Re: Lwt installation error

[Thomas Gazagnaire <thomas@xxxxxxxxxxxxxx>]

> You can create "fast" compiler switches without recompiling the compiler in 
> OPAM by

To be complete, the "fast" compiler switches is actually not so fast: it 
recompiles the whole compiler for each alias. The reason is that it is quite 
hard to ensure that the right subtree are exported from one compiler switch to 
another, as some libraries are installed in PREFIX/lib/ocaml/NAME. I have some 
ideas to improve this, but it is not working yet.

So aliases ensure your installations are independent and separate, but you 
don't really gain speed for now on.

--
Thomas

> $ opam switch 4.00.1            # this will build a new compiler
> $ opam switch myxen -a 4.00.1   # this will alias the 4.00.1 compiler
> 
> You can use fast aliases to maintain lightweight chroots of the packages you 
> want, so you can have mirage-unix installed in one, and mirage-xen in the 
> other.
> 
> (the docs on the webpage are almost certainly wrong -- I'm patching Mirari at 
> the moment to simplify the build by outputting Makefiles, and then will 
> update it all after testing).
> 
> Let me know if you need any more help with this...
> 
> -anil
> 
> On 25 Jun 2013, at 14:30, Dimosthenis Pediaditakis 
> <dimosthenis.pediaditakis@xxxxxxxxxxxx> wrote:
> 
>> Hi everyone,
>> has anyone had recently any problems installing 'lwt 2.4.3' against 
>> '4.00.1+mirage-xen' (using opam)?
>> 
>> Thanks,
>> Dimos
>> 
>> 
>> ---------------------------
>>   Error message
>> ---------------------------
>> ocamlfind ocamlc -c -g -I src/core -package unix -package camlp4 -package 
>> bigarray -syntax camlp4o -ppopt syntax/pa_lwt_options.cmo -ppopt 
>> syntax/pa_lwt.cmo -ppopt syntax/pa_lwt_log.cmo -ppopt syntax/pa_optcomp.cmo 
>> -I src/unix -I src/core -o src/unix/lwt_bytes.cmo src/unix/lwt_bytes.ml
>> + ocamlfind ocamlc -c -g -I src/core -package unix -package camlp4 -package 
>> bigarray -syntax camlp4o -ppopt syntax/pa_lwt_options.cmo -ppopt 
>> syntax/pa_lwt.cmo -ppopt syntax/pa_lwt_log.cmo -ppopt syntax/pa_optcomp.cmo 
>> -I src/unix -I src/core -o src/unix/lwt_bytes.cmo src/unix/lwt_bytes.ml
>> File "src/unix/lwt_bytes.ml", line 273, characters 2-17:
>> Error: Unbound value Array1.map_file
>> Command exited with code 2.
>> 
>> ----------------------------------------------------
>>   lines 273-273 src/unix/lwt_bytes.ml
>> ----------------------------------------------------
>> let map_file ~fd ?pos ~shared ?(size=(-1)) () =
>> Array1.map_file fd ?pos char c_layout shared size
>> 
>> ---------------------------
>>  System Info
>> ---------------------------
>> - Ubuntu server 12.10
>> - Kernel 3.5.0-34-generic  x86_64
>> - OCaml version: 4.00.1
>> - Opam version: 1.0.0
>> - Opam repositories:
>> [git]   mirage-dev     git://github.com/mirage/opam-repo-dev
>> [http]     default     http://opam.ocamlpro.com
>> - Installed ocaml packages:
>>     libcryptgps-ocaml-dev,  libcryptokit-ocaml, libcryptokit-ocaml-dev,   
>> libfindlib-ocaml,   libfindlib-ocaml-dev, liblwt-glib-ocaml,  
>> liblwt-glib-ocaml-dev,  liblwt-ocaml, liblwt-ocaml-dev,   liblwt-ocaml-doc, 
>> liblwt-ssl-ocaml, liblwt-ssl-ocaml-dev,    libnethttpd-ocaml-dev, 
>> libobrowser-ocaml-dev,    libocamlnet-ocaml, libocamlnet-ocaml-dev,    
>> libocamlnet-ocaml-doc, libocsigen-ocaml,    libocsigen-ocaml-dev, 
>> libocsigen-ocaml-doc,    libocsigen-xhtml-ocaml-dev, libocsigenserver-ocaml, 
>>    libocsigenserver-ocaml-dev, libpcre-ocaml,    libpcre-ocaml-dev,    
>> libreact-ocaml, libreact-ocaml-dev,    libsqlite3-ocaml,    
>> libsqlite3-ocaml-dev, libssl-ocaml,    libssl-ocaml-dev,    libtext-ocaml, 
>> libtext-ocaml-dev,    libtyxml-ocaml,    libtyxml-ocaml-dev, libzip-ocaml,   
>>  libzip-ocaml-dev,    ocaml,    ocaml-base, ocaml-base-nox,    
>> ocaml-compiler-libs,    ocaml-findlib, ocaml-interp,    ocaml-nox,    
>> ocamlduce,    ocamlduce-base
>> 
>> 
>> 
>> 
> 
>