http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59103
Bug ID: 59103
Summary: [OOP] Reject deallocate/intent(out) for polymorphic
var in PURE procedures (IR F08/0033)
Product: gcc
Version: 4.9.0
Status: UNCONFIRMED
Keywords: accepts-invalid, diagnostic
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: burnus at gcc dot gnu.org
(This PR is also motivated by
https://groups.google.com/forum/#!topic/comp.lang.fortran/66iSG-kMZfo and
https://groups.google.com/forum/#!topic/comp.lang.fortran/-NaOfgodyYc )
Interpretation request F08/0033,
ftp://ftp.nag.co.uk/sc22wg5/N1851-N1900/N1875.txt, added additional
restrictions to PURE as polymorphic variables might have IMPURE FINAL
subroutines. Thus:
* An INTENT(OUT) argument of a pure procedure should
not be allowed to be polymorphic
* deallocation of any polymorphic entity should be forbidden in
a pure procedure.
* Any statement that might result in a deallocation that is
forbidden should not be allowed in a pure procedure.
Or more formally:
EDITS to 10-007r1:
[24:10] 1.6.2p1 last sentence, "Any"->"Except as identified in this
subclause, any".
{This edit is also present in interp F08/0032.}
[24:11+] 1.6.2 at end of subclause insert new paragraph:
"Fortran 2003 permitted an INTENT(OUT) argument of a pure
subroutine to be polymorphic. This is not permitted by this
part of ISO/IEC 1539.".
[312:23+] After C1278, insert new constraint:
"C1278b An INTENT(OUT) dummy argument of a pure procedure shall not
be polymorphic."
[313:4+] After C1284, insert new constraint and note:
"C1284a A statement that might result in the deallocation of a
polymorphic entity is not permitted in a pure procedure.
Note 12.48x
Apart from the DEALLOCATE statement, this includes intrinsic
assignment if the variable has a polymorphic allocatable component
at any level of component selection that does not involve a pointer
component but which might involve one or more allocatable
components."
Example:
See interpretation request.
