Re: [gentoo-dev] [RFC] Dealing with global /usr/bin/libtool use vs CC/CXX etc.

[Joshua Kinard <kumba@gentoo.org>]

On 1/10/2021 09:47, Michał Górny wrote:
> On Sun, 2021-01-10 at 14:54 +0100, Fabian Groffen wrote:
>> On 10-01-2021 14:34:13 +0100, Michał Górny wrote:
>>> The vast majority of libtool-based programs use configure script to
>>> generate libtool.  However, a few non-autoconf packages also use libtool
>>> by calling system-installed /usr/bin/libtool.  The problem is that this
>>> libtool hardcodes the values of CC/CXX at its' build time, so unless it
>>> is rebuilt frequently, packages end up using the stale values.
>>> The problem is known since 2005 [1] and hasn't been resolved yet.
>>>
>>> I can think of two ways of solving it:
>>>
>>> 1. We could patch system-installed libtool to respect environment
>>> variables such as CC, CXX, etc.  This will probably require carrying
>>> a (possibly non-trivial) patch forever.  On the bright side, libtool is
>>> not exactly a package seeing frequent releases.  I mean, the current
>>> version is from 2015.
>>>
>>> 2. We could regenerate libtool and force local instance of libtool
>>> in the packages needing it.  The main advantage of this is that it's
>>> a no-brainer.  I could make a quick eclass that does configure a local
>>> instance and prepends it into PATH.
>>>
>>> WDYT?
>>
>> I would prefer option 2, also because on some systems usr/bin/libtool is
>> some entirely different tool than GNU libtool.
>>
>> I remember this being much more of a problem ~15 years ago, so I wonder
>> do we have an easy way of crafting a list of affected packages, such
>> that we can see how big the problem actually is nowadays?  I'm thinking
>> perhaps tinderbox logs or something can reveal /usr/bin/libtool usage
>> somehow.
> 
> I think it might be possible to do something akin USE=-native-symlinks
> that makes libtool not install /usr/bin/libtool, and see what breaks. 
> However, I'm not sure if this executable isn't required for some obscure
> reason anyway.

Second option seems better, and basically just enforces what's been a
standard habit anyways (I at least try to manually rebuild libtool when
changing gcc major versions, but not so much for minor versions).

-- 
Joshua Kinard
Gentoo/MIPS
kumba@gentoo.org
rsa6144/5C63F4E3F5C6C943 2015-04-27
177C 1972 1FB8 F254 BAD0 3E72 5C63 F4E3 F5C6 C943

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