kbuild: move CFLAGS_{KASAN,UBSAN,KCSAN} exports to relevant Makefiles
Move CFLAGS_KASAN*, CFLAGS_UBSAN, CFLAGS_KCSAN to Makefile.kasan,
Makefile.ubsan, Makefile.kcsan, respectively.
This commit also avoids the same -fsanitize=* flags being added to
CFLAGS_UBSAN multiple times.
Prior to this commit, the ubsan flags were appended by the '+='
operator, without any initialization. Some build targets such as
'make bindeb-pkg' recurses to the top Makefile, and ended up with
adding the same flags to CFLAGS_UBSAN twice.
Clear CFLAGS_UBSAN with ':=' to make it a simply expanded variable.
This is better than a recursively expanded variable, which evaluates
$(call cc-option, ...) multiple times before Kbuild starts descending
to subdirectories.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Marco Elver <elver@google.com>
diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan
index 1532f1a..1e000cc 100644
--- a/scripts/Makefile.kasan
+++ b/scripts/Makefile.kasan
@@ -47,3 +47,5 @@
$(instrumentation_flags)
endif # CONFIG_KASAN_SW_TAGS
+
+export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE