Re: [PATCH v1] target/m68k: fix gdb for m68xxx

[Laurent Vivier]

Le 20/04/2020 à 21:08, KONRAD Frederic a écrit :
> 
> 
> Le 4/20/20 à 5:46 PM, Laurent Vivier a écrit :
>> Le 20/04/2020 à 16:01, address@hidden a écrit :
>>> From: KONRAD Frederic <address@hidden>
>>>
>>> Currently "cf-core.xml" is sent to GDB when using any m68k flavor. 
>>> Thing is
>>> it uses the "org.gnu.gdb.coldfire.core" feature name and gdb 8.3 then
>>> expects
>>> a coldfire FPU instead of the default m68881 FPU.
>>
>>
>> I checked in gdb sources and there is no cf definition.
>>
>> Moreover if I change only the cf to m68k in QEMU it seems to work in
>> both cases:
>>
>> diff --git a/gdb-xml/cf-core.xml b/gdb-xml/cf-core.xml
>> index b90af3042c..5b092d26de 100644
>> --- a/gdb-xml/cf-core.xml
>> +++ b/gdb-xml/cf-core.xml
>> @@ -5,7 +5,7 @@
>>        are permitted in any medium without royalty provided the copyright
>>        notice and this notice are preserved.  -->
>>   <!DOCTYPE feature SYSTEM "gdb-target.dtd">
>> -<feature name="org.gnu.gdb.coldfire.core">
>> +<feature name="org.gnu.gdb.m68k.core">
>>     <reg name="d0" bitsize="32"/>
>>     <reg name="d1" bitsize="32"/>
>>     <reg name="d2" bitsize="32"/>
> 
> Doesn't that break gdb with coldfire?

No, it seems to work, but I didn't test this really carefully.

So perhaps we can only change the feature name in the two existing xml
files and it will work for all the cases? (and renaming cf-core.xml to
m68k-core.xml).

The core files are the same for cf and m68k, so according to the sample
code you show, if it finds "org.gnu.gdb.m68k.core" if will use for both.

I think the only bug we have is the feature name is not good in
m68k-fp.xml, and fixing that should be enough.

Thanks,
Laurent