[Bug fortran/42267] New: interaction between -finit-local-zero and -fno-automatic

[bdavis at gcc dot gnu dot org]

when using both flags, the variables are initialized on every function call. 
see the example below:


bash-3.2$ cat lvar.f 
       REAL A(100)
       PRINT*,'Expect them to be zero'
       CALL ONE
       PRINT*,'Expect them to be 1..10'
       CALL TWO
       PRINT*,'Expect them to be 1..10'
       CALL ONE
       END
       SUBROUTINE ONE
       REAL A(100)
       INTEGER I
       PRINT*,"Sub One Loc(a) is ",LOC(A)
       DO I=1,10
          PRINT*,A(I)
          A(I) = I
       END DO
       END
       SUBROUTINE TWO
       REAL A(100)
       INTEGER I
       PRINT*,"Sub Two Loc(a) is ",LOC(A)
       DO I = 1,10
         A(I) = 0
       END DO
       END
bash-3.2$ /usr/local/bin/gfortran -static lvar.f -finit-local-zero
-fno-automatic
bash-3.2$  /usr/local/bin/gfortran --version
GNU Fortran (GCC) 4.4.1
Copyright (C) 2009 Free Software Foundation, Inc.

GNU Fortran comes with NO WARRANTY, to the extent permitted by law.
You may redistribute copies of GNU Fortran
under the terms of the GNU General Public License.
For more information about these matters, see the file named COPYING

bash-3.2$ ./a.out
 Expect them to be zero
 Sub One Loc(a) is    135144832
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
 Expect them to be 1..10
 Sub Two Loc(a) is    135144416
 Expect them to be 1..10
 Sub One Loc(a) is    135144832
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000    
   0.0000000


-- 
           Summary: interaction between -finit-local-zero and -fno-automatic
           Product: gcc
           Version: 4.4.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bdavis at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42267