debugging Kconfig (and Kbuild) (via printf!)

Kconfig

diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include
index a5fe72c504ff..b59db288da28 100644
--- a/scripts/Kconfig.include
+++ b/scripts/Kconfig.include
@@ -25,7 +25,7 @@ failure = $(if-success,$(1),n,y)
 
 # $(cc-option,<flag>)
 # Return y if the compiler supports <flag>, n otherwise
-cc-option = $(success,mkdir .tmp_$$$$; trap "rm -rf .tmp_$$$$" EXIT; $(CC) -Werror $(CLANG_FLAGS) $(1) -c -x c /dev/null -o .tmp_$$$$/tmp.o)
+cc-option = $(success,mkdir .tmp_$$$$; trap "rm -rf .tmp_$$$$" EXIT; $(CC) -Werror $(CLANG_FLAGS) $(1) -c -x c /dev/null -o .tmp_$$$$/tmp.o; echo $(CC) -Werror $(CLANG_FLAGS) $(1) -c -x c /dev/null >> log.txt)
 
 # $(ld-option,<flag>)
 # Return y if the linker supports <flag>, n otherwise