Sun 3 vs uVAXII floating point speed....

[Chuck Karish]

In article <247 at texhrc.UUCP> ldm at texhrc.UUCP (Lyle Meier) writes:
>Should
>you wish to call a C program from the fortran, you need to write a bridge 
>routine in something called a jacket building language. This is because the
>VAX fortran compiler insists on passing charater variables by descriptor ...

The jacket building language is simple and easy to use, though the manual
is not as helpful as it might be, and had (has?) some serious errors in
its examples.  Most jacket routines are one-line programs that simply
declare the name of the routine and the types of the parameters for
both C and Fortran.

VAX Fortran for Ultrix is a useful tool for many Fortran users, for two
reasons:

	1) It's compatible with VMS Fortran, which is the source of
	   many programs that have to be ported.

	2) It's tailored for the VAX, and is fast.  Probably still
	   faster than the 4.3 version of f77; has anyone compared?

Under Ultrix, VAX Fortran makes executables that are bigger than f77
executables, and bigger than they would be under VMS.  This is because
under VMS the Fortran runtime library stays in shared memory, so the
developers favored speed over size.  Under Ultrix, those big library
routines get linked into every executable.

Chuck Karish	ARPA:	karish at denali.stanford.edu
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