Re: [Xen-devel] Build problems with xen 4.7

[Peng Fan <van.freenix@xxxxxxxxx>]

Hi,

On Fri, May 13, 2016 at 11:23:29AM -0400, Konrad Rzeszutek Wilk wrote:
>On Fri, May 13, 2016 at 03:25:52PM +0100, M A Young wrote:
>> On Fri, 13 May 2016, Jan Beulich wrote:
>> 
>> > >>> On 13.05.16 at 15:49, <konrad.wilk@xxxxxxxxxx> wrote:
>> > > ...
>> > > 
>> > > Still an issue - with 4.7.0-rc1.
>> > 
>> > And I don't recall anyone having contributed a fix/workaround.
>> > 
>> > > If I do:
>> > > 
>> > > $export CFLAGS=" "'
>> > > $make
>> > > 
>> > > I end up with:
>> > > gcc -E -O1 -fno-omit-frame-pointer -m64 -DBUILD_ID -g 
>> > > -fno-strict-aliasing -std=gnu99 
>> > >[...]
>> > > <command-line>:0:0: error: "__OBJECT_FILE__" redefined [-Werror]
>> > > <command-line>:0:0: note: this is the location of the previous definition
>> > > <command-line>:0:0: error: "__OBJECT_LABEL__" redefined [-Werror]
>> > > <command-line>:0:0: note: this is the location of the previous definition
>> > > cc1: all warnings being treated as errors
>> > > Makefile:62: recipe for target 'compat/callback.i' failed

I met similar issue when cross compile xen for ARM64 on X86 PC using yocto poky 
4.9.3
toolchain.

aarch64-poky-linux-gcc -O2 -pipe -g -feliminate-unused-debug-types -O1 
-fno-omit-frame-pointer -DBUILD_ID -g -fno-strict-aliasing -std=gnu99 -Wall 
-Wstrict-prototypes -Wdeclaration-after-statement -Wno-unused-but-set-variable 
-Wno-unused-local-typedefs -O1 -fno-omit-frame-pointer -DBUILD_ID -g 
-fno-strict-aliasing -std=gnu99 -Wall -Wstrict-prototypes 
-Wdeclaration-after-statement -Wno-unused-but-set-variable 
-Wno-unused-local-typedefs -O1 -fno-omit-frame-pointer -DBUILD_ID -g 
-fno-strict-aliasing -std=gnu99 -Wall -Wstrict-prototypes 
-Wdeclaration-after-statement -Wno-unused-but-set-variable 
-Wno-unused-local-typedefs -nostdinc -fno-builtin -fno-common -Werror 
-Wredundant-decls -Wno-pointer-arith -pipe -g -D__XEN__ -include 
/home/Freenix/work/sw-stash/imx8/8qm/xen/xen/xen/include/xen/config.h 
'-D__OBJECT_FILE__="/home/Freenix/work/sw-stash/imx8/8qm/xen/xen/xen/xen"' 
-Wa,--strip-local-absolute -fno-optimize-sibling-calls -fno-omit-frame-pointer 
-MMD -MF /home/Freenix/work/sw-stash/imx8/8qm/xen/xen/xen/.xen.d -mcpu=generic 
-mgeneral-regs-only -DCONFIG_EARLY_PRINTK 
-DEARLY_PRINTK_INC=\"debug-imx8qm.inc\" -DEARLY_PRINTK_BAUD= 
-DEARLY_UART_BASE_ADDRESS=0x5a060000 -DEARLY_UART_REG_SHIFT= 
-fno-optimize-sibling-calls 
-I/home/Freenix/work/sw-stash/imx8/8qm/xen/xen/xen/include -fno-stack-protector 
-fno-exceptions -Wnested-externs -DGCC_HAS_VISIBILITY_ATTRIBUTE -O1 
-fno-omit-frame-pointer -DBUILD_ID -g -fno-strict-aliasing -std=gnu99 -Wall 
-Wstrict-prototypes -Wdeclaration-after-statement -Wno-unused-but-set-variable 
-Wno-unused-local-typedefs -O1 -fno-omit-frame-pointer -DBUILD_ID -g 
-fno-strict-aliasing -std=gnu99 -Wall -Wstrict-prototypes 
-Wdeclaration-after-statement -Wno-unused-but-set-variable 
-Wno-unused-local-typedefs -nostdinc -fno-builtin -fno-common -Werror 
-Wredundant-decls -Wno-pointer-arith -pipe -g -D__XEN__ -include 
/home/Freenix/work/sw-stash/imx8/8qm/xen/xen/xen/include/xen/config.h 
'-D__OBJECT_FILE__="asm-offsets.s"' -Wa,--strip-local-absolute 
-fno-optimize-sibling-calls -fno-omit-frame-pointer -MMD -MF ./.asm-offsets.s.d 
-mcpu=generic -mgeneral-regs-only -DCONFIG_EARLY_PRINTK 
-DEARLY_PRINTK_INC=\"debug-imx8qm.inc\" -DEARLY_PRINTK_BAUD= 
-DEARLY_UART_BASE_ADDRESS=0x5a060000 -DEARLY_UART_REG_SHIFT= 
-I/home/Freenix/work/sw-stash/imx8/8qm/xen/xen/xen/include -fno-stack-protector 
-fno-exceptions -Wnested-externs -DGCC_HAS_VISIBILITY_ATTRIBUTE -S -o 
asm-offsets.s arm64/asm-offsets.c
<command-line>:0:0: error: "__OBJECT_FILE__" redefined [-Werror]
<command-line>:0:0: note: this is the location of the previous definition
cc1: all warnings being treated as errors


>> > 
>> > My previous recommendation stands: Then just don't do this.
>> 
>> I hacked around it for my test builds (eg. see my test build at
>> https://copr.fedorainfracloud.org/coprs/myoung/xentest/build/204111/
>> ) by not setting CFLAGS in the environment, but by instead adding the 
>> recommended Fedora RPM settings into config/StdGNU.mk via a different 
>> environment variable.
>
>ah:
>
>--- xen-4.7.0/config/StdGNU.mk.orig    2016-04-15 22:56:52.191227591 +0100
>+++ xen-4.7.0/config/StdGNU.mk 2016-04-15 23:01:40.978829756 +0100
>@@ -37,6 +37,12 @@
> 
> ifneq ($(debug),y)
> CFLAGS += -O2 -fomit-frame-pointer -fno-tree-coalesce-vars
>+ifeq ($(XEN_TARGET_ARCH),x86_64)
>+#might be cross-compiling so strip out possible x86_32 options
>+CFLAGS += $(shell echo $(CFLAGS_EXTRA) | sed -e 's/-m32//g' -e 
>'s/-march=i686//g' -e 's/-mtune=atom//g')
>+else
>+CFLAGS += $(CFLAGS_EXTRA)
>+endif
> else
> # Less than -O1 produces bad code and large stack frames
> CFLAGS += -O1 -fno-omit-frame-pointer
>
>
>And in the spec file:
>export CFLAGS_EXTRA="$RPM_OPT_FLAGS"
>make %{?_smp_mflags} %{?efi_flags} prefix=/usr dist-xen
>

Does this patch work when cross compile for ARM64?

Thanks,
Peng.

>
>> 
>> Another thing you might need to know if you are building xen on Fedora 24 
>> is that you need to add -fno-tree-coalesce-vars if you are on a gcc-6.0.0 
>> package (it may be fixed in gcc-6.1.1-2.fc24 which has just come out but I 
>> haven't tested it yet).
>> 
>>      Michael Young
>
>_______________________________________________
>Xen-devel mailing list
>Xen-devel@xxxxxxxxxxxxx
>http://lists.xen.org/xen-devel

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel