ada/4478: Scope of use_package_clause is wrong

[fw at deneb dot enyo dot de]

>Number:         4478
>Category:       ada
>Synopsis:       Scope of use_package_clause is wrong
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          accepts-illegal
>Submitter-Id:   net
>Arrival-Date:   Fri Oct 05 05:26:00 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     Florian Weimer
>Release:        3.1 20011003 (experimental)
>Organization:
>Environment:
System: Linux deneb 2.4.7 #3 Sat Jul 21 09:35:45 CEST 2001 i686 unknown
Architecture: i686
host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: i686-pc-linux-gnu
configured with: ../configure --prefix=/opt/gcc-3
>Description:

With GNAT, the scope of a use_package_clause in a context_clause
incorrectly begins just after the use_package_clause, in contradiction
to RM 8.4(6).  As a consequence, GNAT compiles the illegal spec of
package P3 below.  (This problem was reported by Stephen Cole in
<9pk4t7$tbm$1@trog.dera.gov.uk>.)

>How-To-Repeat:

Run the following code through gnatchop, and try to compile p3.ads.
Compilation should fail, but it doesn't.

--STX
package P1 is pragma Pure; end;
package P1.P2 is pragma Pure; end;

with P1.P2; use P1; use P2;
package P3 is pragma Pure; end;

>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted: