To: J3                                                     J3/17-242
From: Dan Nagle
Subject: scope of prohibition of DO CONCURRENT
Date: 2017 October 17


Introduction

Paper 183 discusses whether variable declarations in scopes nested
within the block of a DO CONCURRENT are allowed
when DEFAULT ( NONE ) is present.

Subgroup finds the standard is unclear; while it is likely allowed,
it is not clear that "appears", in C1129, applies to the scope
rather than the inclusive scope of the DO CONCURRENT block.

An edit is supplied to clarify the point.



Edits

{against 17-007r2}

{11.1.7.2 Form of the DO construct}

The present C1129:

[191:26-28]

"C1129 If the locality-spec DEFAULT ( NONE ) appears in a DO CONCURRENT
statement, a variable that appears in the block of the construct and
is not an index-name of that construct shall have its locality explicitly
specified."

The edit subgroup agreed rewrites the paragraph,
so the resulting paragraph is supplied:

"C1129 If the locality-spec DEFAULT ( NONE ) appears in a DO CONCURRENT
statement, a variable that is not a construct entity of a construct
within the block of the DO CONCURRENT, is not a statement entity
of a statement within the block of the DO CONCURRENT, and is not
an index-name of that construct, shall not appear in the block
of the DO CONCURRENT unless its locality is specified."

{explicitly carve the contained scopes from the DO block prohibition}