PIC, alignment problems with libcrypt on armv7

Jussi Kivilinna jussi.kivilinna at iki.fi
Thu Jun 30 23:38:55 CEST 2016


On 30.06.2016 10:43, Jussi Kivilinna wrote:

>> The second problem showed up as a bus error running tests/basic.
>> The problem is that ldm/stm don't deal with unaligned accesses even
>> on armv7 (see http://www.heyrick.co.uk/armwiki/Unaligned_data_access).
>> My workaround is to undef the gcc-defined feature symbol, but a better
>> fix would be to strip out the conditional guards, since the alignment
>> adjustments are needed on all versions.
> 
> I have made wrong assumption about unaligned accesses with ldm/stm.
> I'll make the needed changes and add proper unaligned buffer test cases
> so that these will be caught in future.
> 

Appears that there is proper tests for unaligned buffers. However those
tests did not fail for me, since on Linux unaligned ldm/stm exception
is caught and handled by kernel. 

-Jussi




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