On 03/16/17 17:15, Michael Davidson wrote: > Unfortunately, while clang generates a warning about these flags > being unsupported it still exits with a status of 0 so we have > to explicitly disable them instead of just using a cc-option check. > > Signed-off-by: Michael Davidson <md@xxxxxxxxxx> > --- > Makefile | 2 ++ > arch/x86/Makefile | 2 ++ > 2 files changed, 4 insertions(+) > > diff --git a/Makefile b/Makefile > index b21fd0ca2946..5e97e5fc1eea 100644 > --- a/Makefile > +++ b/Makefile > @@ -629,7 +629,9 @@ ARCH_AFLAGS := > ARCH_CFLAGS := > include arch/$(SRCARCH)/Makefile > > +ifneq ($(cc-name),clang) > KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,) > +endif > KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,) > > ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION > diff --git a/arch/x86/Makefile b/arch/x86/Makefile > index 2d449337a360..894a8d18bf97 100644 > --- a/arch/x86/Makefile > +++ b/arch/x86/Makefile > @@ -87,11 +87,13 @@ else > KBUILD_AFLAGS += -m64 > KBUILD_CFLAGS += -m64 > > +ifneq ($(cc-name),clang) > # Align jump targets to 1 byte, not the default 16 bytes: > KBUILD_CFLAGS += -falign-jumps=1 > > # Pack loops tightly as well: > KBUILD_CFLAGS += -falign-loops=1 > +endif > > # Don't autogenerate traditional x87 instructions > KBUILD_CFLAGS += $(call cc-option,-mno-80387) > NAK. Fix your compiler, or use a wrapper script or something. It is absolutely *not* acceptable to disable this since future versions of clang *should* support that. That being said, it might make sense to look for a key pattern like "(un|not )supported" on stderr the try-run macro. Is there really no -Wno- or -Werror= option to turn off this craziness? -hpa
