Re: [Boost-build] BUMPITTY BUMP: [git] genrating forward headers

Subject: Re: [Boost-build] BUMPITTY BUMP: [git] genrating forward headers
From: Bjørn Roald (bjorn_at_[hidden])
Date: 2013-09-12 15:32:42

On 09/12/2013 05:07 PM, Vladimir Prus wrote:
> On 27.08.2013 23:43, Bjørn Roald wrote:
>
>> I added a new project at libs/Jamfile.v2 to add
>> <implicit-dependency>/boost//headers to all library and test targets.
>> Likewise I added
>> similar requirements to project level in tools/Jamfile.v2 and various
>> Jamroot files I could find.   See:
>> http://lists.boost.org/boost-build/2013/08/26885.php
>> As use of <implicit-dependency>/boost//headers after substitution
>> shall cause any new any effect in SVN layout, I removed the guards I had
>> in earlier patches at project level.  This make things simpler, but it
>> may have side effects we don't want.
>
> Bjørn,
>
> quick question - if we have implicit dependency on headers in
> libs/Jamfile.v2, do we still need such references in Jamfiles for
> individual
> libraries, or those can be eliminated.

My thoughts are they can be eliminated, yes.
I did two steps that are here:

1.
I replaced all old references to headers with implicit_dependency to 
headers to meet the replacement requirement (new syntax).

2.
I added libs/Jamfile.v2 parent projects for all libs to cover the new 
requirement that all targets need to have the implicit_dependency to 
headers.

The #2 step most likely made some of the old references modified in #1 
redundant, but I opted to not clean up not to break things in libs that 
I did not understand.  Also to play safer with regard to SVN layout.  I 
earlier had a modularized layout only guard around the libs/Jamfile.v2 
parent project, but as I removed this, all targets in libs may get the 
implicit dependency in SVN as well and all may be well.

Do you prefer us to clean up more?

>> known issues in modularized layout:
>> ===================================
>>
>> b2 modularized layout issue 1:
>> ------------------------------
>> build in status require build in root first, at a minimum
>> cd $BOOST_ROOT
>> b2 headers
>>
>> but default targets with just b2 seems to work as well.  I think all
>> remaining header links not used by any of the library builds get
>> created at the end.  Maybe stage target depends on headers target or
>> something, I have not checked.  Logically that would make sense.
>
> Which targets on 'status' fail to build headers? I think adding implicit
> dependency to status/Jamfile.v2 shall work.

Steven also was of the opinion that this should work in some earlier 
post.  I also had this working and was surprised it did not at some 
testing just prior to posting this.  So I added the note.  Maybe I had 
mixed up my mental notes here, or there where some finger trouble 
involved.  I will re-check this and see if it is OK.

>> b2 modularized layout issue 2:
>> ------------------------------
>> install require header links to proxy the SVN layout.  The install
>> glob needs update to get the headers from the sources according to
>> Steven.  I have no idea how to do that.
>
> Could you clarify this requirement?

I am not sure I can as it is or will be Stevens words and possibly some 
of my paraphrasing without a clear understanding.  I have spent some 
time trying to understand what this "install glob" that Steven refers to 
is, and how to modify it, but I could not find anything obvious.

Steven says:
Change the header install glob to search the correct include directories

I observe that
b2 install
currently do not work without
b2 headers
first.

Which concur with comments in a resent discussion on the subject quoted 
here:
On 08/23/2013 09:22 PM, Steven Watanabe wrote:> On 08/23/2013 10:27 AM, 
Bjørn Roald wrote:
 >> >On 08/22/2013 04:12 AM, Dave Abrahams wrote:
 >>> >>
 >>>> >>>- Change the header install glob to search the correct include
 >>>> >>>directories
 >>> >>
 >>> >>I have no idea what that means.
 >> >
 >> >I have no really good idea either.  I guess I don't quite 
understand why
 >> >headers cant be installed from the common boost folder as they always
 >> >have, why is a change needed here?.
 >> >
 > It will work, but it requires a two step build.
 > b2 headers
 > b2 install
 >
 > The problem is the order of operations.  The glob
 > that finds the headers to copy runs first, before
 > the links are created.

I could not find the install glob, and thus have no idea of what 
physical code that need to be changed.  So I am stuck.  I can try more 
and harder, but my position is that if this is the only problem left, 
there is no reason to wait for a fix as this is minor issue given the 
improvement for testers in modularized layout.

HTH,
--
Bjørn