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. 9# 10# XXX FIXME - revert to -fformat-extensions when we've re-added it 11CWARNFLAGS?= -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes \ 12 -Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual \ 13 -Wno-format -ansi 14# 15# The following flags are next up for working on: 16# -W 17# 18# When working on removing warnings from code, the `-Werror' flag should be 19# of material assistance. 20# 21 22# 23# On the i386, do not align the stack to 16-byte boundaries. Otherwise GCC 24# 2.95 adds code to the entry and exit point of every function to align the 25# stack to 16-byte boundaries -- thus wasting approximately 12 bytes of stack 26# per function call. While the 16-byte alignment may benefit micro benchmarks, 27# it is probably an overall loss as it makes the code bigger (less efficient 28# use of code cache tag lines) and uses more stack (less efficient use of data 29# cache tag lines) 30# 31.if ${MACHINE_ARCH} == "i386" 32CFLAGS+= -mpreferred-stack-boundary=2 33.endif 34 35# 36# On the alpha, make sure that we don't use floating-point registers and 37# allow the use of EV56 instructions (only needed for low-level i/o). 38# Also, reserve register t7 to point at per-cpu global variables. 39# 40.if ${MACHINE_ARCH} == "alpha" 41CFLAGS+= -mno-fp-regs -ffixed-8 -Wa,-mev56 42.endif 43 44# 45# For IA-64, we use r13 for the kernel globals pointer and we only use 46# a very small subset of float registers for integer divides. 47# 48.if ${MACHINE_ARCH} == "ia64" 49CFLAGS+= -ffixed-r13 -mfixed-range=f32-f127 50.endif 51 52# 53# GCC 3.0 and above like to do certain optimizations based on the 54# assumption that the program is linked against libc. Stop this. 55# 56CFLAGS+= -ffreestanding 57