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(g77-295.info)Large Initialization

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Initialization of Large Aggregate Areas
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   A warning message is issued when `g77' sees code that provides
initial values (e.g. via `DATA') to an aggregate area (`COMMON' or
`EQUIVALENCE', or even a large enough array or `CHARACTER' variable)
that is large enough to increase `g77''s compile time by roughly a
factor of 10.

   This size currently is quite small, since `g77' currently has a
known bug requiring too much memory and time to handle such cases.  In
`egcs/gcc/f/data.c', the macro `FFEDATA_sizeTOO_BIG_INIT_' is defined
to the minimum size for the warning to appear.  The size is specified
in storage units, which can be bytes, words, or whatever, on a
case-by-case basis.

   After changing this macro definition, you must (of course) rebuild
and reinstall `g77' for the change to take effect.

   Note that, as of version 0.5.18, improvements have reduced the scope
of the problem for *sparse* initialization of large arrays, especially
those with large, contiguous uninitialized areas.  However, the warning
is issued at a point prior to when `g77' knows whether the
initialization is sparse, and delaying the warning could mean it is
produced too late to be helpful.

   Therefore, the macro definition should not be adjusted to reflect
sparse cases.  Instead, adjust it to generate the warning when densely
initialized arrays begin to cause responses noticeably slower than
linear performance would suggest.