[comp.sys.sun] f77 1.3.1 incompatabilites

doug@seismo.gps.caltech.edu (10/08/90)

WARNING:  f77 1.3.1 INCOMPATIBLE with f77 1.2 (and earlier) object code.

Sun advised (on page 11 of their RTF) that you should not mix LIBRARIES
for FORTRAN 1.2 and FORTRAN 1.3.  However, Sun has discovered that there
is an incompatibility between the OBJECT CODE created by the 1.2 compiler
and the libraries associated with 1.3.1.

What this means is that .o files or .a files created with the 1.2 (or
earlier) compiler will not work correctly with new code generated by the
1.3.1 compiler.  Sun changed the interfaces between their I/O routines, so
that the datatype descriptor values are different between the two compiler
revisions.  This means that, for example, old objects doing I/O using the
new I/O libraries will be signalling the wrong descriptor codes.  

The end result is that object code (.o files or .a files composed of .o
files) created with the 1.2 compiler SHOULD NOT BE LINKED WITH f77 1.3.1
AND ITS LIBRARIES.  The resulting program may APPEAR to execute correctly,
but may compute or output INCORRECT RESULTS.

Due to this incompatiblity, Sun is now recommending that users recompile
ALL ROUTINES before linking them with the f77 1.3.1 compiler and
libraries.

Sun says they will now emphasize to its customers the need to recompile
FORTRAN programs for use with the current compiler, as the RTF did not
bring mention this.  In addition, they should be making this information
available to its customer base, sales force, and third-party software
vendors as soon as possible.

So, the warning	(when changing to f77 1.3.1) is:

1.	RECOMPILE ALL LOCAL FORTRAN-based libraries.
2.	Inform users to RECOMPILE ALL FORTRAN source code (including those in
	private libraries) before using them with the new compiler.
3.	Contact ALL suppliers of third-party software that supply you with
	object code libraries and inform them you need new versions compiled 
	with the current 1.3.1 compiler.

Doug Neuhauser			Div. of Geological and Planetary Sciences
doug@seismo.gps.caltech.edu	California Institute of Technology
818-356-3993			MS 252-21, Pasadena, CA  91125