On Mon, 18 Aug 2025 10:16:35 +0200 Kevin Brodsky kevin.brodsky@arm.com wrote:
# Avoid accidental wrong builds, due to built-in rules working just a little # bit too well--but not quite as well as required for our situation here. # @@ -35,6 +34,7 @@ MAKEFLAGS += --no-builtin-rules CFLAGS = -Wall -O2 -I $(top_srcdir) $(EXTRA_CFLAGS) $(KHDR_INCLUDES) $(TOOLS_INCLUDES) CFLAGS += -Wunreachable-code +CFLAGS += -Wunused -Wunused-parameter -Wunused-function -Wunused-label -Wunused-variable -Wunused-value
-Wall implies all of these except -Wunused-parameter (at least according to gcc(1)).
As to -Wunused-parameter I am frankly not convinced it's worth the hassle. We're getting 90 lines changed in patch 6-8 just to mark parameters as unused, in other words noise to keep the compiler happy. It is not enabled by default in the kernel proper precisely because it is so noisy when callbacks are involved.
Yeah, we rely upon unused parameters in a million places:
#else static inline void some_stub_function(type1 arg2, type2 arg2) { } #endif