git/config.mak.dev
Jeff King a219a6739c config.mak.dev: enable -Wunused-parameter by default
Having now removed or annotated all of the unused function parameters in
our code base, I found that each instance falls into one of three
categories:

  1. ignoring the parameter is a bug (e.g., a function takes a ptr/len
     pair, but ignores the length). Detecting these helps us find the
     bugs.

  2. the parameter is unnecessary (and usually left over from a
     refactoring or earlier iteration of a patches series). Removing
     these cleans up the code.

  3. the function has to conform to a specific interface (because it's
     used via a function pointer, or matches something on the other side
     of an #ifdef). These ones are annoying, but annotating them with
     UNUSED is not too bad (especially if the compiler tells you about
     the problem promptly).

Certainly instances of (3) are more common than (1), but after finding
all of these, I think there were enough cases of (1) that it justifies
the work in annotating all of the (3)s.

And since the code base is now at a spot where we compile cleanly with
-Wunused-parameter, turning it on will make it the responsibility of
individual patch writers going forward.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-28 09:51:18 -07:00

102 lines
3.3 KiB
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ifndef COMPILER_FEATURES
COMPILER_FEATURES := $(shell ./detect-compiler $(CC))
endif
ifeq ($(filter no-error,$(DEVOPTS)),)
DEVELOPER_CFLAGS += -Werror
SPARSE_FLAGS += -Wsparse-error
endif
DEVELOPER_CFLAGS += -Wall
ifeq ($(filter no-pedantic,$(DEVOPTS)),)
DEVELOPER_CFLAGS += -pedantic
ifneq ($(or $(filter gcc5,$(COMPILER_FEATURES)),$(filter clang4,$(COMPILER_FEATURES))),)
DEVELOPER_CFLAGS += -Wpedantic
ifneq ($(filter gcc10,$(COMPILER_FEATURES)),)
ifeq ($(uname_S),MINGW)
DEVELOPER_CFLAGS += -Wno-pedantic-ms-format
endif
endif
endif
endif
ifneq ($(uname_S),FreeBSD)
ifneq ($(or $(filter gcc6,$(COMPILER_FEATURES)),$(filter clang7,$(COMPILER_FEATURES))),)
DEVELOPER_CFLAGS += -std=gnu99
endif
else
# FreeBSD cannot limit to C99 because its system headers unconditionally
# rely on C11 features.
endif
DEVELOPER_CFLAGS += -Wdeclaration-after-statement
DEVELOPER_CFLAGS += -Wformat-security
DEVELOPER_CFLAGS += -Wold-style-definition
DEVELOPER_CFLAGS += -Woverflow
DEVELOPER_CFLAGS += -Wpointer-arith
DEVELOPER_CFLAGS += -Wstrict-prototypes
DEVELOPER_CFLAGS += -Wunused
DEVELOPER_CFLAGS += -Wvla
DEVELOPER_CFLAGS += -Wwrite-strings
DEVELOPER_CFLAGS += -fno-common
ifneq ($(filter clang4,$(COMPILER_FEATURES)),)
DEVELOPER_CFLAGS += -Wtautological-constant-out-of-range-compare
endif
ifneq ($(or $(filter gcc6,$(COMPILER_FEATURES)),$(filter clang4,$(COMPILER_FEATURES))),)
DEVELOPER_CFLAGS += -Wextra
# if a function is public, there should be a prototype and the right
# header file should be included. If not, it should be static.
DEVELOPER_CFLAGS += -Wmissing-prototypes
ifeq ($(filter extra-all,$(DEVOPTS)),)
# These are disabled because we have these all over the place.
DEVELOPER_CFLAGS += -Wno-empty-body
DEVELOPER_CFLAGS += -Wno-missing-field-initializers
DEVELOPER_CFLAGS += -Wno-sign-compare
endif
endif
# uninitialized warnings on gcc 4.9.2 in xdiff/xdiffi.c and config.c
# not worth fixing since newer compilers correctly stop complaining
#
# Likewise, gcc older than 4.9 complains about initializing a
# struct-within-a-struct using just "{ 0 }"
ifneq ($(filter gcc4,$(COMPILER_FEATURES)),)
ifeq ($(filter gcc5,$(COMPILER_FEATURES)),)
DEVELOPER_CFLAGS += -Wno-uninitialized
DEVELOPER_CFLAGS += -Wno-missing-braces
endif
endif
# Old versions of clang complain about initializaing a
# struct-within-a-struct using just "{0}" rather than "{{0}}". This
# error is considered a false-positive and not worth fixing, because
# new clang versions do not, so just disable it.
#
# The "bug" was fixed in upstream clang 9.
#
# Complicating this is that versions of clang released by Apple have
# their own version numbers (associated with the corresponding version
# of XCode) unrelated to the official clang version numbers.
#
# The bug was fixed in Apple clang 12.
#
ifneq ($(filter clang1,$(COMPILER_FEATURES)),) # if we are using clang
ifeq ($(uname_S),Darwin) # if we are on darwin
ifeq ($(filter clang12,$(COMPILER_FEATURES)),) # if version < 12
DEVELOPER_CFLAGS += -Wno-missing-braces
endif
else # not darwin
ifeq ($(filter clang9,$(COMPILER_FEATURES)),) # if version < 9
DEVELOPER_CFLAGS += -Wno-missing-braces
endif
endif
endif
# https://bugzilla.redhat.com/show_bug.cgi?id=2075786
ifneq ($(filter gcc12,$(COMPILER_FEATURES)),)
DEVELOPER_CFLAGS += -Wno-error=stringop-overread
endif
GIT_TEST_PERL_FATAL_WARNINGS = YesPlease