Re: A word about C++11 (my humble opinion)

[Tatsuro MATSUOKA]

----- Original Message -----

> From: Julien Bect 
> To: octave-maintainers
> Cc: 
> Date: 2016/6/22, Wed 18:26
> Subject: A word about C++11 (my humble opinion)
> 
> Hello everyone,
> 
> Just wanted to share my disappointment: I just realized that, because of the 
> introduction of C++11 features, the "parallel" package cannot be 
> installed on Ubuntu 12.04 LTS.
> 
> (DISCLAIMER : I don't personally use Ubuntu 12.04 LTS, the problem happened 
> for a colleague that has to use it.)
> 
> The reason is that Ubuntu 12.04 LTS has gcc 4.6.3, which only has a limited 
> support for C++11 features (and apparently not the ones needed by the 
> parallel 
> package, I have bypassed the configure check and can confirm than compilation 
> indeed fails).
> 
> I wouldn't call Ubuntu 12.04 LTS a *very* old release.  It is certainly old 
> in some sense, but Ubuntu 12.04 LTS was release only four years ago, Ubuntu 
> 12.04.5 two years ago, and this distribution hasn't reached its "end of 
> life" date...
> 
> I haven't tested, but the same can be said of Debian Wheezy (7.0), which was 
> released in 2013 and will reach its LTS end of life in May 2018.  Wheezy has 
> gcc 
> 4.7, with a better but still incomplete support of C++11...
> 
> I have seen messages in the mailing list suggesting that more and more C++11 
> feature are starting to be used in Octave itself...
> 
> Does anyone know what is currently the oldest version of gcc that can compile 
> octave stable ? default ?
> 
> Wouldn't it be a reasonable policy to refrain from using C++11 features that 
> are unsupported in versions of gcc that are still "in production" ?
> 
> Just my two cents.
> 
> @++
> Julien
> 
> 
> address@hidden: please don't take it personally, the parallel package is just 
> the 
> one that triggered theses thoughts this morning ;-)


I previously used lubuntu 12.04 and now that PC is not used now.
At that time I have installed gcc-4.8 for Ubuntu 12.04 and used octave build.
(The osmesa was built from source [2].)
I forgotten reason why I decided to use gcc-4.8 instead of gcc-4.6.


At the configure
cd build

CC='gcc-4.8' \
CXX='g++-4.8' \
F77='gfortran-4.8' \
../configure (proper options)

I was anxious that libraries on repo. were built gcc 4.6 but octave were built 
gcc 4.8.
However, I had not met troubles as far as I had used.

Tatsuro


[1] 
http://ubuntuhandbook.org/index.php/2013/08/install-gcc-4-8-via-ppa-in-ubuntu-12-04-13-04/
(Unlike the above instruction I kept gcc 4.6 as default compilier. )

[2] http://wiki.octave.org/OSMesa
(options were slightly arranged for success build)


Tatsuro