J3/15-252
To: J3
From: Bill Long
Subject: Restriction on LOCK_TYPE
Date: 2015 October 15
Reference:  J3/15-007r2

Discussion
----------

A lock variable is allowed to be an allocate object in an ALLOCATE
statement according to constraint C1306 [415:16]. There is a
prohibition on the use of such a variable in a SOURCE= specifier of an
ALLOCATE statement in C643 [129:10-12].  The corresponding rules for
event variables are together in the same constraint, C1303
[413:32-33].  The restriction on use in a SOURCE= specifier better
belongs in Clause 6 in a constraint on the syntax rule for ALLOCATE.

Separately, in 6.7.1.1 Form of the ALLOCATE statement, para 4, there
is a similar restriction that variables with dynamic type LOCK_TYPE
are not allowed in a SOURCE= specifier. EVENT_TYPE needs to be
included there.

Edits are provided to address these issues.


Edits to 15-007r2:
------------------

[129:11-12] In C643 (The declared type of <source-expr>...) in 6.7.1.1
Form of the ALLOCATE statement, change "LOCK_TYPE" to "EVENT_TYPE or
LOCK_TYPE" twice.

[129:22-23] In 6.7.1.1 Form of the ALLOCATE statement, para 4, change
"LOCK_TYPE" to "EVENT_TYPE or LOCK_TYPE" twice.

[413:32-33] In the second constraint (C1303) in 13.9.2.9 EVENT_TYPE,
change "as an <allocate-object> in an ALLOCATE statement without a
SOURCE= specifier, as an <allocate-object> in a DEALLOCATE statement"
to "as an <allocate-object>".

{Move the prohibition for an event variable appearing in a SOURCE=
specifier from C1303 to Clause 6.}