Re: [Caml-list] memory corruption using C stub

[Alexey Egorov <alex.only.d@gmail.com>]

OCaml side is a complex server-side application; unfortunately, it's
closed-source and when I'm trying to minimize OCaml side too it stops
crashing...
I'm using fdopen's opam repository
(https://github.com/fdopen/opam-repository-mingw) with compiler's
versions from 4.03 to 4.05-beta3.


2017-06-11 16:45 GMT+05:00 David Allsopp <dra-news@metastack.com>:
>> On 11 Jun 2017, at 12:38, Alexey Egorov <alex.only.d@gmail.com> wrote:
>>
>> OK, I'm minimized this function as much as possible and it's still
>> crashing - https://pastebin.com/MZ0Qkh9B
>> Now I'm thinking that is compiler's bug on windows...
>
> Are you able to post the OCaml side of your minimised code? Which port of OCaml are you using?
>
>
> David
>
>
>> 2017-06-10 20:33 GMT+05:00 Alexey Egorov <alex.only.d@gmail.com>:
>>> Hello,
>>>
>>> I have an OCaml application with some C code which (I believe) is the
>>> reason of some random crashes.
>>>
>>> Here is the code - https://pastebin.com/FVtLphZu
>>> This function reads file at given offset, divides data into chunks and
>>> compute checksums and compression ratio:
>>>  external compute_data_props
>>>    : string -> int -> int -> int -> (int * int * float) list =
>>> "compute_data_props"
>>>
>>> The problem is, after some calls to this stub, application is crashing
>>> at random places in OCaml code.
>>> I can't figure out what's going wrong, but replacing this stub with
>>> dummy function (which does nothing but returns some predefined list)
>>> eliminates the problem.
>>>
>>> What can we do to debug it? We are using OCaml 4.04.1 and Windows 10,
>>> and there is no other C stubs in our codebase.
>>>
>>> Thanks!
>>
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