[haskeline] #105: Segfault on getInputLine and getInputChar

[haskeline]

#105: Segfault on getInputLine and getInputChar
---------------------+------------------------------------------------------
Reporter:  syfran    |        Owner:       
    Type:  defect    |       Status:  new  
Priority:  major     |    Milestone:  0.6.2
 Version:            |   Resolution:       
Keywords:  segfault  |  
---------------------+------------------------------------------------------
Old description:

> Haskeline gives a seg fault when getInputLine or getInputChar is called.
>
> {{{
> import System.Console.Haskeline
> main = runInputT defaultSettings $ getInputLine "$$" >> outputStrLn
> "Hello World" :: IO ()
> }}}
>
> This just outputs "Segmentation Fault" when compiled and run (or just
> quits if run with runghc)
>
> On the other hand,
> {{{
> import System.Console.Haskeline
> main= runInputT defaultSettings $ outputStrLn "Hello World" :: IO ()
> }}}
> will output "Hello World" as expected.
>
> System Info--
>   OS: Gentoo Linux
>   Arch: amd64
>   ghc version: 6.10.4
>   haskeline version: 0.6.2.2
>
> If it helps heres the result of gdb where on the above example:
> {{{
>  gdb ./Tests
> GNU gdb (Gentoo 7.1 p1) 7.1
> Copyright (C) 2010 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later
> <http://gnu.org/licenses/gpl.html>
> This is free software: you are free to change and redistribute it.
> There is NO WARRANTY, to the extent permitted by law.  Type "show
> copying"
> and "show warranty" for details.
> This GDB was configured as "x86_64-pc-linux-gnu".
> For bug reporting instructions, please see:
> <http://bugs.gentoo.org/>...
> Reading symbols from /home/syfran/haskelineTests/Tests...(no debugging
> symbols found)...done.
> (gdb) run
> Starting program: /home/syfran/haskelineTests/Tests
> [Thread debugging using libthread_db enabled]
>
> Program received signal SIGSEGV, Segmentation fault.
> 0x0000000000535362 in base_ForeignziCziString_zdwa_info ()
> (gdb) where
> #0  0x0000000000535362 in base_ForeignziCziString_zdwa_info ()
> #1  0x0000000000000000 in ?? ()
> (gdb)
> }}}
>
> Let me know if you need anything else.

New description:

 Haskeline gives a seg fault when getInputLine or getInputChar is called.

 {{{
 import System.Console.Haskeline
 main = runInputT defaultSettings $ getInputLine "$$" >> outputStrLn "Hello
 World" :: IO ()
 }}}

 This just outputs "Segmentation Fault" when compiled and run (or just
 quits if run with runghc)

 On the other hand,
 {{{
 import System.Console.Haskeline
 main= runInputT defaultSettings $ outputStrLn "Hello World" :: IO ()
 }}}
 will output "Hello World" as expected.

 System Info--

   OS: Gentoo Linux

   Arch: amd64

   ghc version: 6.10.4

   haskeline version: 0.6.2.2

 If it helps heres the result of gdb where on the above example:
 {{{
  gdb ./Tests
 GNU gdb (Gentoo 7.1 p1) 7.1
 Copyright (C) 2010 Free Software Foundation, Inc.
 License GPLv3+: GNU GPL version 3 or later
 <http://gnu.org/licenses/gpl.html>
 This is free software: you are free to change and redistribute it.
 There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
 and "show warranty" for details.
 This GDB was configured as "x86_64-pc-linux-gnu".
 For bug reporting instructions, please see:
 <http://bugs.gentoo.org/>...
 Reading symbols from /home/syfran/haskelineTests/Tests...(no debugging
 symbols found)...done.
 (gdb) run
 Starting program: /home/syfran/haskelineTests/Tests
 [Thread debugging using libthread_db enabled]

 Program received signal SIGSEGV, Segmentation fault.
 0x0000000000535362 in base_ForeignziCziString_zdwa_info ()
 (gdb) where
 #0  0x0000000000535362 in base_ForeignziCziString_zdwa_info ()
 #1  0x0000000000000000 in ?? ()
 (gdb)
 }}}

 Let me know if you need anything else.

Comment (by syfran):

 Both methods cause the program to work as expected (just out of
 curiousity, how does this change how the program functions?)

 Not sure if it still helps still but the gdb disassemble of the segfault
 shows

 {{{
 => 0x00000000006adea1 <+33>:    movsbq (%r14),%rax
 }}}
 with r14 containing 0

 being the segfault line (after the function has been called ~21 times)

 I could post the whole disassemble, if you need it.

 Thanks a lot for helping out here, not being able to use ghci getting to
 be a pain.

-- 
Ticket URL: <http://trac.haskell.org/haskeline/ticket/105#comment:3>
haskeline <http://example.org/>
My example project