If you're using `-fno-automatic' already, you probably should change your code to allow compilation with `-fautomatic' (the default), to allow the program to run faster.
Similarly, you should be able to use `-fno-init-local-zero' (the default) instead of `-finit-local-zero'. This is because it is rare that every variable affected by these options in a given program actually needs to be so affected.
For example, `-fno-automatic', which effectively SAVEs
every local non-automatic variable and array, affects even things like
DO iteration
variables, which rarely need to be SAVEd, and this often reduces
run-time performances.
Similarly, `-fno-init-local-zero' forces such
variables to be initialized to zero--when SAVEd (such as when
`-fno-automatic'), this by itself generally affects only
startup time for a program, but when not SAVEd,
it can slow down the procedure every time it is called.
See section Overly Convenient Command-line Options, for information on the `-fno-automatic' and `-finit-local-zero' options and how to convert their use into selective changes in your own code.
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