Re: [patch] Support LLVM 7

Hi,

On 2018-09-20 10:10:44 +0200, Christoph Berg wrote:
> In the meantime, there's a third architecture where llvm itself
> compiled, but explodes with PG11 - x32:
> 
>   SELECT '' AS tf_12, BOOLTBL1.*, BOOLTBL2.*
>      FROM BOOLTBL1, BOOLTBL2
>      WHERE BOOLTBL2.f1 <> BOOLTBL1.f1;
> ! FATAL:  fatal llvm error: Cannot select: 0x57a7ae60: ch,glue = X86ISD::CALL 0x57a7add0, 0x57a7af38, Register:i32 $edi, RegisterMask:Untyped, 0x57a7add0:1
> !   0x57a7af38: i32 = X86ISD::Wrapper TargetGlobalAddress:i32<void (%struct.TupleTableSlot*)* @deform_0_1> 0
> !     0x57a7aef0: i32 = TargetGlobalAddress<void (%struct.TupleTableSlot*)* @deform_0_1> 0
> !   0x57a7ad88: i32 = Register $edi
> !   0x57a7ae18: Untyped = RegisterMask
> !   0x57a7add0: ch,glue = CopyToReg 0x57a7ad40, Register:i32 $edi, 0x57a7acb0
> !     0x57a7ad88: i32 = Register $edi
> !     0x57a7acb0: i32,ch = CopyFromReg 0x57a367ac, Register:i32 %27
> !       0x57a7ac68: i32 = Register %27
> ! In function: evalexpr_0_0
> ! server closed the connection unexpectedly
> ! 	This probably means the server terminated abnormally
> ! 	before or while processing the request.
> ! connection to server was lost
> 
> https://buildd.debian.org/status/fetch.php?pkg=postgresql-11&arch=x32&ver=11~beta3-2&stamp=1537286634&raw=0

That's pretty clearly an LLVM bug. Could you enable jit_dump_bitcode and
send the bitcode files (I assume there should be something like
<pid>.<generation>.bc and the same with <prefix>.optimized.bc) from the
data directory?

Not that I think x32 is a particularly popular database platform, but
LLVM clearly needs to be fixed independent of PG...

Greetings,

Andres Freund