[fpc-devel] FPC dynamic libraries

[Bogusław Brandys]

Michael Van Canneyt wrote:
> 
> On Thu, 8 Feb 2007, George Birbilis wrote:
> 
>>>>> We need a version system.
>>>> That's not something "we" need, but which most OS'es need 
>>> (and don't 
>>>> provide, except for hacks like symlinks or different filenames).
>>>> Moreover, it doesn't really solve much unless you like having 20 
>>>> different versions of the same shared library on your system (which 
>>>> would more or less defeat the purpose of saving space, although it 
>>>> could still save memory if more than one FPC program is 
>>> running at the 
>>>> same time).
>>> If I understand well what you mean, Vista has versioning of 
>>> that kind, you can ask to see older versions of any file and 
>>> restore the one you want. A small caveat is that for files 
>>> that don't exist currently anymore (deleted) there's no GUI 
>>> to get them (or one I haven't spotted yet) and you need to 
>>> make a dummy file with same name, then right click it and go 
>>> to Properties, then ask for the older versions (there's a 
>>> special tab for that on the dialog). Not sure if the Basic 
>>> version of Vista has this functionality available (I tried it 
>>> with Vista Ultimate)
>> If you meant having many libs of different version exist side-by-side, .NET
>> runtime supports it, but Win32 itself doesn't
> 
> Most unixes also have it. The point is that it kind of defeats the purpose.
> Having 20+ libraries called fpcrtl-xyz.dll (or fpcrtl.so.x.y.z on unixes)
> defeats the purpose of a shared library: saving disk and (more importantly)
> memory space by factoring out common code. 
> 
> If we'd know that the fpcrtl.so (or .dll) interface will stay the same in the 
> next 5 years, it makes sense to distribute this. Since the interface changes
> still wildly, it's a bad idea.
> 
> Look at Delphi packages: as soon as the interface of a package changes,
> you must re-compile all the binaries that use it. The same would be true 
> for FPC. I can assure you this is a major headache when distributing apps.
> 
> Michael.

Is that so hard to use version system for rtl libraries ? I think that 
most of Lazarus end users will work with one fpc version and no other.

Lazarus developers still need fpc SVN and here is required a way to fast 
rebuild lazarus with fpc rtl which is nothing more that we are doing all 
the time now ;-) End users sometimes will need to rebuild lazarus and 
fpc also if some critical bugs are fixed in fpc but : is it something 
extraordinary  ?


Am I missing something ?

Regards
Boguslaw Brandys