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Date: Tue, 10 Sep 2013 18:46:27 +0200
From: Xavier Leroy <Xavier.Leroy@inria.fr>
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To: oleg@okmij.org
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Subject: Re: [Caml-list] Accelerating compilation

On 10/09/13 04:01, oleg@okmij.org wrote:

> So, the real problem to me is ocamlc using RTLD_NOW flag when loading
> shared library. Removing the flag would make linking faster, and less
> painful.

Sounds reasonable.  I can give it a try later, but if anyone feels
like experimenting, please share your findings.

For the record, the intent of this dynamic loading is to check *at
link-time* that dynamically-loaded stubs provide all the external C
functions needed by the OCaml bytecode program.  (As opposed to
failing when the bytecode program is started.)  In other words, to
detect this problem as early as if one was doing "ocamlc -custom".

Adrian Nader adds:

> That completely breaks for cross-compilation. No matter how hard you
> try, you're going to have troubles loading a PE32 shared library from
> your ELF executable (and even more if you try to load AArch64 on
> MIPS).

Don't worry, it's only for bytecode.  Bytecode executables are already
portable across platforms, so no special cross-compilation support is
needed.  For native code, ocamlopt links C stub libraries statically,
delegating the job to the (cross-)linker.

- Xavier Leroy