[AMBER-Developers] gcc 4.1.2

From: Jason Swails <jason.swails.gmail.com>
Date: Tue, 10 Mar 2015 22:53:03 -0400

Hello everyone,

Due to my recent work/attempts to get Amber working with GCC 4.1.2 again, I wanted to raise the question of whether or not we should drop support for this particular compiler altogether. I’m personally in favor of dropping support for the following reasons:

- It is a limiting compiler; 3D-RISM, mdgx, part of the sander API, and the PBSA FFT solver do not work because fftw-3 uses features not supported by that version of GCC.
- GCC 4.1.2 was released over 8 years ago, and only RHEL 5 (superseded by RHEL 6/7, released in 2007, and nearing end-of-life) is still in use (?) and ships with this version of GCC; even it has GCC 4.4 in its yum repositories.
- No developers use GCC 4.1.2 regularly (or they would have found the build failing for the past 5 months)
- Maintaining GCC 4.1.2 compatibility will only get harder, and the hacks thrown in to cut out the pieces that don’t work with it make the code more complex

In my opinion, the biggest strike against supporting GCC 4.1.2 is that since no developer uses it, features and code that break compatibility likely won’t be found until months after the code was introduced, and nobody really knows which features are supported and which ones aren’t.

At some point compatibility will simply have to be dropped. Should it be now, when the code will be a bit easier to simplify? Or do we wait until the workarounds become too hard? (And perhaps most importantly -- does anybody still rely on this for their work?)


Jason M. Swails
Rutgers University
Postdoctoral Researcher
AMBER-Developers mailing list
Received on Tue Mar 10 2015 - 20:00:02 PDT
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