[Development] RFD: Removing environment variable support from configure

[Thiago Macieira]

See below for more details.

Summary: if CXXFLAGS is set on the environment when you run configure, the OS X 
build breaks.

This happened because we don't test the building while those flags are set.

I'm proposing we drop even checking them (configure lines 556 to 580).

If you disagree and you want to keep environment variables supported, we'll 
need a volunteer to test and maintain this functionality, on all OSes in which 
the configure script is run. And don't forget the cross-compilation 
permutations.

----------  Forwarded Message  ----------

Subject: Re: [Interest] [OS X] Qt 5.6.0 minimal build configuration (error 
compiling qlatincodec.cpp)
Date: quinta-feira, 17 de março de 2016, 20:48:19 PDT
From: René J. V. Bertin <rjvbertin at gmail.com>
To: interest at qt-project.org

Thiago Macieira wrote:

> The proper way of adding options is to modify the mkspec's qmake.conf file

qmake.conf or .qmake.conf?

>> Checking my build scripts, I can confirm that CFLAGS and CXXFLAGS are set
>> *through the environment*, not by any direct action of mine.
> 
> Yeah, not tested. This is the cause of your problem.

A bit easy, no? I'd say either you simply ignore settings from the 
environment, 
or else you do things correctly. And that would probably mean adding settings 
from the environment to whatever flags you set yourself as I think that's the 
accepted or at least usual way to do it (even CMake does).

Anyway, I see that I had been missing a qmodule.pri edit. For some reason Qt 
5.5.1 built fine with QMAKE_CXXFLAGS="-O3 -march=native -g". After replacing 
that with QMAKE_CXXFLAGS+=etc the build now appears to be happy.

Shouldn't be too hard to generate that file using += instead of a simple = ?

> On quinta-feira, 17 de março de 2016 11:38:58 PDT Thiago Macieira wrote:
>> > - -stdlib=libc++ appear to be missing only from CXXFLAGS in the Makefiles
>> > under qtbase/src/tools
>> 
>> Hmm... those are "bootstrapped" tools. But I can't find anything that
>> overrides  QMAKE_CXXFLAGS.
> 
> Can you confirm that it *is* present in src/corelib/Makefile?

When is that file supposed to be created? I don't have it immediately after 
running configure (and now of course it *will* contain the option that was 
missing).

R.

_______________________________________________
Interest mailing list
Interest at qt-project.org
http://lists.qt-project.org/mailman/listinfo/interest

-----------------------------------------
-- 
Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel Open Source Technology Center