As was already pointed out months ago (see http://lists.xen.org/archives/html/xen-devel/2012-02/msg00826.html), gcc 4.7.x (imo validly) refuses to take both -mcpu=cortex-a15 and -march=armv7-a due to conflicting feature sets causing amibiguity in instruction selection. Since the former implies the latter, just use the former (and drop the -march=). Signed-off-by: Jan Beulich <jbeulich@suse.com> --- a/xen/arch/arm/Rules.mk +++ b/xen/arch/arm/Rules.mk @@ -24,7 +24,7 @@ ifneq ($(call cc-option,$(CC),-fvisibili CFLAGS += -DGCC_HAS_VISIBILITY_ATTRIBUTE endif -CFLAGS += -march=armv7-a -mcpu=cortex-a15 -mfpu=vfpv3 -mfloat-abi=softfp +CFLAGS += -mcpu=cortex-a15 -mfpu=vfpv3 -mfloat-abi=softfp # Require GCC v3.4+ (to avoid issues with alignment constraints in Xen headers) check-$(gcc) = $(call cc-ver-check,CC,0x030400,"Xen requires at least gcc-3.4") _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
On Mon, 2012-06-25 at 11:57 +0100, Jan Beulich wrote:> As was already pointed out months ago (see > http://lists.xen.org/archives/html/xen-devel/2012-02/msg00826.html), > gcc 4.7.x (imo validly) refuses to take both -mcpu=cortex-a15 and > -march=armv7-a due to conflicting feature sets causing amibiguity in > instruction selection. Since the former implies the latter, just use > the former (and drop the -march=). > > Signed-off-by: Jan Beulich <jbeulich@suse.com>Acked-by: Ian Campbell <ian.campbell@citrix.com>> > --- a/xen/arch/arm/Rules.mk > +++ b/xen/arch/arm/Rules.mk > @@ -24,7 +24,7 @@ ifneq ($(call cc-option,$(CC),-fvisibili > CFLAGS += -DGCC_HAS_VISIBILITY_ATTRIBUTE > endif > > -CFLAGS += -march=armv7-a -mcpu=cortex-a15 -mfpu=vfpv3 -mfloat-abi=softfp > +CFLAGS += -mcpu=cortex-a15 -mfpu=vfpv3 -mfloat-abi=softfp > > # Require GCC v3.4+ (to avoid issues with alignment constraints in Xen headers) > check-$(gcc) = $(call cc-ver-check,CC,0x030400,"Xen requires at least gcc-3.4") > > >
On 25/06/12 11:57, Jan Beulich wrote:> As was already pointed out months ago (see > http://lists.xen.org/archives/html/xen-devel/2012-02/msg00826.html), > gcc 4.7.x (imo validly) refuses to take both -mcpu=cortex-a15 and > -march=armv7-a due to conflicting feature sets causing amibiguity in > instruction selection. Since the former implies the latter, just use > the former (and drop the -march=).Given that we currently use the v7-A envelope model rather than a Cortex-A15 I think -march=armv7-a is the correct option. David> > Signed-off-by: Jan Beulich <jbeulich@suse.com> > > --- a/xen/arch/arm/Rules.mk > +++ b/xen/arch/arm/Rules.mk > @@ -24,7 +24,7 @@ ifneq ($(call cc-option,$(CC),-fvisibili > CFLAGS += -DGCC_HAS_VISIBILITY_ATTRIBUTE > endif > > -CFLAGS += -march=armv7-a -mcpu=cortex-a15 -mfpu=vfpv3 -mfloat-abi=softfp > +CFLAGS += -mcpu=cortex-a15 -mfpu=vfpv3 -mfloat-abi=softfp > > # Require GCC v3.4+ (to avoid issues with alignment constraints in Xen headers) > check-$(gcc) = $(call cc-ver-check,CC,0x030400,"Xen requires at least gcc-3.4")
>>> David Vrabel <david.vrabel@citrix.com> 07/03/12 7:09 PM >>> >On 25/06/12 11:57, Jan Beulich wrote: >> As was already pointed out months ago (see >> http://lists.xen.org/archives/html/xen-devel/2012-02/msg00826.html), >> gcc 4.7.x (imo validly) refuses to take both -mcpu=cortex-a15 and >> -march=armv7-a due to conflicting feature sets causing amibiguity in >> instruction selection. Since the former implies the latter, just use >> the former (and drop the -march=). > >Given that we currently use the v7-A envelope model rather than a >Cortex-A15 I think -march=armv7-a is the correct option.Which would mean passing the -mcpu= was wrong from the start. I''ll leave this to the ARM maintainers in any case, the purpose of the change was merely to get the thing to build again. Jan