1# $FreeBSD$ 2 3# 4# Warning flags for compiling the kernel and components of the kernel. 5# 6# Note that the newly added -Wcast-qual is responsible for generating 7# most of the remaining warnings. Warnings introduced with -Wall will 8# also pop up, but are easier to fix. 9CWARNFLAGS?= -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes \ 10 -Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual \ 11 -Wundef -Wno-pointer-sign -fformat-extensions \ 12 -Wmissing-include-dirs 13# 14# The following flags are next up for working on: 15# -Wextra 16 17# 18# On i386, do not align the stack to 16-byte boundaries. Otherwise GCC 2.95 19# and above adds code to the entry and exit point of every function to align the 20# stack to 16-byte boundaries -- thus wasting approximately 12 bytes of stack 21# per function call. While the 16-byte alignment may benefit micro benchmarks, 22# it is probably an overall loss as it makes the code bigger (less efficient 23# use of code cache tag lines) and uses more stack (less efficient use of data 24# cache tag lines). Explicitly prohibit the use of FPU, SSE and other SIMD 25# operations inside the kernel itself. These operations are exclusively 26# reserved for user applications. 27# 28.if ${MACHINE_CPUARCH} == "i386" 29.if ${CC:T:Mclang} != "clang" 30CFLAGS+= -mno-align-long-strings -mpreferred-stack-boundary=2 31.endif 32CFLAGS+= -mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 -msoft-float 33INLINE_LIMIT?= 8000 34.endif 35 36.if ${MACHINE_CPUARCH} == "arm" 37INLINE_LIMIT?= 8000 38.endif 39 40# 41# For IA-64, we use r13 for the kernel globals pointer and we only use 42# a very small subset of float registers for integer divides. 43# 44.if ${MACHINE_CPUARCH} == "ia64" 45CFLAGS+= -ffixed-r13 -mfixed-range=f32-f127 -fpic #-mno-sdata 46INLINE_LIMIT?= 15000 47.endif 48 49# 50# For sparc64 we want medlow code model, and we tell gcc to use floating 51# point emulation. This avoids using floating point registers for integer 52# operations which it has a tendency to do. 53# 54.if ${MACHINE_CPUARCH} == "sparc64" 55CFLAGS+= -mcmodel=medany -msoft-float 56INLINE_LIMIT?= 15000 57.endif 58 59# 60# For AMD64, we explicitly prohibit the use of FPU, SSE and other SIMD 61# operations inside the kernel itself. These operations are exclusively 62# reserved for user applications. 63# 64.if ${MACHINE_CPUARCH} == "amd64" 65CFLAGS+= -mcmodel=kernel -mno-red-zone \ 66 -mfpmath=387 -mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 \ 67 -msoft-float -fno-asynchronous-unwind-tables 68INLINE_LIMIT?= 8000 69.endif 70 71# 72# For PowerPC we tell gcc to use floating point emulation. This avoids using 73# floating point registers for integer operations which it has a tendency to do. 74# Also explicitly disable Altivec instructions inside the kernel. 75# 76.if ${MACHINE_CPUARCH} == "powerpc" 77CFLAGS+= -msoft-float -mno-altivec 78INLINE_LIMIT?= 15000 79.endif 80 81# 82# Use dot symbols on powerpc64 to make ddb happy 83# 84.if ${MACHINE_ARCH} == "powerpc64" 85CFLAGS+= -mcall-aixdesc 86.endif 87 88# 89# For MIPS we also tell gcc to use floating point emulation 90# 91.if ${MACHINE_CPUARCH} == "mips" 92CFLAGS+= -msoft-float 93INLINE_LIMIT?= 8000 94.endif 95 96# 97# GCC 3.0 and above like to do certain optimizations based on the 98# assumption that the program is linked against libc. Stop this. 99# 100CFLAGS+= -ffreestanding 101 102# 103# GCC SSP support 104# 105.if ${MK_SSP} != "no" && ${MACHINE_CPUARCH} != "ia64" && \ 106 ${MACHINE_CPUARCH} != "arm" && ${MACHINE_CPUARCH} != "mips" 107CFLAGS+= -fstack-protector 108.endif 109 110# 111# Enable CTF conversation on request 112# 113.if defined(WITH_CTF) 114.undef NO_CTF 115.endif 116