FORTRAN Reference Manual

Compiler Directives
FORTRAN Reference Manual—528615-001
10-40
LARGECOMMON Compiler Directive
Example
?INTEGER*4
LARGECOMMON Compiler Directive
The LARGECOMMON directive tells FORTRAN to allocate space for common blocks
in extended memory.
If you specify block names in the LARGECOMMON directive, FORTRAN uses
extended memory for each common block you specify in the directive.
If you omit block names from the LARGECOMMON directive, FORTRAN uses
extended memory for all common blocks in the compilation that you do not explicitly
specify in HIGHCOMMON directives.
block-name
is the name of a common block.
Considerations
•
Use of the LARGECOMMON Directive
You must specify LARGECOMMON either with the FORTRAN command (after the
semicolon following the object file name), or in your source file before the first
FORTRAN statement.
If you specify the LARGECOMMON directive, FORTRAN compiles your program
as if you had specified an EXTENDEDREF directive, even if you did not include an
EXTENDEDREF directive. (For additional considerations, see the EXTENDEDREF
Compiler Directive on page 10-24.)
You cannot use the LARGECOMMON directive in a compilation that specifies
NOEXTENDEDREF.
If you use both the LARGECOMMON and HIGHCOMMON directives in the same
compilation, at least one of the two directives must include one or more block
names. You cannot specify the same block name in both a LARGECOMMON and
HIGHCOMMON directive.
Do not use the LARGECOMMON directive in programs that call Guardian
procedures such as SEGMENT_ALLOCATE_ to allocate extended data space.
Your direct handling of extended data space—through calls to Guardian
procedures—can interfere with the memory management required for the
LARGECOMMON
block name–
block name , block name–[]. . .–()
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