[GHC] #10080: Recusive IO actions crash with segmentation fault

11 Feb 2015


      #10080: Recusive IO actions crash with segmentation fault
-------------------------------------+-------------------------------------
              Reporter:  nakal       |             Owner:
                  Type:  bug         |            Status:  new
              Priority:  normal      |         Milestone:
             Component:  Compiler    |           Version:  7.8.3
              Keywords:              |  Operating System:  FreeBSD
          Architecture:  x86_64      |   Type of failure:  Runtime crash
  (amd64)                            |        Blocked By:
             Test Case:              |   Related Tickets:
              Blocking:              |
Differential Revisions:              |
-------------------------------------+-------------------------------------
 I am learning Haskell and wrote a program that writes some strings to
 stdout infinitely by recursing in an IO action. It seems such a simple
 construct crashes on FreeBSD when Ctrl+C is pressed to interrupt it.

 I have been able to reduce it to a simple case like this:

 {{{#!hs
 main = do
         putStrLn "hello world"
         main
 }}}

 I compiled it with
 {{{
 ghc --make hello.hs
 }}}

 Then pressed Ctrl+C and immediately got:
 {{{
 [...]
 hello world
 hello world
 hello world
 hello world
 ^CSegmentation fault (core dumped)
 }}}

 Here is the backtrace of the crash:

 {{{
 (gdb) bt
 #0  0x000000000047cdd7 in generic_handler ()
 #1  0x000000080147c467 in swapcontext () from /lib/libthr.so.3
 #2  0x000000080147c062 in sigaction () from /lib/libthr.so.3
 #3  <signal handler called>
 #4  0x00000008017d7b7a in select () from /lib/libc.so.7
 #5  0x0000000801479b32 in select () from /lib/libthr.so.3
 #6  0x000000000043cb13 in fdReady ()
 #7  0x000000000044751c in base_GHCziIOziFD_zdwa3_info ()
 #8  0x0000000000000000 in ?? ()
 }}}

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10080
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