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From: "Bil.Kleb at NASA dot gov" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/53940] warn about duplicate USE
Date: Thu, 12 Jul 2012 13:25:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53940

--- Comment #2 from Bil Kleb <Bil.Kleb at NASA dot gov> 2012-07-12 13:25:29 UTC ---
I guess I see the USE ONLY as similar to a declaration, and to have two of the
same declarations in a program is an error, e.g.,

$ cat duplicate_declaration.f90 << EOF
program duplicate_declaration
  integer :: var
  integer :: var ! should produce at least a warning?
  var = 1
  print*, var
end program
EOF

% gfortran duplicate_declaration.f90 
duplicate_declaration.f90:3.16:

  integer :: var ! should produce at least a warning?
                1
Error: Symbol 'var' at (1) already has basic type of INTEGER

While the error is mostly harmless, we find it useful to know about to keep our
code clean.