| Message ID | 1465276681-23700-1-git-send-email-yamada.masahiro@socionext.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/Makefile b/Makefile index 8d1301a..58c06be 100644 --- a/Makefile +++ b/Makefile @@ -767,7 +767,7 @@ KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once) endif # arch Makefile may override CC so keep this after arch Makefile is included -NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include) +NOSTDINC_FLAGS := -nostdinc -isystem $(shell $(CC) -print-file-name=include) CHECKFLAGS += $(NOSTDINC_FLAGS) # warn about C99 declaration after statement
For package building, the scripts/package/Makefile invokes "$(MAKE) KBUILD_SRC=", so the top Makefile is invoked recursively. Notice NOSTDINC_FLAGS is exported and assigned with "+=", not ":=". It means, NOSTDINC_FLAGS is accumulated in the call loop of package build: top Makefile -> scripts/package/Makefile -> top Makefile. Before, it was not a big deal because GCC just ignores the repeated compile options, and $(call if_changed,...) compared the old/new commands as a set of arguments. However, the situation was changed by commit 9c8fa9bc08f6 ("kbuild: fix if_change and friends to consider argument order"). Now Kbuild compares old/new commands more precisely. Since then, "make" followed by "make targz-pkg" always rebuilds the whole kernel. The NOSTDINC_FLAGS is added just once for "make", whilst twice for "make targz-pkg" as mentioned above. So, Kbuild considers that the build command has changed despite that we want a tarball straight away if everything is already built. The easiest way to fix this problem is to change "+=" to ":=" for NOSTDINC_FLAGS assignment. This effectively reverts commit e8f5bdb02ce0 ("[PATCH] Makefile include path ordering"). Its log says that the arch Makefile may override the include path order, but I see no arch Makefile touching NOSTDINC_FLAGS. So, this change should have no impact unless something outside of the kernel needs to override it. Reported-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> --- This patch is fixing the problem reported by: http://www.gossamer-threads.com/lists/linux/kernel/2454440 Paulo, Thanks for your report! Rik, This patch is reverting your commit applied more than a decide ago. As far as I see the kernel tree, I am not sure if it is still needed. I am not familiar with Xen at all, so your review is very appreciated. Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)