Original bug ID: 4235
Reporter: djs55
Status: closed (set by @xavierleroy on 2007-05-12T09:24:26Z)
Resolution: fixed
Priority: normal
Severity: crash
Version: 3.09.3
Category: back end (clambda to assembly)
Monitored by: ertai

Bug description

Attached is a small non-recursive program which segfaults when compiled to native code and executed. Program works fine in bytecode, on other architectures and with other ocaml compiler versions. (In particular it doesn't crash on 3.10beta so maybe this is a known fixed bug)

Here's what I get (under CentOS 4.4, ocaml 3.09.3):

$ make
make[1]: Entering directory /bad' ocamlopt -o crash crash.ml File "crash.ml", line 3, characters 6-7: Warning Y: unused variable g. make[1]: Leaving directory /bad'

$ ./crash
Segmentation fault (core dumped)

$ gdb ./crash
GNU gdb Red Hat Linux (6.3.0.0-1.132.EL4rh)
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.
This GDB was configured as "i386-redhat-linux-gnu"...(no debugging symbols found)
Using host libthread_db library "/lib/tls/i686/libthread_db.so.1".

(gdb) run
Starting program: /bad/crash
Reading symbols from shared object read from target memory...(no debugging symbols found)...done.
Loaded system supplied DSO at 0xffffe000
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)

Program received signal SIGSEGV, Segmentation fault.
0x0804aa10 in camlPervasives__failwith_37 ()
(gdb) bt
#0 0x0804aa10 in camlPervasives__failwith_37 ()
Cannot access memory at address 0x1
(gdb)

Additional information

Configuration of machine (actually a chroot) where crash is easily reproduced:

• ocaml 3.09.3
• CentOS 4.4 (ie RH4.4)
• gcc version 3.4.6 20060404 (Red Hat 3.4.6-3)
• Linux ely 2.6.17-11-generic Parse -.x**2. (unary -.) as -.(x**2.). Fix PR#3414 #2 SMP Thu Feb 1 19:52:28 UTC 2007 i686 i686 i386 GNU/Linux

Program works fine on:

• same configuration as above but with ocaml 3.10beta

Program works fine on:

• ocaml 3.09.2
• ubuntu 6.10
• gcc version 4.1.2 20060928 (prerelease) (Ubuntu 4.1.1-13ubuntu5)
• Linux ely 2.6.17-11-generic Parse -.x**2. (unary -.) as -.(x**2.). Fix PR#3414 #2 SMP Thu Feb 1 19:52:28 UTC 2007 i686 GNU/Linux

Program works fine on:

• ocaml 3.09.3
• Mac OS X 10.4 (PowerPC G4)

File attachments

• bad.tgz