Gentoo Archives: gentoo-portage-dev

From: tvali <qtvali@×××××.com>
To: gentoo-portage-dev@l.g.o
Subject: Re: [gentoo-portage-dev] DB and binary dependency
Date: Thu, 16 Mar 2006 14:19:09
In Reply to: Re: [gentoo-portage-dev] DB and binary dependency by Paul de Vrieze
1 > To make this things worse, the above example assumes that within a slot,
2 > the libraries are binary compatible. There are examples of libraries that
3 > are not. And what about a library whose interface is dependent on a third
4 > library: B uses A, C uses B, but B exports A. So B is dependent on A, and
5 > the binary package of C must record that B was compiled with A.
6 >
7 > In short, welcome to binary package hell. This is the reason that binary
8 > distributions must use versions. Even debian. It is just very very hard
9 > to fix these kinds of indirect dependencies.
11 I think that there are many reasons, why such kind of important thing
12 should not be automatically generated. Starting from the fact that one
13 thing is dependency in binary, another thing is knowledge if this
14 combination actually works, has no bugs, should not be masked.
16 Anyway, if such binary dependancyes should ever be used, then it would
17 be best to:
18 1. register version number of interfaces
19 2. register interface groups
21 I mean:
22 If some lib supports commands turnon() and turnoff(), but one version
23 supports additionally command int checkifturnedon() and another
24 supports char checkifturnedon(), then there should be:
25 * Interface group, which states only that there are turnon and turnoff
26 functions -- as many apps use only most standard and minimalistic set
27 of commands from one lib, there is no need to know if some advanced
28 features are 0.9.80 or 0.9.64 compatible.
29 * Two interface versions, 0.9.80a and 0.9.80b, for example
31 All those interfaces and groups could be file links --
32 lib_interfacegroup_interface1.a would link to libinterface1.a.
34 If there is 1 library with 2 sets of minimal functionality, then it's
35 questionable, how to implement both (there would be linker error in
36 some cases) -- which makes this conception weaker.
38 Anyway, when standard interfaces are used and linked, that would help a bit.
40 Anyway -- why should i check dependencies *after* building of a big
41 pack, maybe hours of building, when i can check it without even
42 downloading it, when there is nice portage tree? And, i think that
43 making it binary would allow too much bad style -- there are imho
44 things, which should not be automated without very-very careful
45 thinking even if one can only win with automating them in theory and
46 portage tree is most definitely one of them.
48 > Paul
49 >
50 > --
51 > Paul de Vrieze
52 > Gentoo Developer
53 > Mail: pauldv@g.o
54 > Homepage:
55 >
56 >
57 >
60 --
61 tvali
62 (e-mail: "qtvali@×××××.com"; msn: "qtvali@×××××.com";
63 icq: "317-492-912")
65 I like net more than life, cause if i do something wrong, then people
66 in net will tell me that i do, so that i can fix it -- people in life
67 will tell others that i do.
69 --
70 gentoo-portage-dev@g.o mailing list


Subject Author
Re: [gentoo-portage-dev] DB and binary dependency Paul de Vrieze <pauldv@g.o>