Few drivers use ccflags-* in their top directory to enable -DDEBUG, but don't have config options to enable debug in the sub-directories, or they use per subdirectory ccflags-* to have DEBUG with the same kconfig option.
Considering they intends to enable debug for all the files under the directory with the same kconfig option, it will be clearer to use subdir-ccflags-* instead of ccflags-* to inherit the debug settings from Kconfig when traversing subdirectories.
We primarily find this issue when debugging PCIe and thought other drivers may also have this issues. Previous discussion can be find at https://lore.kernel.org/linux-pci/1612438215-33105-1-git-send-email-yangyico...
Change since v1: - reword the commits to illustrate the reasons of the change and the benefits. v1: https://lore.kernel.org/lkml/1612518255-23052-1-git-send-email-yangyicong@hi...
Junhao He (4): driver core: Use subdir-ccflags-* to inherit debug flag hwmon: Use subdir-ccflags-* to inherit debug flag pps: Use subdir-ccflags-* to inherit debug flag staging: comedi: Use subdir-ccflags-* to inherit debug flag
drivers/base/Makefile | 2 +- drivers/base/power/Makefile | 2 -- drivers/hwmon/Makefile | 2 +- drivers/pps/Makefile | 2 +- drivers/staging/comedi/Makefile | 2 +- drivers/staging/comedi/drivers/Makefile | 1 - drivers/staging/comedi/drivers/tests/Makefile | 2 -- drivers/staging/comedi/kcomedilib/Makefile | 2 -- 8 files changed, 4 insertions(+), 11 deletions(-)