[Boost-build] Boost install: shared libraries

From: Vladimir Prus (ghost_at_[hidden])
Date: 2006-10-21 11:41:28

I've some questions about the way install works with V1 (so that I can 
replicate this in V2). I use current CVS HEAD, and run:

    bjam --with-program_options --prefix=/tmp/boost-test-install-v1 install 

It looks like for each library and property set, three shared library files 
are created, for example:

   libboost_program_options-gcc-1_35.so.1.35.0
   libboost_program_options-gcc-1_35.so (symlink to the above)
   libboost_program_options-gcc.so

When running "readelf -a libboost_program_options-gcc.so" I see:

   0x0000000e (SONAME)                     
   Library soname: [libboost_program_options-gcc-1_35.so.1.35.0]

Which means that if I link to this library, it won't be used at runtime. So, 
why is it created?

Second, more standard symlink scheme is something like (real example):

     /usr/lib/libQtGui.so -> libQtGui.so.4.1.2
     /usr/lib/libQtGui.so.4 -> libQtGui.so.4.1.2
     /usr/lib/libQtGui.so.4.1 -> libQtGui.so.4.1.2
     /usr/lib/libQtGui.so.4.1.2

and the soname is libQtGui.so.4

I gather that the different scheme with Boost might be related to lack of 
binary compatibility between versions, but was this an explicit decision?

Also, should not we guarantee binary compatibility between 1.35.0 and 1.35.1?
If so, then soname should be ".....1.35" and we should have symlink 
from ".1.35" to "1.35.0". 

Should we raise raise the question about binary compability betwen 1.N.M and 
1.N.(M+1) on the devel list?

Thanks,
Volodya