mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-15 10:17:20 +00:00
2f6a842484
GCC is more pedantic than clang about warning when a function doesn't handle undefined enum values (see GCC bug 87950). Clang's warning gives a more pragmatic coverage and should find any real bugs, so disable the warning for GCC rather than adding __unreachable annotations to appease GCC. Reviewed by: imp, emaste Differential Revision: https://reviews.freebsd.org/D34147
316 lines
10 KiB
Makefile
316 lines
10 KiB
Makefile
# $FreeBSD$
|
|
|
|
#
|
|
# Warning flags for compiling the kernel and components of the kernel:
|
|
#
|
|
CWARNFLAGS?= -Wall -Wnested-externs -Wstrict-prototypes \
|
|
-Wmissing-prototypes -Wpointer-arith -Wcast-qual \
|
|
-Wundef -Wno-pointer-sign ${FORMAT_EXTENSIONS} \
|
|
-Wmissing-include-dirs -fdiagnostics-show-option \
|
|
-Wno-unknown-pragmas \
|
|
${CWARNEXTRA}
|
|
#
|
|
# The following flags are next up for working on:
|
|
# -Wextra
|
|
|
|
# Disable a few warnings for clang, since there are several places in the
|
|
# kernel where fixing them is more trouble than it is worth, or where there is
|
|
# a false positive.
|
|
.if ${COMPILER_TYPE} == "clang"
|
|
NO_WCONSTANT_CONVERSION= -Wno-error=constant-conversion
|
|
NO_WSHIFT_COUNT_NEGATIVE= -Wno-shift-count-negative
|
|
NO_WSHIFT_COUNT_OVERFLOW= -Wno-shift-count-overflow
|
|
NO_WSELF_ASSIGN= -Wno-self-assign
|
|
NO_WUNNEEDED_INTERNAL_DECL= -Wno-error=unneeded-internal-declaration
|
|
NO_WSOMETIMES_UNINITIALIZED= -Wno-error=sometimes-uninitialized
|
|
NO_WCAST_QUAL= -Wno-error=cast-qual
|
|
NO_WTAUTOLOGICAL_POINTER_COMPARE= -Wno-tautological-pointer-compare
|
|
.if ${COMPILER_VERSION} >= 100000
|
|
NO_WMISLEADING_INDENTATION= -Wno-misleading-indentation
|
|
.endif
|
|
.if ${COMPILER_VERSION} >= 140000
|
|
NO_WBITWISE_INSTEAD_OF_LOGICAL= -Wno-bitwise-instead-of-logical
|
|
.endif
|
|
# Several other warnings which might be useful in some cases, but not severe
|
|
# enough to error out the whole kernel build. Display them anyway, so there is
|
|
# some incentive to fix them eventually.
|
|
CWARNEXTRA?= -Wno-error=tautological-compare -Wno-error=empty-body \
|
|
-Wno-error=parentheses-equality -Wno-error=unused-function \
|
|
-Wno-error=pointer-sign
|
|
CWARNEXTRA+= -Wno-error=shift-negative-value
|
|
CWARNEXTRA+= -Wno-address-of-packed-member
|
|
.if ${COMPILER_VERSION} >= 130000
|
|
CWARNFLAGS+= -Wno-error=unused-but-set-variable
|
|
.endif
|
|
.endif # clang
|
|
|
|
.if ${COMPILER_TYPE} == "gcc"
|
|
# Catch-all for all the things that are in our tree, but for which we're
|
|
# not yet ready for this compiler.
|
|
NO_WUNUSED_BUT_SET_VARIABLE = -Wno-unused-but-set-variable
|
|
CWARNEXTRA?= -Wno-error=address \
|
|
-Wno-error=aggressive-loop-optimizations \
|
|
-Wno-error=array-bounds \
|
|
-Wno-error=attributes \
|
|
-Wno-error=cast-qual \
|
|
-Wno-error=enum-compare \
|
|
-Wno-error=maybe-uninitialized \
|
|
-Wno-error=misleading-indentation \
|
|
-Wno-error=nonnull-compare \
|
|
-Wno-error=overflow \
|
|
-Wno-error=sequence-point \
|
|
-Wno-error=shift-overflow \
|
|
-Wno-error=tautological-compare \
|
|
-Wno-unused-but-set-variable
|
|
.if ${COMPILER_VERSION} >= 70100
|
|
CWARNEXTRA+= -Wno-error=stringop-overflow
|
|
.endif
|
|
.if ${COMPILER_VERSION} >= 70200
|
|
CWARNEXTRA+= -Wno-error=memset-elt-size
|
|
.endif
|
|
.if ${COMPILER_VERSION} >= 80000
|
|
CWARNEXTRA+= -Wno-error=packed-not-aligned
|
|
.endif
|
|
.if ${COMPILER_VERSION} >= 90100
|
|
CWARNEXTRA+= -Wno-address-of-packed-member \
|
|
-Wno-error=alloca-larger-than=
|
|
.endif
|
|
|
|
# GCC produces false positives for functions that switch on an
|
|
# enum (GCC bug 87950)
|
|
CWARNFLAGS+= -Wno-return-type
|
|
.endif # gcc
|
|
|
|
# This warning is utter nonsense
|
|
CWARNFLAGS+= -Wno-format-zero-length
|
|
|
|
# External compilers may not support our format extensions. Allow them
|
|
# to be disabled. WARNING: format checking is disabled in this case.
|
|
.if ${MK_FORMAT_EXTENSIONS} == "no"
|
|
FORMAT_EXTENSIONS= -Wno-format
|
|
.elif ${COMPILER_TYPE} == "clang"
|
|
FORMAT_EXTENSIONS= -D__printf__=__freebsd_kprintf__
|
|
.else
|
|
FORMAT_EXTENSIONS= -fformat-extensions
|
|
.endif
|
|
|
|
#
|
|
# On i386, do not align the stack to 16-byte boundaries. Otherwise GCC 2.95
|
|
# and above adds code to the entry and exit point of every function to align the
|
|
# stack to 16-byte boundaries -- thus wasting approximately 12 bytes of stack
|
|
# per function call. While the 16-byte alignment may benefit micro benchmarks,
|
|
# it is probably an overall loss as it makes the code bigger (less efficient
|
|
# use of code cache tag lines) and uses more stack (less efficient use of data
|
|
# cache tag lines). Explicitly prohibit the use of FPU, SSE and other SIMD
|
|
# operations inside the kernel itself. These operations are exclusively
|
|
# reserved for user applications.
|
|
#
|
|
# gcc:
|
|
# Setting -mno-mmx implies -mno-3dnow
|
|
# Setting -mno-sse implies -mno-sse2, -mno-sse3 and -mno-ssse3
|
|
#
|
|
# clang:
|
|
# Setting -mno-mmx implies -mno-3dnow and -mno-3dnowa
|
|
# Setting -mno-sse implies -mno-sse2, -mno-sse3, -mno-ssse3, -mno-sse41 and -mno-sse42
|
|
#
|
|
.if ${MACHINE_CPUARCH} == "i386"
|
|
CFLAGS.gcc+= -mpreferred-stack-boundary=2
|
|
CFLAGS.clang+= -mno-aes -mno-avx
|
|
CFLAGS+= -mno-mmx -mno-sse -msoft-float
|
|
INLINE_LIMIT?= 8000
|
|
.endif
|
|
|
|
.if ${MACHINE_CPUARCH} == "arm"
|
|
INLINE_LIMIT?= 8000
|
|
.endif
|
|
|
|
.if ${MACHINE_CPUARCH} == "aarch64"
|
|
# We generally don't want fpu instructions in the kernel.
|
|
CFLAGS += -mgeneral-regs-only
|
|
# Reserve x18 for pcpu data
|
|
CFLAGS += -ffixed-x18
|
|
INLINE_LIMIT?= 8000
|
|
.endif
|
|
|
|
#
|
|
# For RISC-V we specify the soft-float ABI (lp64) to avoid the use of floating
|
|
# point registers within the kernel. However, for kernels supporting hardware
|
|
# float (FPE), we have to include that in the march so we can have limited
|
|
# floating point support in context switching needed for that. This is different
|
|
# than userland where we use a hard-float ABI (lp64d).
|
|
#
|
|
# We also specify the "medium" code model, which generates code suitable for a
|
|
# 2GiB addressing range located at any offset, allowing modules to be located
|
|
# anywhere in the 64-bit address space. Note that clang and GCC refer to this
|
|
# code model as "medium" and "medany" respectively.
|
|
#
|
|
.if ${MACHINE_CPUARCH} == "riscv"
|
|
CFLAGS+= -march=rv64imafdc
|
|
CFLAGS+= -mabi=lp64
|
|
CFLAGS.clang+= -mcmodel=medium
|
|
CFLAGS.gcc+= -mcmodel=medany
|
|
INLINE_LIMIT?= 8000
|
|
|
|
.if ${LINKER_FEATURES:Mriscv-relaxations} == ""
|
|
CFLAGS+= -mno-relax
|
|
.endif
|
|
.endif
|
|
|
|
#
|
|
# For AMD64, we explicitly prohibit the use of FPU, SSE and other SIMD
|
|
# operations inside the kernel itself. These operations are exclusively
|
|
# reserved for user applications.
|
|
#
|
|
# gcc:
|
|
# Setting -mno-mmx implies -mno-3dnow
|
|
# Setting -mno-sse implies -mno-sse2, -mno-sse3, -mno-ssse3 and -mfpmath=387
|
|
#
|
|
# clang:
|
|
# Setting -mno-mmx implies -mno-3dnow and -mno-3dnowa
|
|
# Setting -mno-sse implies -mno-sse2, -mno-sse3, -mno-ssse3, -mno-sse41 and -mno-sse42
|
|
# (-mfpmath= is not supported)
|
|
#
|
|
.if ${MACHINE_CPUARCH} == "amd64"
|
|
CFLAGS.clang+= -mno-aes -mno-avx
|
|
CFLAGS+= -mcmodel=kernel -mno-red-zone -mno-mmx -mno-sse -msoft-float \
|
|
-fno-asynchronous-unwind-tables
|
|
INLINE_LIMIT?= 8000
|
|
.endif
|
|
|
|
#
|
|
# For PowerPC we tell gcc to use floating point emulation. This avoids using
|
|
# floating point registers for integer operations which it has a tendency to do.
|
|
# Also explicitly disable Altivec instructions inside the kernel.
|
|
#
|
|
.if ${MACHINE_CPUARCH} == "powerpc"
|
|
CFLAGS+= -mno-altivec -msoft-float
|
|
INLINE_LIMIT?= 15000
|
|
.endif
|
|
|
|
.if ${MACHINE_ARCH} == "powerpcspe"
|
|
CFLAGS.gcc+= -mno-spe
|
|
.endif
|
|
|
|
#
|
|
# Use dot symbols (or, better, the V2 ELF ABI) on powerpc64 to make
|
|
# DDB happy. ELFv2, if available, has some other efficiency benefits.
|
|
#
|
|
.if ${MACHINE_ARCH:Mpowerpc64*} != ""
|
|
CFLAGS+= -mabi=elfv2
|
|
.endif
|
|
|
|
#
|
|
# GCC 3.0 and above like to do certain optimizations based on the
|
|
# assumption that the program is linked against libc. Stop this.
|
|
#
|
|
CFLAGS+= -ffreestanding
|
|
|
|
#
|
|
# The C standard leaves signed integer overflow behavior undefined.
|
|
# gcc and clang opimizers take advantage of this. The kernel makes
|
|
# use of signed integer wraparound mechanics so we need the compiler
|
|
# to treat it as a wraparound and not take shortcuts.
|
|
#
|
|
CFLAGS+= -fwrapv
|
|
|
|
#
|
|
# GCC SSP support
|
|
#
|
|
.if ${MK_SSP} != "no"
|
|
CFLAGS+= -fstack-protector
|
|
.endif
|
|
|
|
#
|
|
# Retpoline speculative execution vulnerability mitigation (CVE-2017-5715)
|
|
#
|
|
.if defined(COMPILER_FEATURES) && ${COMPILER_FEATURES:Mretpoline} != "" && \
|
|
${MK_KERNEL_RETPOLINE} != "no"
|
|
CFLAGS+= -mretpoline
|
|
.endif
|
|
|
|
#
|
|
# Initialize stack variables on function entry
|
|
#
|
|
.if ${MK_INIT_ALL_ZERO} == "yes"
|
|
.if ${COMPILER_FEATURES:Minit-all}
|
|
CFLAGS+= -ftrivial-auto-var-init=zero \
|
|
-enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
|
|
.else
|
|
.warning InitAll (zeros) requested but not support by compiler
|
|
.endif
|
|
.elif ${MK_INIT_ALL_PATTERN} == "yes"
|
|
.if ${COMPILER_FEATURES:Minit-all}
|
|
CFLAGS+= -ftrivial-auto-var-init=pattern
|
|
.else
|
|
.warning InitAll (pattern) requested but not support by compiler
|
|
.endif
|
|
.endif
|
|
|
|
CFLAGS+= ${CWARNFLAGS:M*} ${CWARNFLAGS.${.IMPSRC:T}}
|
|
CFLAGS+= ${CWARNFLAGS.${COMPILER_TYPE}}
|
|
CFLAGS+= ${CFLAGS.${COMPILER_TYPE}} ${CFLAGS.${.IMPSRC:T}}
|
|
|
|
# Tell bmake not to mistake standard targets for things to be searched for
|
|
# or expect to ever be up-to-date.
|
|
PHONY_NOTMAIN = afterdepend afterinstall all beforedepend beforeinstall \
|
|
beforelinking build build-tools buildfiles buildincludes \
|
|
checkdpadd clean cleandepend cleandir cleanobj configure \
|
|
depend distclean distribute exe \
|
|
html includes install installfiles installincludes \
|
|
obj objlink objs objwarn \
|
|
realinstall regress \
|
|
tags whereobj
|
|
|
|
.PHONY: ${PHONY_NOTMAIN}
|
|
.NOTMAIN: ${PHONY_NOTMAIN}
|
|
|
|
CSTD= c99
|
|
|
|
.if ${CSTD} == "k&r"
|
|
CFLAGS+= -traditional
|
|
.elif ${CSTD} == "c89" || ${CSTD} == "c90"
|
|
CFLAGS+= -std=iso9899:1990
|
|
.elif ${CSTD} == "c94" || ${CSTD} == "c95"
|
|
CFLAGS+= -std=iso9899:199409
|
|
.elif ${CSTD} == "c99"
|
|
CFLAGS+= -std=iso9899:1999
|
|
.else # CSTD
|
|
CFLAGS+= -std=${CSTD}
|
|
.endif # CSTD
|
|
|
|
# Please keep this if in sync with bsd.sys.mk
|
|
.if ${LD} != "ld" && (${CC:[1]:H} != ${LD:[1]:H} || ${LD:[1]:T} != "ld")
|
|
# Add -fuse-ld=${LD} if $LD is in a different directory or not called "ld".
|
|
.if ${COMPILER_TYPE} == "clang"
|
|
# Note: Clang does not like relative paths for ld so we map ld.lld -> lld.
|
|
.if ${COMPILER_VERSION} >= 120000
|
|
CCLDFLAGS+= --ld-path=${LD:[1]:S/^ld.//1W}
|
|
.else
|
|
CCLDFLAGS+= -fuse-ld=${LD:[1]:S/^ld.//1W}
|
|
.endif
|
|
.else
|
|
# GCC does not support an absolute path for -fuse-ld so we just print this
|
|
# warning instead and let the user add the required symlinks.
|
|
# However, we can avoid this warning if -B is set appropriately (e.g. for
|
|
# CROSS_TOOLCHAIN=...-gcc).
|
|
.if !(${LD:[1]:T} == "ld" && ${CC:tw:M-B${LD:[1]:H}/})
|
|
.warning LD (${LD}) is not the default linker for ${CC} but -fuse-ld= is not supported
|
|
.endif
|
|
.endif
|
|
.endif
|
|
|
|
# Set target-specific linker emulation name.
|
|
LD_EMULATION_aarch64=aarch64elf
|
|
LD_EMULATION_amd64=elf_x86_64_fbsd
|
|
LD_EMULATION_arm=armelf_fbsd
|
|
LD_EMULATION_armv6=armelf_fbsd
|
|
LD_EMULATION_armv7=armelf_fbsd
|
|
LD_EMULATION_i386=elf_i386_fbsd
|
|
LD_EMULATION_powerpc= elf32ppc_fbsd
|
|
LD_EMULATION_powerpcspe= elf32ppc_fbsd
|
|
LD_EMULATION_powerpc64= elf64ppc_fbsd
|
|
LD_EMULATION_powerpc64le= elf64lppc_fbsd
|
|
LD_EMULATION_riscv64= elf64lriscv
|
|
LD_EMULATION_riscv64sf= elf64lriscv
|
|
LD_EMULATION=${LD_EMULATION_${MACHINE_ARCH}}
|