freebsd-skq/sys/conf/kern.mk
obrien ae19feef0a Temporarily add 'WITH_GCC3' that removes -Wno-pointer-sign from the
compiler invocation.  This is just to help get over the hump of people
tracking down bugs that may cross the GCC 4.2 upgrade.
It is envisioned that this option goes away after a suitable amount
of time.
2007-05-24 21:53:42 +00:00

100 lines
3.0 KiB
Makefile

# $FreeBSD$
#
# Warning flags for compiling the kernel and components of the kernel.
#
# Note that the newly added -Wcast-qual is responsible for generating
# most of the remaining warnings. Warnings introduced with -Wall will
# also pop up, but are easier to fix.
.if ${CC} == "icc"
#CWARNFLAGS= -w2 # use this if you are terribly bored
CWARNFLAGS=
.else
CWARNFLAGS?= -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes \
-Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual \
${_wundef} ${_Wno_pointer_sign} -fformat-extensions
.if !defined(WITH_GCC3)
_Wno_pointer_sign=-Wno-pointer-sign
.endif
.if !defined(NO_UNDEF)
_wundef= -Wundef
.endif
.endif
#
# The following flags are next up for working on:
# -W
#
# On the i386, do not align the stack to 16-byte boundaries. Otherwise GCC
# 2.95 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 SSE and other SIMD
# operations inside the kernel itself. These operations are exclusively
# reserved for user applications.
#
.if ${MACHINE_ARCH} == "i386" && ${CC} != "icc"
CFLAGS+= -mno-align-long-strings -mpreferred-stack-boundary=2 \
-mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3
INLINE_LIMIT?= 8000
.endif
.if ${MACHINE_ARCH} == "arm"
INLINE_LIMIT?= 8000
.endif
#
# For IA-64, we use r13 for the kernel globals pointer and we only use
# a very small subset of float registers for integer divides.
#
.if ${MACHINE_ARCH} == "ia64"
CFLAGS+= -ffixed-r13 -mfixed-range=f32-f127 -fpic #-mno-sdata
INLINE_LIMIT?= 15000
.endif
#
# For sparc64 we want medlow code model, and we tell gcc to use floating
# point emulation. This avoids using floating point registers for integer
# operations which it has a tendency to do.
#
.if ${MACHINE_ARCH} == "sparc64"
CFLAGS+= -mcmodel=medany -msoft-float
INLINE_LIMIT?= 15000
.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.
#
.if ${MACHINE_ARCH} == "amd64"
CFLAGS+= -mcmodel=kernel -mno-red-zone \
-mfpmath=387 -mno-sse -mno-sse2 -mno-mmx -mno-3dnow \
-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.
#
.if ${MACHINE_ARCH} == "powerpc"
CFLAGS+= -msoft-float
INLINE_LIMIT?= 15000
.endif
#
# GCC 3.0 and above like to do certain optimizations based on the
# assumption that the program is linked against libc. Stop this.
#
.if ${CC} == "icc"
CFLAGS+= -nolib_inline
.else
CFLAGS+= -ffreestanding
.endif
.if ${CC} == "icc"
CFLAGS+= -restrict
.endif