Version française
Home     About     Download     Resources     Contact us    

This site is updated infrequently. For up-to-date information, please visit the new OCaml website at

Browse thread
segfault in 3.10.0
[ Home ] [ Index: by date | by threads ]
[ Search: ]

[ Message by date: previous | next ] [ Message in thread: previous | next ] [ Thread: previous | next ]
Date: -- (:)
From: Andres Varon <avaron@g...>
Subject: Re: [Caml-list] segfault in 3.10.0
Hello Everyone,

This is what I have found:

1. The segfault is eliminated if I use position-dependent machine code
(-fno-PIC), which is the main difference that I can see in the
generated code for amd-64 between 3.09.3 and 3.10.0 (-fPIC is the
default now). When using -fno-PIC there was little difference between
the code spilled using -dlinear between the two versions. (I could not
get my program to compile with the branch release310 (3.10.1+dev0
(2007-05-21)) due to a type error that ... ehm ... isn't really a type
error ;-) ).

2. The bug occurs even when I have removed all calls to my C wrappers.
Therefore, I believe this an OCaml issue.

3. The segfault always happens when switching between a pair of
modules that come from the same functor with slightly different

I will continue trying to produce a small example to report to INRIA.

Finally, I have received some very nice suggestions in private and I
would like to thank those who have kindly sent them.



On 8/2/07, Markus Mottl <> wrote:
> On 8/1/07, Andres Varon <> wrote:
> > Has anyone observed sudden segfaults in OCaml 3.10.0 amd-64 under
> > linux?
> I would almost bet it's that one:
> Avoid enabling native stack backtraces (i.e. don't set
> OCAMLRUNPARAM=b=1).  I haven't seen any segfaults yet unless these
> were turned on in which case you may see them often.  Native stack
> backtraces unfortunately seem still broken.

I was hopping it would be the case ,but no, I don't have

> Regards,
> Markus
> --
> Markus Mottl