Re: [Boost-build] Very slow Visual Studio 2012 builds

Subject: Re: [Boost-build] Very slow Visual Studio 2012 builds
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2013-11-04 16:49:59

AMDG

On 11/04/2013 01:01 PM, Nogradi, Chris wrote:
> 
> Well I had originally implemented this wrong as well and Steve corrected me.  I think you REALLY want to create a batch file with the environment variables set to deal with command line size limits and make it a dependency of all the compile/assembly/link/... targets. This also makes incrementals a bit faster since the batch file is created once and then used on every subsequent build. I originally did this but have not had time to fix it to do what Steve suggested (also it is going to take me a while to figure it out since I am not an expert):
> 

The command line limits may not matter.
Boost.Build writes the whole command
out into a temporary batch script anyway,
unless you explicitly set JAMSHELL to "%".

> ...
> # Append setup options to the setup name and add the final setup
>                 # prefix & suffix.
>                 setup-options ?= "" ;
>                 setup-$(c) = [ create-setup $(setup-$(c)) : $(setup-prefix) : $(setup-options) : setup-$(c) ] ;
>                 setup-$(c) = $(setup-prefix)$(setup-$(c):J=" ")$(setup-suffix) ;
> ...
> 
> local rule create-setup ( setup : setup-prefix * : setup-options * : file )
> {
>     import regex ;
>     import set ;
>     vars ?= [ SHELL "set" ] ;
>     original-vars ?= [ regex.split "$(vars)" "\\\n" ] ;
>     setup = $(setup-prefix)$(setup:J=" ")" "$(setup-options:J=" ")" >nul && set" ;
>     local new-vars = [ SHELL "$(setup)" ] ;
>     new-vars = [ regex.split "$(new-vars)" "\\\n" ] ;
>     local diff = [ set.difference $(new-vars) : $(original-vars) ] ;
>     local path = [ path.join bin [ property.as-path [ feature.split $(conditions) ] ] ] ;
>     common.MkDir $(path) ;
>     local msvc-setup = [ path.native [ path.join $(path) $(file).bat ] ] ;
>     local target = <setup-file>$(msvc-setup) ;
>     DEPENDS $(target) : $(path) ;
>     FILE_CONTENTS on $(target) = "@echo off"$(.nl)set" "$(diff:J="$(.nl)set ") ;
>     ALWAYS $(target) ;
>     msvc.write-setup $(target) ;
>     .log-fd ?= [ FILE_OPEN [ path.join bin msvc.log ] : "w" ] ;
>     UPDATE_NOW $(target) : $(.log-fd) : ignore-minus-n ;
>     return $(msvc-setup) ;
> }
> 
> actions write-setup
> {
>     @($(STDOUT):E=$(FILE_CONTENTS:J=)) > "$(<)"
> }
> 

write-setup can be spelled:

import print ;
print.output $(target) ;
print.text ... ;

(b2 --help print for more details)

> This solution kind of works except the destination dir is hard coded to bin and if the real bin dir is bin also there is a directory creation conflict.  I think Steve's batch file target as a dependency of all targets is a much better solution. I was going to get to it this week but I am not opposed to you doing it for me ;)
> 

boostbook.jam creates a file called boostbook_config.xml.
You can use its implementation for inspiration.
(FWIW, common.MkDir is intended to be called many
times with the same paths.  It shouldn't create a
conflict)

In Christ,
Steven Watanabe