Re: [atlas-devel] change in dynamic build

[Jean-François M. <jf...@co...>]

A short _ belated _ reply to Clint's mail of dec 30.

The proposal looks excellent _ and basically makes sense
as well for MacOSX.

A)
Concerning the split-up in 3 libraries _ looks w/o problem to me...
But I would have a priori a tendency to have separate libs for
separate API's, like BLAS and LAPACK _ especially when one looks much
more stable than the other _ , and thus maybe copy the current 4 way
split of the static libs rather than the proposed 3-way split.
For about every pkg I know, static and shared libs correspond in a
1 to 1 way, and doing this differently would involve non-trivial  
additional
work: really strong reasons would be neeeded in my view to depart from  
this
almost universal practice.

I'm a bit less sensitive/sympathetic to incomplete builds of atlas:  
seems
to me that nowadays there is a fortran installable on about evey  
platform,
and that anybody can download lapack; as a consequence, I would see no  
harm
if building shared libs was restricted to complete builds.
I look primarily for functionality, correpomdence with API, stability,
decreasing memory footprint for applications, keeping number of exported
symbols reasonably low...

B) Concerning the names of the libraries, implementation (porting to  
MacOSX)
will be slightly easier with names of the form libfoo.VSTRING.Suffix,  
wher
"suffix" stands for "so" or "dylib", and VSTRING stands for the full  
version
string (like Major.minor.patch _ but cf C below) _ so the SONAME can be
just libfoo.Major.so and on MacOSX the install_name /abs/path/to/ 
libfoo.Major.dylib.
Indeed this order seems mandatory on MacOSX...

C) Versioning : still would be safe to follow systematically libtool's  
method
for versioning, for full consistency across releases and OS's, and  
thus, w/o
necessarily using libtool itself, use at least its algorithm behind
-version-info CURRENT[:REVISION[:AGE]]
(cf. `info glibtool` 4) Invoking libtool 4.2) Link mode
cf. alse Note 'Versioning' there)
[  or alternatively (but depreated) -version-number  
MAJOR[:MINOR[:REVISION]]  ]

E.g., plunder just that algorithm from ltmain.sh , or use some  
invocation
of glibtool --dry-run...

JF Mertens