The G77 compiler not accurate unless -O3 used

["John Huddleston" <jhudd at lamar dot colostate dot edu>]

Hi Gnu,

If the -O3 option is used to compile fortran code
using the latest g77 compiler 3.2, then the result
is code that works accurately.  If the options

-frename-registers -finline-functions 

are used with -O2 or with -O then accurate code 
is also created.  However, if no optimization is
used then the options do not help.

How do I know the program is accurate with -O3?
The -O3 results agree with the Lahey compiler
using any Lahey option (or not).

Attached is sample code, a runit.sh script to 
compile and test it.  This same problem is 
manifest on the Linux compiler as well.

John Huddleston

Attachment: f2x3.zip
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