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This is so weird. Why doesn't
meta(mod) = mod.__META__
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I think the real issue is probably some corner case in llvm 3.3 and tweaking here and there just happened to make it appears and disappears...
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This might actually be more intermittent than I first thought it was. The startup freezes are frequent enough that from a usability standpoint it might even be release-blocking. Whatever the issue is appears to be deep in the old LLVM JIT's memory management, as far as we've been able to tell so far.
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I did a search for related llvm issues but didn't find anything (not so surprising given we're probably one of the heaviest llvm jit user).
@tkelman Were you able to learn anything from the buffer pointers in llvm? (The retry condition is a pointer comparison IIRC and I'm wondering if we can get a hint from how they are changed in the infinite loop.)
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No not really, I have no clue what to look for. Dunno whether @ihnorton has been able to catch the freeze in gdb like I've done a handful of times. Or you could probably head in and do some work on the dual-boot laptop on @andreasnoack's desk during the week.
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@tkelman
Not being able to see anything obviously wrong from reading the code, the only thing I can suggest is to print the following field of
MCE
in the loop you are stucked inrunOnMachineFunction
before and after callingMCE.startFunction(MF)
as well as before callingMCE.finishFunction(MF)
(so three points in the loop).I don't remember how
gdb
printsC++
classes by default and it might easier to print out the whole class.Watching the address of these might also be helpful but that might generate too much noise before we know more details.
If no one else has better idea, this should at least help us to narrow down the problem.
I'm afraid not the coming weeks. (Weekends works for me though....)