[pacman-dev] [PATCH] add support for .so dependencies

[Allan McRae]

I like to take a step back for a while and think about why a feature is 
needed in pacman/makepkg (especially from a not Arch perspective as 
pacman aims to be distro agnostic)


So, the issue is sometimes library version mismatches/missingness break 
a users system.  From a pacman/makepkg stand point, how does this occur?

In a "stable release" distro, this should never occur.  Library 
differences should only happen between releases which will require a 
user chaning repos and doing a full -Syu.

 From experience with Arch, this situation can occur In a rolling 
release when
1) a user installs a package with "pacman -Sy pkg" and version deps 
cause other packages to be updated
2) with the use of SyncFirst and non/wrong versioned deps.

Case #2 occurred with pacman and was corrected by correcting the 
versioned dep.  Also, it would not have occurred if -Wl,--as-needed was 
used.  Automatic .so deps would have stopped it but so would have 
correctly versioned deps.  So in that situation we already have the 
tools to deal with this.

Case #1 is a case whether this could be useful.  But has anyone thought 
about why this is happening more that it used to?  Surely there were 
lots of people who did a "pacman -Sy pkg" in the past.  The answer... 
excess versioned deps.  If we had no versioned deps, only that package 
specifically being updated would be affected.  In general people would 
not tend to do a "-Sy pkg" with a library and thus the lack of versioned 
deps only ever caused a minor inconvenience to the user who did the 
wrong thing.

Adding sodeps would just make it difficult for people to do a "pacman 
-Sy pkg" and those people would end up doing a "-Sd pkg", which would 
have the same result as no versioned deps.

I think a better approach is to have a very few system critical packages 
providing/depending on the relevant libs and stop over using versioned deps.

Allan