[fpc-devel] FPC and Windows Phone 8

Vsevolod Alekseyev sevaa at sprynet.com
Thu Mar 13 15:24:13 CET 2014

I've tried; the results are consistent with the interrupt thing. The 
following snippet:

     mov r12, lr
     blx a
     mov lr, r12
     bx lr

     ALIGN 4
     bx lr

Consistently crashes when executed under a debugger, but ran as expected 
10 times in a row when standalone.

Naturally, this means that any kind of *sensible* ARM code would 
pointless. Oh well. At least there are no CPU-level miracles :)

 > You can't prevent interrupts when in Usermode. So even a short 
function will crash sometimes.

 > When you do a non-Thumb function that does not call any other 
function same only can be influenced by an interrupt. So if it crashes 
at all, you know that the interrupt logic of the OS is buggy.

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