Re: [PATCH 3/4] hw/arm: Move armv7m_nvic.c to hw/arm/ and always enable it for arm builds

[Thomas Huth]

On 23/09/2019 20.50, Peter Maydell wrote:
> On Mon, 23 Sep 2019 at 19:36, Thomas Huth <address@hidden> wrote:
>>
>> On 23/09/2019 20.27, Peter Maydell wrote:
>>> On Mon, 23 Sep 2019 at 18:54, Thomas Huth <address@hidden> wrote:
>>>> Ok, then what would you suggest to solve the problem that this file has
>>>> always to be linked into the binary? I can't use "obj-y += ..." in
>>>> hw/intc/Makefile.objs since that would mean that the file also gets
>>>> compiled for non-Arm boards. Would you prefer a bunch of stubs instead
>>>> that get used if CONFIG_ARM_V7M is not set?
>>>
>>> I thought obj-y was for only-this-target and obj-common-y was
>>> for all-boards ?
>>
>> Well, obj-y is for the current target that gets compiled. But if you use
>> it in a Makefile that gets used by all targets, the file gets compiled
>> for each target individually.
>>
>> Just try to change "obj-$(CONFIG_ARM_V7M) += armv7m_nvic.o" into
>> "obj-y += armv7m_nvic.o" in hw/int/Makefile.objs, and you'll see it break:
>>
>>   CC      alpha-softmmu/hw/intc/armv7m_nvic.o
>> In file included from include/hw/intc/armv7m_nvic.h:13,
>>                  from hw/intc/armv7m_nvic.c:19:
>> target/arm/cpu.h:1416: error: "FPCR_DZE" redefined [-Werror]
>>  #define FPCR_DZE    (1 << 9)    /* Divide by Zero exception trap enable */
> 
> Sure, so don't define CONFIG_ARM_V7M in a default-config for
> a non-Arm architecture. Then you get the behaviour you want:
> the file is compiled only for the arm targets.

Sigh, the point of this series is that it should also possible to
compile *without* CONFIG_ARM_V7M in default-configs if you want (and
yes, there are people out there who want to be able to compile a
minimalistic QEMU). It's currently not possible to disable this switch.
But ok, if you're not really interested in providing a possibility to
make qemu-system-arm a little bit more flexible in this regard, never
mind, I'll look into other issues instead.

 Thomas