cherry picked from commit 06ad3adeecc27859313e60c173c435d45ac2b345)

diff --git a/include/kernel.mk b/include/kernel.mk
index 070d1bca759d8a71d63652b08ba4b7c5428d9cfb..d61e0c2677c3a12565a3d99e7e6cfa4da03a921b 100644 (file)
--- a/include/kernel.mk
+++ b/include/kernel.mk
@@ -126,7 +126,7 @@ ifeq ($(call qstrip,$(CONFIG_EXTERNAL_KERNEL_TREE))$(call qstrip,$(CONFIG_KERNEL
        KERNELRELEASE=$(LINUX_VERSION)
 endif
 
-KERNEL_MAKEOPTS := -C $(LINUX_DIR) $(KERNEL_MAKE_FLAGS)
+KERNEL_MAKEOPTS = -C $(LINUX_DIR) $(KERNEL_MAKE_FLAGS)
 
 ifdef CONFIG_USE_SPARSE
   KERNEL_MAKEOPTS += C=1 CHECK=$(STAGING_DIR_HOST)/bin/sparse