[mythtv-users] Re: Undefined symbol error when running CVS

[Shawn]

On Thu, 2004-11-11 at 17:53 -0800, Jarod Wilson wrote:
> Okay, fine, I'll jump back in to this one.

Okay.

> Yesterday night, you said:
> ---
> Likely a library it's linking to has been compiled with a compiler not
> ABI compatible with what myth was compiled with (2.96 v 3.X?), or some
> psycho-babble sounding like that. (The "_ZNBlahHorkBeeble" bullshit is a
> clue)
> ---
> 
> This would appear to be untrue.

Notice I said likely, and not absolutely. If you're going to argue over
what's generally more likely to cause binary incompatibility I'm not
biting on that one.

> You also said:
> ---
> Try looking at all the libraries myth links to (ldd), and recompiling
> those libraries with the same gcc (or g++ as it were).
> ---
> 
> Recompiling those libraries isn't the right answer. Removing the ones 
> installed by the rpms was, since they took precedence at link time after 
> everything from CVS was compiled and installed.

Okay, but one would see libmyth*.so* in the wrong place, and hopefully
*bing* the light goes on before recompiling, but yeah, I was wrong on
how precisely to fix the issue.

> Then earlier today, you said:
> ---
> Here's the deal: If the myth program compile-time links successfully but
> cannot run-time link successfully, it's binary incompatible, most likely
> due to compiler or binutils. You may have written a document, but I'm
> fairly certain you're wrong. When libraries are incompatible in such a
> way as you say, one of a number of things happen:
>      1. The program fails to compile-time link due to trying to pass the
>         wrong number or type of arguments to a given function
>      2. The program fails to compile-time link due to trying to pass
>         seemingly compatibly structured data (type, number of args, etc)
>         but the data itself makes the function barf.
>      3. The function returns incompatible type and compile-time link
>         fails
>      4. The function returns seemingly compatibly structured data (type,
>         etc) but the data itself makes the calling code barf.
> In other words, it probably won't compile, but if it does, it's image
> will likely at least load into memory after /lib/ld-linux.so.2 is done,
> and at some point it will probably segfault.
> ---
> 
> This is also wrong, per the stuff I quoted from Isaac above. However, I 
> actually wasn't quite correct either in my statement that the problem was CVS 
> Myth being built against 0.16 release libs, since the build is against the 
> libs in the source dir (see, I can admit when I'm wrong). The problem was 
> running the CVS-installed frontend with the rpm-installed libs present, 
> taking precedence over the CVS-installed libs at run-time linking.

My scenario (points 1-4) only illustrates how your statement that myth
was built against older libs is false and reasons why this is fact, and
taken as such is NOT wrong, and Isaac's post supports it.

> > Why the hell have I been pounced on for trying to fucking help?
> 
> Trying to help is a good thing, and some of us (namely, me, I see nothing 
> wrong with what Isaac or Axel said) probably shouldn't have been quite so 
> dismissive. But life isn't all warm fuzzies. I think you've been pounced on 
> more for continuing to insist that you're not wrong, when the correct 
> solution has already been put forward, with quite a bit of evidence as to why 
> you weren't correct from a number of folks who have been involved with this 
> project for quite some time. And once again, swearing has a way of making a 
> technical argument look less intelligent, regardless of its actual merits.

In fact I've been wrong when I say "likely" or "probably", but your
absolute statements, and subsequent defenses of said statements have
been insulting, technically incorrect, and dismissive as you say.

That's going to piss some people off pretty well when they were only
exploring possible solutions in attempts to help.

> > Second, I have yet to hear where I steered someone wrong.
> 
> See above. And chill out.

Yeah, I'm looking. Nope, nothing to see there, and look who's talking.
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