Hi Greg, On 2021/2/5 17:53, Greg KH wrote: > On Fri, Feb 05, 2021 at 05:44:12PM +0800, Yicong Yang wrote: >> From: Junhao He <hejunhao2@xxxxxxxxxxxxx> >> >> Use subdir-ccflags-* instead of ccflags-* to inherit the debug >> settings from Kconfig when traversing subdirectories. > > That says what you do, but not _why_ you are doing it. i'll illustrate the reason and reword the commit. > > What does this offer in benefit of the existing way? What is it fixing? > Why do this "churn"? currently we have added ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG in the Makefile of driver/base and driver/base/power, but not in the subdirectory driver/base/firmware_loader. we cannot turn the debug on for subdirectory firmware_loader if we config DEBUG_DRIVER and there is no kconfig option for the it. as there is no other debug config in the subdirectory of driver/base, CONFIG_DEBUG_DRIVER may also mean turn on the debug in the subdirectories, so use subdir-ccflags-* instead for the -DDEBUG will allow us to enable debug for all the subdirectories. Thanks, Yicong > > thanks, > > greg k-h > > . >
