[PATCH] kbuild: support W=c and W=e shorthands for Kconfig

Masahiro Yamada
2023-11-23T09:05:53Z

KCONFIG_WARN_UNKNOWN_SYMBOLS=1 and KCONFIG_WERROR=1 are descriptive
and suitable in scripting, but it is tedious to type them from the
command line.

Associate them with KBUILD_EXTRA_WARN (and the W= shorthand).

Support a new letter 'c' for KBUILD_EXTRA_WARN to enable extra checks
in Kconfig. You can still manage compiler warnings (W=1) and Kconfig
warnings (W=c) independently.

Reuse the letter 'e' to turn Kconfig warnings into errors.

As usual, you can combine multiple letters in KCONFIG_EXTRA_WARN.

$ KCONFIG_WARN_UNKNOWN_SYMBOLS=1 KCONFIG_WERROR=1 make defconfig

can be shortened to:

$ KBUILD_EXTRA_WARN=ce make defconfig

or, even shorter:

$ make W=ce defconfig

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

Makefile | 10 ++++++++++
scripts/Makefile.extrawarn | 9 ---------
scripts/kconfig/Makefile | 8 ++++++++
3 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/Makefile b/Makefile
index f128a1a1b1a0..91947f722b77 100644
--- a/Makefile
+++ b/Makefile
@@ -155,6 +155,15 @@ endif

export KBUILD_EXTMOD

+# backward compatibility
+KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)
+
+ifeq ("$(origin W)", "command line")
+ KBUILD_EXTRA_WARN := $(W)
+endif
+
+export KBUILD_EXTRA_WARN
+
# Kbuild will save output files in the current working directory.
# This does not need to match to the root of the kernel source tree.
#
@@ -1659,6 +1668,7 @@ help:
@echo ' 1: warnings which may be relevant and do not occur too often'
@echo ' 2: warnings which occur quite often but may still be relevant'
@echo ' 3: more obscure warnings, can most likely be ignored'
+ @echo ' c: extra checks in the configuration stage (Kconfig)'
@echo ' e: warnings are being treated as errors'
@echo ' Multiple levels can be combined with W=12 or W=123'
@$(if $(dtstree), \
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 2fe6f2828d37..3f94915fab37 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -80,15 +80,6 @@ KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init)
# Warn if there is an enum types mismatch
KBUILD_CFLAGS += $(call cc-option,-Wenum-conversion)

-# backward compatibility
-KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)
-
-ifeq ("$(origin W)", "command line")
- KBUILD_EXTRA_WARN := $(W)
-endif
-
-export KBUILD_EXTRA_WARN
-
#
# W=1 - warnings which may be relevant and do not occur too often
#
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index 4eee155121a8..322c061b464d 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -27,6 +27,14 @@ KCONFIG_DEFCONFIG_LIST += \
endif
KCONFIG_DEFCONFIG_LIST += arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)

+ifneq ($(findstring c, $(KBUILD_EXTRA_WARN)),)
+export KCONFIG_WARN_UNKNOWN_SYMBOLS=1
+endif
+
+ifneq ($(findstring e, $(KBUILD_EXTRA_WARN)),)
+export KCONFIG_WERROR=1
+endif
+
# We need this, in case the user has it in its environment
unexport CONFIG_

--
2.40.1