Bug#816000: juce: FTBFS on ppc64el: problems with macro linux

[Fernando Seiti Furusato]

Hello, James.

James Cowgill <jcowgill at debian.org> wrote on 26/02/2016 12:12:06:

> From: James Cowgill <jcowgill at debian.org>
> To: Fernando Seiti Furusato/Brazil/IBM at IBMBR
> Cc: 816000 at bugs.debian.org
> Date: 26/02/2016 12:12
> Subject: Re: Bug#816000: juce: FTBFS on ppc64el: problems with macro 
linux
> 
> Hi,
> 
> On Fri, 2016-02-26 at 09:48 -0500, Fernando Seiti Furusato wrote:
> > Source: juce
> > Version: 4.1.0+repack-2
> > Severity: normal
> > Tags: patch
> > 
> > Dear Maintainer,
> > 
> > The package juce fails to build from source on ppc64el with the
> > following:
> [...]
> > That is due to the preprocessor macro 'linux' being defined on 
ppc64el,
> > with the usage of 2 -std flags: -std=gnu++0x and -std=c++11.
> > 
> > When not using -std=gnu++0x, the package builds on ppc64el.
> > 
> > I know the Makefile is not supposed to be editted, but since we do not
> > regenerate it in the debian build, my patch edits it anyway.
> 
> (Disclaimer: I'm not involved in juce packaging)
> 
> Looking at your patch, can the --std=gnu++0x flag be completely removed
> on all arches? It seems a little fishy to me that a C++ flag is being
> added to CFLAGS and that two C++ standard flags are being used in the
> first place.

I think it could be removed. 
My colleague Gustavo on cc tested a bunch of stuff on ppc64el and
x86_64 because the usage of 2 standards triggers some weird and
inconsistent behaviours. Eg when you switch their order on the 
compiling command line, it defines or not the macro 'linux' on x86_64,
while on ppc64el it defines with 2 standards, no matter the order.

I agree with both of your observations (about c++ flag on CFLAGS and 
using 2 standards).
I do not know why this package does this, it just doesn't feel right, 
but I just assumed the developer did this on purpose.

Anyway, I just did the patch so it would not break on ppc64el.

Regards.
--
Fernando Seiti Furusato
Software Engineer
IBM Brazil - Linux Technology Center