[U-Boot] Build error: caused by CONFIG_SPL_LOG_CONSOLE

[U.Mutlu]

If I activate "Enable logging support in SPL" (ie. CONFIG_SPL_LOG_CONSOLE),
ie. the following window in make menuconfig:

   Logging  --->

     [*] Enable logging support
     [*]   Enable logging support in SPL
     [*]   Enable logging support in TPL
     (5)   Maximum log level to record
     (3) Maximum log level to record in SPL (NEW)
     (3) Maximum log level to record in TPL
     (6) Default logging level to display
     [*] Allow log output to the console
     [*] Allow log output to the console in SPL (NEW)
     [*] Allow log output to the console in SPL
     [ ] Provide a test for logging
     [*] Log all functions which return an error

then the build fails as follows (paths sanitized):

arm-linux-gnueabihf-ld.bfd: common/built-in.o: in function `log_get_cat_name':
/.../u-boot/common/log.c:48: undefined reference to `uclass_get_name'
arm-linux-gnueabihf-ld.bfd: common/built-in.o: in function `_log':
/.../u-boot/common/log.c:212: undefined reference to `vsnprintf'
scripts/Makefile.spl:384: recipe for target 'spl/u-boot-spl' failed
make[1]: *** [spl/u-boot-spl] Error 1
Makefile:1664: recipe for target 'spl/u-boot-spl' failed
make: *** [spl/u-boot-spl] Error 2


Deactivating "Enable logging support in SPL" builds ok.


Version:
U-Boot 2019.04-00077-g48ff1bc4f0
(using stock git source tree w/o any own modifications)

Platform:
CONFIG_ARM=y
CONFIG_SYS_ARCH="arm"
CONFIG_SYS_CPU="armv7"
CONFIG_SYS_SOC="sunxi"
CONFIG_SYS_BOARD="sunxi"
CONFIG_SYS_CONFIG_NAME="sun7i"
CONFIG_DEFAULT_DEVICE_TREE="sun7i-a20-lamobo-r1"