[U-Boot] [PATCH] config.mk: Add -Wundef to CFLAGS

[Masahiro Yamada]

Hello Albert

> Will the patch cause some targets to break? 

I don't think so
because -Wundef option just prints warnings.


GCC manual says:
-Wundef
Warn if an undefined identifier is evaluated in an ‘#if’ directive.



After applying this patch,
I noticed warnings like follows:

include/common.h:240:11: warning: "CONFIG_ENV_ADDR" is not defined [-Wundef]
include/common.h:240:46: warning: "CONFIG_SYS_MONITOR_BASE" is not defined [-Wundef]
include/common.h:241:3: warning: "CONFIG_ENV_ADDR" is not defined [-Wundef]
include/common.h:241:23: warning: "CONFIG_SYS_MONITOR_BASE" is not defined [-Wundef]
include/common.h:241:49: warning: "CONFIG_SYS_MONITOR_LEN" is not defined [-Wundef]


If this patch is applied soon, we have enough time to fix warnings 
before u-boot-2013.10 release.

If I have time, I'd like to make effort to eliminate such warnings.
Of course, patches from other contributers are very welcome.


Best Regards
Masahiro Yamada