# $FreeBSD$ # # 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 .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-sse3 -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. # Also explicitly disable Altivec instructions inside the kernel. # .if ${MACHINE_ARCH} == "powerpc" CFLAGS+= -msoft-float -mno-altivec INLINE_LIMIT?= 15000 .endif # # For MIPS we also tell gcc to use floating point emulation # .if ${MACHINE_ARCH} == "mips" CFLAGS+= -msoft-float INLINE_LIMIT?= 8000 .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 # # GCC SSP support. # .if ${MK_SSP} != "no" && ${CC} != "icc" && ${MACHINE_ARCH} != "ia64" && \ ${MACHINE_ARCH} != "arm" && ${MACHINE_ARCH} != "mips" CFLAGS+= -fstack-protector .endif # # Enable CTF conversation on request. # .if defined(WITH_CTF) .undef NO_CTF .endif