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[Michael Casadevall <810402@xxxxxxxxxxxxxxxxxx>]

So digging into this problem, I can confirm that reverting binutils
resolves the build failure, so we're looking at a definate regression in
binutils. Looking at gdb and the source, the problem comes during
ocaml's internal initialization which is a bunch hand written ASM.

During startup, the application branches into caml_start_program, and
segfaults while trying to load the address of caml_program into r12:


        .globl caml_start_program
caml_start_program:
        ldr     r12, .Lcaml_program

/* Code shared with caml_callback* */
/* Address of Caml code to call is in r12 */
/* Arguments to the Caml code are in r0...r3 */


and caml_program is in the global reference table at the botton:


.Lcaml_program:                 .word caml_program

caml_program appears to be the "main" function of the compiled OCaml
application, as its defined in every compiled ocaml binary I examined.
For some reason, caml_program is pointing to an invalid address so when
the process tries to load, it goes boom.

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https://bugs.launchpad.net/bugs/810402

Title:
  all native ocaml programs segfault on armel

Status in Linaro Binutils:
  New
Status in “binutils” package in Ubuntu:
  Confirmed
Status in “ocaml” package in Ubuntu:
  Confirmed
Status in “binutils” source package in Oneiric:
  Confirmed
Status in “ocaml” source package in Oneiric:
  Confirmed

Bug description:
  Starting from version 2.21.52.20110606-1ubuntu1 (in oneiric), all
  programs produced by ocamlopt segfault on Ubuntu/armel. The problem
  disappears after downgrading binutils to 2.21.51.20110421-6ubuntu1.

  Steps to reproduce: echo > empty.ml && ocamlopt empty.ml && ./a.out

  Using the "-S" option of ocamlopt might be useful, to have a look at
  the generated assembly code, but I don't know what to look for... I
  hope someone more familiar with binutils code can help.

  I found that while investigating the recent build failures of ocaml
  stuff or armel. Everything works find in the armel port of Debian.

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