Unable to compile IcedTea with CACAO under Fedora 17

[Andrew Haley]

On 12/18/2012 06:25 PM, Andrew Haley wrote:
> On 12/18/2012 06:02 PM, Greg Johnson wrote:
>>>> No, they're using the same VM.  The problem is that Raspberry Pi
>>>> doesn't support the Thumb2 instruction set, and the ARM JIT in OpenJDK
>>>> needs it.  I've been hoping that some day a brave soul will come along
>>>> and convert the Thumb2 JIT to generate ARM code instead of Thumb2
>>>> code, but there haven't been any takers.
>>
>> Under Debian, I have this:
>> # java -version
>> java version "1.6.0_18"
>> OpenJDK Runtime Environment (IcedTea6 1.8.13) (6b18-1.8.13-0+squeeze1)
>> OpenJDK Zero VM (build 14.0-b16, mixed mode)
>>
>>
>> Under Fedora, I have this:
>> # java -version
>> java version "1.7.0_b147-icedtea"
>> OpenJDK Runtime Environment (fedora-2.1.fc17.6-arm)
>> OpenJDK Zero VM (build 22.0-b10, interpreted mode)
>>
>>
>> Both are using Zero VM, but with different modes. Then I received
>> this explanation from the Raspberry Pi forums:
>> --------------------------------------
> 
>> The main reason why you see a magnitude difference in the Debian vs
>> Fedora results really boils down to that there exist two variants of
>> Zero.
>>
>> In Fedora you have installed OpenJDK Zero VM (build 22.0-b10,
>> interpreted mode) This is using the C++ interpreter only.
> 
> Ahhh, okay.  All is now clear.  One is Java 7, the other is Java 6.
> 
> The problem is that the ARM assembler port isn't working on Java 7.
> It's nothing to do with Fedora versus Debian: it's just that Debian
> has an old version of OpenJDK.

Incidentally, this does mean that the easiest way to get to where you
want to be in the short term is just to build IcedTea 6.

Andrew.