GHCi on Windows segfaults

GHCi on Windows has had a segfault for while now on x86_64. During the upgrade of GCC in D1123 I noticed that test prog003 was failing with a segfault.

Currently the segfault exist in both versions but on x86 it's particularly easy to trigger.

In my case I can't even start ghci.

$ inplace/bin/GHC-stage2.exe --interactive
GHCi, version 7.11.20151213: http://www.haskell.org/ghc/  :? for help
Segmentation fault/access violation in generated code

The segfault does not seem to happen when linked to the debug rts, and running with +RTS -Ds -RTS doesn't report anything special.

Compiling with devel2 so the rts gets compiled with -g the stack trace is not very useful.

(gdb) run --interactive
Starting program: /home/Tamar/ghc/inplace/bin/ghc-stage2 --interactive
[New Thread 108480.0x1960c]
[New Thread 108480.0x19b2c]
[New Thread 108480.0x19c30]
[New Thread 108480.0x1a0a8]
[New Thread 108480.0x1a93c]
[New Thread 108480.0x13954]
[New Thread 108480.0x14440]
GHCi, version 7.11.20151213: http://www.haskell.org/ghc/  :? for help

Program received signal SIGSEGV, Segmentation fault.
0x06843aa5 in ?? ()
(gdb) bt
#0  0x06843aa5 in ?? ()
#1  0x04b82cfc in ?? ()
#2  0x8d078902 in ?? ()
#3  0xc689fd47 in ?? ()
#4  0xff04c583 in ?? ()
#5  0x83c70065 in ?? ()
#6  0x0000033c in ?? ()
#7  0x00000008 in ?? ()
#8  0x04e9c689 in ?? ()
Backtrace stopped: Cannot access memory at address 0x47c70cc8

And the output of p4

(gdb) p4 0x06843aa5
0x6843ab0:      0x330073
0x6843aac:      0x790073 <c1CgU_info+131>
0x6843aa8:      0x6d005c <c1rsa_info+715>
0x6843aa4:      0x3a0045

Trac metadata

Trac field	Value
Version	7.11
Type	Bug
TypeOfFailure	OtherFailure
Priority	high
Resolution	Unresolved
Component	Runtime System
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	simonmar
Operating system
Architecture