[Bug fortran/30875] New: incorrect error message for valid code

[Bug fortran/30875] New: incorrect error message for valid code

[jv244 at cam dot ac dot uk]

With recent trunk, gfortran incorrectly generates an error for the following
standard code:
TYPE T1
 sequence
 integer :: i=1
END TYPE T1
TYPE T2
 sequence
 integer :: i=1
END TYPE T2
TYPE(T1) :: a1
TYPE(T2) :: a2
EQUIVALENCE(a1,a2)
write(6,*) a1,a2
END


-- 
           Summary: incorrect error message for valid code
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jv244 at cam dot ac dot uk


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30875

[Bug fortran/30875] Equivalence of derived types with (same) default initializer

[burnus at gcc dot gnu dot org]

------- Comment #1 from burnus at gcc dot gnu dot org  2007-02-20 16:39 -------
EQUIVALENCE(a1,a2)
             1
Error: Derived type variable 'a1' at (1) with default initializer cannot be an
EQUIVALENCE object
ffv.f90:11.17:

EQUIVALENCE(a1,a2)
                1
Error: Initialized objects 'a1' and 'a2' cannot both be in the EQUIVALENCE
statement at (1)

Compiles with ifort, g95 and nagf95.


Observations:

If T1 is initialized with "1" and T2 with "2", ifort and nag95 compile it and
g95 rejects it with:
"Memory is initialized more than once (offset 0)"

If run (both "1"):
g95:  1  1 
nagf95: garbage value (twice)
ifort: 1 1

If run with "1", "2":
g95: - (does not compile, see above)
ifort: 2 2
nagf95: garbage value (twice)


-- 

burnus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |rejects-valid
            Summary|incorrect error message for |Equivalence of derived types
                   |valid code                  |with (same) default
                   |                            |initializer


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30875

[Bug fortran/30875] Equivalence of derived types with (same) default initializer

[brooks at gcc dot gnu dot org]

------- Comment #2 from brooks at gcc dot gnu dot org  2007-03-17 23:39 -------
At the end of 14.6.3.3, "Default initialization may be specified for a storage
unit that is storage associated provided the objects or subobjects supplying
the default initialization are of the same type and type parameters, and supply
the same value for the storage unit."

It is somewhat unclear to me from that language whether the relevant constraint
is that A1 and A2 would have to have the "same type and type parameters" (which
they do not, making the code illegal), or whether A1%I and A2%I would have to
have the same type and type parameters (which they do, making the code legal). 
I tried to get some further opinions about this on comp.lang.fortran, but
apparently nobody found my question interesting enough to reply to.  :)

I've now found that MR&C describes this condition as being that the components
in question must have the same type and type parameters, which would make this
legal, and I suspect that's the final answer we'll get.  Thus, I'm confirming
the bug; I can certainly reproduce the error message.


-- 

brooks at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |brooks at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
      Known to fail|                            |4.3.0
   Last reconfirmed|0000-00-00 00:00:00         |2007-03-17 23:39:00
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30875

[Bug fortran/30875] Equivalence of derived types with (same) default initializer

[pault at gcc dot gnu dot org]

------- Comment #3 from pault at gcc dot gnu dot org  2007-05-07 09:45 -------
This will be fixed at the same time as PR29786.  This, in its turn, is awaiting
the fix for PR18769, where Brooks is wading through the necessary gcc
modifications.

Paul


-- 

pault at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |pault at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2007-03-17 23:39:00         |2007-05-07 09:45:54
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30875

[Bug fortran/30875] Equivalence of derived types with (same) default initializer

[pault at gcc dot gnu dot org]

------- Comment #4 from pault at gcc dot gnu dot org  2007-06-11 22:39 -------
Subject: Bug 30875

Author: pault
Date: Mon Jun 11 22:39:21 2007
New Revision: 125628

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=125628
Log:
2007-06-12  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/29786
        PR fortran/30875
        * trans-common.c (get_init_field): New function.
        (create_common): Call get_init_field for overlapping
        initializers in equivalence blocks.
        * resolve.c (resolve_equivalence_derived, resolve_equivalence):
        Remove constraints on initializers in equivalence blocks.
        * target-memory.c (expr_to_char, gfc_merge_initializers):
        New functions.
        (encode_derived): Add the bit offset to the byte offset to get
        the total offset to the field.
        * target-memory.h : Add prototype for gfc_merge_initializers.


2007-06-12  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/29786
        * gfortran.dg/equiv_7.f90: New test.
        * gfortran.dg/equiv_constraint_7.f90: Change error message.


        PR fortran/30875
        * gfortran.dg/equiv_constraint_5.f90: Correct code and error.

Added:
    trunk/gcc/testsuite/gfortran.dg/equiv_7.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/resolve.c
    trunk/gcc/fortran/target-memory.c
    trunk/gcc/fortran/target-memory.h
    trunk/gcc/fortran/trans-common.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gfortran.dg/equiv_constraint_5.f90
    trunk/gcc/testsuite/gfortran.dg/equiv_constraint_7.f90


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30875

[Bug fortran/30875] Equivalence of derived types with (same) default initializer

[pault at gcc dot gnu dot org]

------- Comment #5 from pault at gcc dot gnu dot org  2007-06-11 22:42 -------
Fixed on trunk

Paul


-- 

pault at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30875