RE: [png-mng-implement] -version-number and BeOS

[Nicolas Mendoza]

From: Christian Biesinger
> > It seems to me that this is a bug in any case. Not only is 
> > -version-number inconsistent with -version-info here. Even if BeOS has a 
> > versioning system for libraries and libtool gets support for that, this 
> > would still leave -version-number broken for other platforms where 
> > version_type=none (seems to be amigaos, os2 and sysv4 (in some cases)).

> It's like evaluating 0/0 - on an OS with no version numbering there is
<no defined way to map the non-existent OS version number back to the
> corresponding version info data.

> The fix isn't really a hack because it simply defines that such OSes
> go through the path shared by linux, macos(darwin) and windows.  The
> result is later discarded by the version-info code so the actual values
> are not important.  An alternative fix is to simply set all the values
> to '1', but that would be a bigger change...

> It would be better if we could use version-info across all the platforms,
> but it is not possible to obtain consistent behaviour across the various
> platforms with a single set of current:age:revision.  That's because
> some platforms produce a 'major' of (current-age) and some calculate a
> major of (current).  With libpng we ensure that minor package revisions
> (e.g. package 1.2.8->1.2.9) change the ABI compatibly, so we need the
> 'major' to remain constant on all platforms across a minor package
> revision.

> For example compare the code for the determination of major in the
> cases for freebsd-elf (major=".$current") and linux
> (major=".($current - $age)".  This defines an inconsistent set of ABI
> versions for any package currently running on both FreeBSD and Linux
> (even though the semantic of a major version change is defined the
> same on FreeBSD as Linux - indeed it is actually documented on
> FreeBSD!)  A compatible ABI change, such as the add of a new
> interface, increments current and age, so the major remains
> unchanged (compatible ABI) on Linux but there is a new ABI on
> FreeBSD.

> Fortunately -version-number does what libpng requires - ensures that
> the major version *only* changes on an incompatible ABI change.  Apart
> from the two bugs (failure in 'none' and irix fails if the major version
> number is 0) we haven't seen any problems (yet).

I've seem to have run into a similar problem, what _is_ really the problem?

/bin/sh ../libtool --tag=CC --mode=link ppc-amigaos-gcc  -g -O2 -Wall -W    
-o libtiff.la -rpath /usr/local/amiga/lib -no-undefined -version-number  
3:8:2  tif_aux.lo tif_close.lo tif_codec.lo tif_color.lo tif_compress.lo  
tif_dir.lo tif_dirinfo.lo tif_dirread.lo tif_dirwrite.lo tif_dumpmode.lo  
tif_error.lo tif_extension.lo tif_fax3.lo tif_fax3sm.lo tif_flush.lo  
tif_getimage.lo tif_jpeg.lo tif_luv.lo tif_lzw.lo tif_next.lo tif_ojpeg.lo  
tif_open.lo tif_packbits.lo tif_pixarlog.lo tif_predict.lo tif_print.lo  
tif_read.lo tif_strip.lo tif_swab.lo tif_thunder.lo tif_tile.lo  
tif_unix.lo tif_version.lo tif_warning.lo tif_write.lo tif_zip.lo  
../port/libport.la -ljpeg -lz -lm -lc
libtool: link: CURRENT `' must be a nonnegative integer
libtool: link: `3:8:2' is not valid version information


--
Nicolas Mendoza
http://utilitybase.com