J3/10-244
To: J3
From: Malcolm Cohen
Subject: Implicit typing in derived types
Date: 2010 October 12

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NUMBER: F03/0123
TITLE: 	Implicit typing in derived types
KEYWORDS: Derived types, implicit typing
DEFECT TYPE: Interpretation
STATUS: J3 consideration in progress

QUESTION:

Consider the program

       PROGRAM MAIN
         TYPE T
           INTEGER :: I = BIT_SIZE(J)
         END TYPE
         ! J = 0
         CALL SUBR1
       CONTAINS
         SUBROUTINE SUBR1
           J = 1
           CALL SUBR2
           PRINT *, J
         END SUBROUTINE
         SUBROUTINE SUBR2
           J = 2
         END SUBROUTINE
       END

Q1. Is this program standard-conforming?
    (In particular, is it permitted to have the first, or only,
     appearance of a local variable name appear within a type
     definition.  The definition of implicit typing says that
     J is explicitly declared within T.)

Q2. (a) If not, is it standard-conforming if the comment "! J = 0" is
        turned into the assignment statement "J = 0"?
    (b) If it is standard-conforming, what does it print?
        (If J is a local variable of MAIN, it should print 2.)

ANSWER:

A1. Yes, the program is standard-conforming.  The definition of
    implicit typing is erroneous - J is a local entity of MAIN.
    An edit is supplied to correct this error.

A2. (a) Not applicable.
    (b) The program will print the value 2.

EDITS to 10-007:

[109:22-23] In 5.5p4,
  After
    "The data entity is treated as if it were declared in an explicit
     type declaration"
  replace "in" with "; if",
  then after "the outermost inclusive scope in which it appears"
  insert
    "is not a type definition, it is declared in that scope, otherwise
     it is declared in the host of that scope".

Note: This makes the whole sentence read
  "The data entity is treated as if it were declared in an explicit
   type declaration; if the outermost inclusive scope in which it
   appears is not a type definition, it is declared in that scope,
   otherwise it is declared in the host of that scope".

SUBMITTED BY: Robert Corbett (via Van Snyder via Dan Nagle)

HISTORY: 08-268    m185  F03/0123 submitted
         10-nnn    m193  Revised answer.

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