build: add support for git submodules with CONFIG_SRC_TREE_OVERRIDE

Also work around an issue where git would store the modified workdir in
the submodule git config files

Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/include/package.mk b/include/package.mk
index 78ea5d0ef8b73e758466b48f4a9d652daae7d59c..9912c86d6b34207e0698feacf49e4a995dd32f76 100644 (file)
--- a/include/package.mk
+++ b/include/package.mk
@@ -120,7 +120,12 @@ ifdef USE_GIT_TREE
   define Build/Prepare/Default
        mkdir -p $(PKG_BUILD_DIR)
        ln -s $(CURDIR)/git-src $(PKG_BUILD_DIR)/.git
-       ( cd $(PKG_BUILD_DIR); git checkout .)
+       ( cd $(PKG_BUILD_DIR); \
+               git checkout .; \
+               git submodule update --recursive; \
+               git submodule foreach git config --unset core.worktree; \
+               git submodule foreach git checkout .; \
+       )
   endef
 endif
 ifdef USE_SOURCE_DIR