[Bug fortran/49659] New: If-and-condition not obeyed using the g77-compiler (Windows 7, 64-bit).

[Bug fortran/49659] New: If-and-condition not obeyed using the g77-compiler (Windows 7, 64-bit).

[alhoweling at yahoo dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49659

           Summary: If-and-condition not obeyed using the g77-compiler
                    (Windows 7, 64-bit).
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: alhoweling@yahoo.de


Compiling and running the following short sourcecode:

***************************
PROGRAM TEST  
INTEGER A,B,C
LOGICAL M

A=23
B=34
C=55

M=.FALSE.

IF (A.eq.23.AND.B.eq.34.and.C.eq.4.and.M.eqv..FALSE.) THEN
PRINT*, 'yes'
ELSE
PRINT*, 'no'
END IF

END

***************************
gives the following output:

yes

[Bug fortran/49659] If-and-condition not obeyed using the g77-compiler (Windows 7, 64-bit).

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49659

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011.07.06 11:00:29
            Version|unknown                     |4.6.1
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-07-06 11:00:29 UTC ---
Confirmed.

       PROGRAM TEST
       INTEGER C
       LOGICAL M
       C=55
       M=.FALSE.
       IF (C.eq.4.and.M.eqv..FALSE.) THEN
       PRINT*, 'yes'
       ELSE
       PRINT*, 'no'
       END IF
       END

has in .original:

  c = 55;
  m = 0;
  if (c != 4 || !m)
    {
      {
        struct __st_parameter_dt dt_parm.0;

        dt_parm.0.common.filename = &"t.f"[1]{lb: 1 sz: 1};
        dt_parm.0.common.line = 7;
        dt_parm.0.common.flags = 128;
        dt_parm.0.common.unit = 6;
        _gfortran_st_write (&dt_parm.0);
        _gfortran_transfer_character_write (&dt_parm.0, &"yes"[1]{lb: 1 sz: 1},
3);
        _gfortran_st_write_done (&dt_parm.0);
      }
    }

somehow the condition is inverted but the branches are not exchanged
(it's also bogously inverted).

[Bug fortran/49659] If-and-condition not obeyed using the g77-compiler (Windows 7, 64-bit).

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49659

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |INVALID

--- Comment #2 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-07-06 11:03:58 UTC ---
Strangely ifort outputs the same result, so it must be correct (thus,
your program is invalid).  Works with

       IF ((C.eq.4).and.(M.eqv..FALSE.)) THEN

[Bug fortran/49659] If-and-condition not obeyed using the g77-compiler (Windows 7, 64-bit).

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49659

--- Comment #3 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2011-07-06 12:01:59 UTC ---
> Strangely ifort outputs the same result, so it must be correct ...

Indeed! The standard says

7.1.3 Precedence of operators

1 There is a precedence among the intrinsic and extension operations
corresponding to the form of expressions speci ed in 7.1.2, which
determines the order in which the operands are combined unless the order is
changed by the use of parentheses.  This precedence order is summarized in
Table 7.2.  

Table 7.2:

Categories of operations and relative precedence

Category of operation   Operators           Precedence

Extension               defined-unary-op    Highest
Numeric                 **                  .
Numeric                 *, /                .
Numeric                 unary +, -          .
Numeric                 binary +, -         .
Character               //                  .
Relational              .EQ., .NE., .LT., 
                        .LE., .GT., .GE.,
                        ==, /=, <, <=, >, 
                        >=  .
Logical                 .NOT.               .
Logical                 .AND.               .
Logical                 .OR.                .
Logical                 .EQV., .NEQV.       .
Extension               defined-binary-op   Lowest

>From this table 'C.eq.4.and.M.eqv..FALSE.' is computed as
'((C.eq.4).and.M).eqv..FALSE)' which is .TRUE..

> (thus, your program is invalid).

The program is not invalid, but the reporter expectation is.