Re: [Chicken-hackers] [PATCH] Small improvement in Make's handling of variables, and a question about other common variables

[Felix Winkelmann]

From: Christian Kellermann <address@hidden>
Subject: Re: [Chicken-hackers] [PATCH] Small improvement in Make's handling of 
variables, and a question about other common variables
Date: Fri, 13 Jun 2014 10:24:49 +0200

> Felix Winkelmann <address@hidden> writes:
> 
>>> Those two are a constant source of frustration :(  I think we can best
>>> ignore them for now, as they're causing trouble either way: even providing
>>> them by default in the platform Makefiles can be problematic (see Haiku).
>>
>> Please note that these two options are required. I had cases where
>> strict aliasing caused code to fail and -fwrapv disables some
>> questionable optimizations with regard to signed integer overflow. C
>> compilers get more and more aggressive, cutting corners wherever
>> possible by exploiting undefined (but not necessarily unreaasonable)
>> behaviour.
> 
> Well in the particular case of haiku or OpenBSD before that, the
> compiler simply has been too *old* to provide these options. So even if
> the troublesome optimisations are enabled, that way of disabling them
> does not work.

Quite true - we can assume that if there are no options to disable that
behaviour, then the problem probably isn't such an issue for older
compilers.


felix