From fe7c36c7bde12190341722af69358e42171162f3 Mon Sep 17 00:00:00 2001 From: Josh Triplett Date: Mon, 23 Dec 2013 13:56:06 -0800 Subject: [PATCH] Makefile: Build with -Werror=date-time if the compiler supports it GCC 4.9 and newer have a new warning -Wdate-time, which warns on any use of __DATE__, __TIME__, or __TIMESTAMP__, which would make the build non-deterministic. Now that the kernel does not use any of those macros, turn on -Werror=date-time if available, to keep it that way. The kernel already (optionally) records this information at build time in a single place; other kernel code should not duplicate that. Signed-off-by: Josh Triplett Signed-off-by: Michal Marek --- Makefile | 3 +++ 1 file changed, 3 insertions(+) diff --git a/Makefile b/Makefile index 455fd484b20e..731e3ce5b9ab 100644 --- a/Makefile +++ b/Makefile @@ -682,6 +682,9 @@ KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int) # require functions to have arguments in prototypes, not empty 'int foo()' KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes) +# Prohibit date/time macros, which would make the build non-deterministic +KBUILD_CFLAGS += $(call cc-option,-Werror=date-time) + # use the deterministic mode of AR if available KBUILD_ARFLAGS := $(call ar-option,D) -- 2.20.1