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(g77-295.info)Prefer Automatic Uninitialized Variables

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Prefer Automatic Uninitialized Variables
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   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 `SAVE's every local
non-automatic variable and array, affects even things like `DO'
iteration variables, which rarely need to be `SAVE'd, and this often
reduces run-time performances.  Similarly, `-fno-init-local-zero'
forces such variables to be initialized to zero--when `SAVE'd (such as
when `-fno-automatic'), this by itself generally affects only startup
time for a program, but when not `SAVE'd, it can slow down the
procedure every time it is called.

   Note: 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.