automake vs. GNU make [LWN.net]

automake vs. GNU make

Posted Feb 8, 2008 21:26 UTC (Fri) by nix (subscriber, #2304)
In reply to: automake vs. GNU make by lovelace
Parent article: LCA: Disintermediating distributions

It reduces the complexity, but fundamentally these systems have different 
*runtime* semantics, which can't be entirely hidden. For simple uses 
(DT_NEEDED-style simple symbol lookup of libraries with no undefined 
symbols, and dlopen()/dlsym()/dlclose()-style dynamic loading), libtool 
does a good job. Anything more complex will hit trouble on one system or 
another.

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automake vs. GNU make

Posted Feb 8, 2008 21:46 UTC (Fri) by lovelace (subscriber, #278) [Link]

Ah, now I'm remembering more about what the problems where.

1. Shared libraries and modules are the same on Linux (and lots of other Unices) but are
different on the Mac.  Libtool had a difficult time understanding this.
2. Until fairly recently (Tiger, iirc) shared libraries couldn't be easily dlopened on the
mac, only modules could.

Since KDE makes extensive use of dlopen-ing modules to accomplish things this made things
quite tricky and libtool wasn't really that much help.

So, yeah, quite a different runtime system.  Newer versions of OS X have gotten quite a bit
better on the dlopen-ing front, but they are still fundamentally different.  And, I wouldn't
even try to use libtool to create OS X frameworks....

automake vs. GNU make

Posted Feb 8, 2008 23:18 UTC (Fri) by nix (subscriber, #2304) [Link]

I'd expect MacOS X support for modules to have been OK since

2003-03-20  Peter O'Gorman  <peter@pogma.com>

        * ltmain.in: Always use $echo not echo for consistency.
        Changes for darwin building. Warn if linking against libs linked
        with -module. Use module_cmds if available and building a module,
        move convenience double lib check,

What else is wrong?

And, yes, your point 2 is hard for libltdl to overcome: if you build the 
library as a lib, not a module, you'd have been stuck whatever libtool 
did.