The SAVE attribute causes the values and definition of objects to be retained after execution of a RETURN or END statement in a subprogram.
The SAVE attribute can be specified in a type declaration statement or a SAVE statement, and takes one of the following forms:
Type Declaration Statement:
Rules and Behavior
In Compaq Fortran, certain variables are given the SAVE attribute, or not, by default:
To enhance portability and avoid possible compiler warning messages, Compaq recommends that you use the SAVE statement to name variables whose values you want to preserve between subprogram invocations.
When a SAVE statement does not explicitly contain a list, all allowable items in the scoping unit are saved.
A SAVE statement cannot specify the following (their values cannot be saved):
Even though a common block can be included in a SAVE statement, individual variables within the common block can become undefined (or redefined) in another scoping unit.
If a common block is saved in any scoping unit of a program (other than the main program), it must be saved in every scoping unit in which the common block appears.
A SAVE statement has no effect in a main program.
The following example shows a type declaration statement specifying the SAVE attribute:
SUBROUTINE TEST() REAL, SAVE :: X, Y
The following is an example of the SAVE statement:
SAVE A, /BLOCK_B/, C, /BLOCK_D/, E
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