Hey, I am still investigating the segfaults of the exectuable produced by ghc to arm-linux-androideabi cross compiler. I need help. Can someone tell me if my conclusions are correct? The crash happens here: Dump of assembler code for function stg_returnToStackTop: 0x003f059c <+0>: push {r4, lr} 0x003f05a0 <+4>: sub sp, sp, #16 0x003f05a4 <+8>: ldr r1, [r0, #140] ; 0x8c => 0x003f05a8 <+12>: ldr r12, [r1, #12] 0x003f05ac <+16>: ldr r1, [r12, #12] 0x003f05b0 <+20>: mov r2, #0 Since it is in the begining of stg_returnToStackTop, it has to be LOAD_THREAD_STATE(); I believe the code for this is produced by loadThreadState: loadThreadState dflags tso stack = do catAGraphs [ -- tso = CurrentTSO; mkAssign (CmmLocal tso) stgCurrentTSO, -- stack = tso->stackobj; mkAssign (CmmLocal stack) (CmmLoad (cmmOffset dflags (CmmReg (CmmLocal tso)) (tso_stackobj dflags)) (bWord dflags)), (...) So I believe the instruction are mapped like this: ldr r1, [r0, #140] <-> tso = CurrentTSO ldr r12, [r1, #12] <-> stack = tso->stackobj If that is true, the loaded tso pointer ([r0, #140]) must be wrong. When I look at the backtrace at the moment of crash: #0 0x003f0588 in stg_returnToStackTop () #1 0x003c2e74 in schedule (initialCapability=0x3f057c, task=0x52f350) at rts/Schedule.c:463 #2 0x003c2e74 in schedule (initialCapability=0x52f340, task=0x400a42f0) at rts/Schedule.c:463 #3 0x003c4cb0 in scheduleWaitThread (tso=0x401033c0, ret=0x0, pcap=0xbe843b6c) at rts/Schedule.c:2351 There is a "tso" value passed to scheduleWaitThread (tso=0x401033c0). Should be this is the same address, form where the tso is loaded in the instruction: ldr r1, [r0, #140] <-> tso = CurrentTSO ? If so, the value in r0 is way of. info register r0 0x3f057c 4130172 r1 0xe24dd010 -498216944 Are my conclusions so far correct, and I have to find out why r0 is having the wrong value? Thanks! Nathan