[Bug fortran/44430] New: [4.6 Regression] Infinite recursion with -fdump-parse-tree

[Bug fortran/44430] New: [4.6 Regression] Infinite recursion with -fdump-parse-tree

[tkoenig at gcc dot gnu dot org]

This is with revision 160336.

$ cat > a.f90
subroutine foo(a,b)
  real :: a(10), b(5)
  a(1:5) = b
end
$ gfortran -fdump-parse-tree a.f90 |  head -40

        Namespace: A-H: (REAL 4) I-N: (INTEGER 4) O-Z: (REAL 4)
        procedure name = foo
        symtree: __convert_i4_i8  Ambig 0
        symbol __convert_i4_i8 (INTEGER 8)(PROCEDURE UNKNOWN-INTENT
UNKNOWN-ACCESS UNKNOWN-PROC UNKNOWN FUNCTION ELEMENTAL PURE)
        result: __convert_i4_i8

        symtree: a  Ambig 0
        symbol a (REAL 4)(VARIABLE UNKNOWN-INTENT UNKNOWN-ACCESS UNKNOWN-PROC
UNKNOWN DIMENSION DUMMY)
        Array spec:(1 [0] AS_EXPLICIT 1 10 )

        symtree: b  Ambig 0
        symbol b (REAL 4)(VARIABLE UNKNOWN-INTENT UNKNOWN-ACCESS UNKNOWN-PROC
UNKNOWN DIMENSION DUMMY)
        Array spec:(1 [0] AS_EXPLICIT 1 5 )

        symtree: foo  Ambig 0
        symbol foo (UNKNOWN 0)(PROCEDURE UNKNOWN-INTENT UNKNOWN-ACCESS
UNKNOWN-PROC UNKNOWN SUBROUTINE)
        Formal arglist: a b
        Formal namespace
          Namespace: A-H: (REAL 4) I-N: (INTEGER 4) O-Z: (REAL 4)
          procedure name = foo
          symtree: __convert_i4_i8  Ambig 0
          symbol __convert_i4_i8 (INTEGER 8)(PROCEDURE UNKNOWN-INTENT
UNKNOWN-ACCESS UNKNOWN-PROC UNKNOWN FUNCTION ELEMENTAL PURE)
          result: __convert_i4_i8

          symtree: a  Ambig 0
          symbol a (REAL 4)(VARIABLE UNKNOWN-INTENT UNKNOWN-ACCESS UNKNOWN-PROC
UNKNOWN DIMENSION DUMMY)
          Array spec:(1 [0] AS_EXPLICIT 1 10 )

          symtree: b  Ambig 0
          symbol b (REAL 4)(VARIABLE UNKNOWN-INTENT UNKNOWN-ACCESS UNKNOWN-PROC
UNKNOWN DIMENSION DUMMY)
          Array spec:(1 [0] AS_EXPLICIT 1 5 )

          symtree: foo  Ambig 0
          symbol foo (UNKNOWN 0)(PROCEDURE UNKNOWN-INTENT UNKNOWN-ACCESS
UNKNOWN-PROC UNKNOWN SUBROUTINE)
          Formal arglist: a b
          Formal namespace
            Namespace: A-H: (REAL 4) I-N: (INTEGER 4) O-Z: (REAL 4)
            procedure name = foo
            symtree: __convert_i4_i8  Ambig 0
            symbol __convert_i4_i8 (INTEGER 8)(PROCEDURE UNKNOWN-INTENT
UNKNOWN-ACCESS UNKNOWN-PROC UNKNOWN FUNCTION ELEMENTAL PURE)
            result: __convert_i4_i8

            symtree: a  Ambig 0
            symbol a (REAL 4)(VARIABLE UNKNOWN-INTENT UNKNOWN-ACCESS
UNKNOWN-PROC UNKNOWN DIMENSION DUMMY)
            Array spec:(1 [0] AS_EXPLICIT 1 10 )

            symtree: b  Ambig 0
            symbol b (REAL 4)(VARIABLE UNKNOWN-INTENT UNKNOWN-ACCESS
UNKNOWN-PROC UNKNOWN DIMENSION DUMMY)
            Array spec:(1 [0] AS_EXPLICIT 1 5 )

... and so on.


-- 
           Summary: [4.6 Regression] Infinite recursion with -fdump-parse-
                    tree
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: tkoenig at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.6 Regression] Infinite recursion with -fdump-parse-tree

[tkoenig at gcc dot gnu dot org]

-- 

tkoenig at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.6.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.6 Regression] Infinite recursion with -fdump-parse-tree

[dominiq at lps dot ens dot fr]

------- Comment #1 from dominiq at lps dot ens dot fr  2010-06-06 10:32 -------
gcc version 4.4.4 gives

        Namespace: A-H: (REAL 4) I-N: (INTEGER 4) O-Z: (REAL 4)
        procedure name = foo
        symtree: __convert_i4_i8  Ambig 0
        symbol __convert_i4_i8 (INTEGER 8)(PROCEDURE UNKNOWN-INTENT
UNKNOWN-ACCESS UNKNOWN-PROC UNKNOWN FUNCTION ELEMENTAL PURE)

        symtree: a  Ambig 0
        symbol a (REAL 4)(VARIABLE UNKNOWN-INTENT UNKNOWN-ACCESS UNKNOWN-PROC
UNKNOWN DIMENSION DUMMY)
        Array spec:(1 AS_EXPLICIT 1 10 )

        symtree: b  Ambig 0
        symbol b (REAL 4)(VARIABLE UNKNOWN-INTENT UNKNOWN-ACCESS UNKNOWN-PROC
UNKNOWN DIMENSION DUMMY)
        Array spec:(1 AS_EXPLICIT 1 5 )

        symtree: foo  Ambig 0
        symbol foo (UNKNOWN 0)(PROCEDURE UNKNOWN-INTENT UNKNOWN-ACCESS
UNKNOWN-PROC UNKNOWN SUBROUTINE)
        Formal arglist: a b


      ASSIGN foo:a(1_8:5_8) foo:b(FULL)


        Namespace: A-H: (REAL 4) I-N: (INTEGER 4) O-Z: (REAL 4)
        procedure name = MAIN__
        symtree: MAIN__  Ambig 0
        symbol MAIN__ (UNKNOWN 0)(PROGRAM UNKNOWN-INTENT PUBLIC UNKNOWN-PROC
UNKNOWN SUBROUTINE)

The infinite recursion occurs also for gcc version 4.5.0.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[tkoenig at gcc dot gnu dot org]

-- 

tkoenig at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
      Known to fail|                            |4.5.0 4.6.0
      Known to work|                            |4.4.1
   Last reconfirmed|0000-00-00 00:00:00         |2010-06-06 11:22:49
               date|                            |
            Summary|[4.6 Regression] Infinite   |[4.5/4.6 Regression]
                   |recursion with -fdump-parse-|Infinite recursion with -
                   |tree                        |fdump-parse-tree


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[tkoenig at gcc dot gnu dot org]

------- Comment #2 from tkoenig at gcc dot gnu dot org  2010-06-06 20:15 -------
This was between rev. 149577 (works) and rev. 149607 (does not work).

Still narrowing it down a bit.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[dominiq at lps dot ens dot fr]

------- Comment #3 from dominiq at lps dot ens dot fr  2010-06-06 20:39 -------
> This was between rev. 149577 (works) and rev. 149607 (does not work).

The only candidate I see is 149586.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[tkoenig at gcc dot gnu dot org]

------- Comment #4 from tkoenig at gcc dot gnu dot org  2010-06-06 20:52 -------
I agree.  Rev. 149586 is:

2009-07-13  Janus Weil  <janus@gcc.gnu.org>

       PR fortran/40646
       * module.c (mio_symbol): If the symbol has formal arguments,
       the formal namespace will be present.
       * resolve.c (resolve_actual_arglist): Correctly handle 'called'
       procedure pointer components as actual arguments.
       (resolve_fl_derived,resolve_symbol): Make sure the formal namespace
       is present.
       * trans-expr.c (gfc_conv_procedure_call): Correctly handle the formal
       arguments of procedure pointer components.

(nothing else suspicious in that range.

Janus?


-- 

tkoenig at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |janus at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[janus at gcc dot gnu dot org]

------- Comment #5 from janus at gcc dot gnu dot org  2010-06-06 21:31 -------
I'm afraid you're right. r149586 indeed seems to be the culprit. The bug goes
away when reverting a part of that commit, more precisely this one:

Index: gcc/fortran/resolve.c
===================================================================
--- gcc/fortran/resolve.c       (revision 160347)
+++ gcc/fortran/resolve.c       (working copy)
@@ -11661,20 +11655,6 @@ resolve_symbol (gfc_symbol *sym)
       && !sym->attr.contained && !sym->attr.intrinsic)
     gfc_resolve (sym->formal_ns);

-  /* Make sure the formal namespace is present.  */
-  if (sym->formal && !sym->formal_ns)
-    {
-      gfc_formal_arglist *formal = sym->formal;
-      while (formal && !formal->sym)
-       formal = formal->next;
-
-      if (formal)
-       {
-         sym->formal_ns = formal->sym->ns;
-         sym->formal_ns->refs++;
-       }
-    }
-
   /* Check threadprivate restrictions.  */
   if (sym->attr.threadprivate && !sym->attr.save && !sym->ns->save_all
       && (!sym->attr.in_common


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[janus at gcc dot gnu dot org]

------- Comment #6 from janus at gcc dot gnu dot org  2010-06-06 21:45 -------
A simple way to fix this:

Index: gcc/fortran/dump-parse-tree.c
===================================================================
--- gcc/fortran/dump-parse-tree.c       (revision 160347)
+++ gcc/fortran/dump-parse-tree.c       (working copy)
@@ -853,7 +853,7 @@ show_symbol (gfc_symbol *sym)
        }
     }

-  if (sym->formal_ns)
+  if (sym->formal_ns && (sym->formal_ns != sym->ns))
     {
       show_indent ();
       fputs ("Formal namespace", dumpfile);


I'm not 100% sure yet if this is the *proper* way, but I'll try to find out.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[janus at gcc dot gnu dot org]

-- 

janus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |janus at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2010-06-06 11:22:49         |2010-06-06 21:46:01
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[janus at gcc dot gnu dot org]

------- Comment #7 from janus at gcc dot gnu dot org  2010-06-06 21:50 -------
(In reply to comment #5)
> The bug goes away when reverting a part of that commit

Of course simply reverting that part causes a couple of regressions, e.g.
proc_ptr_1,10,22 and others.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[janus at gcc dot gnu dot org]

------- Comment #8 from janus at gcc dot gnu dot org  2010-06-09 18:38 -------
Subject: Bug 44430

Author: janus
Date: Wed Jun  9 18:38:11 2010
New Revision: 160504

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=160504
Log:
2010-06-09  Janus Weil  <janus@gcc.gnu.org>

        PR fortran/44430
        * dump-parse-tree.c (show_symbol): Avoid infinite loop.

Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/dump-parse-tree.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[janus at gcc dot gnu dot org]

------- Comment #9 from janus at gcc dot gnu dot org  2010-06-12 04:02 -------
Subject: Bug 44430

Author: janus
Date: Sat Jun 12 04:02:27 2010
New Revision: 160645

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=160645
Log:
2010-06-12  Janus Weil  <janus@gcc.gnu.org>

        PR fortran/44430
        * dump-parse-tree.c (show_symbol): Avoid infinite loop.


Modified:
    branches/gcc-4_5-branch/gcc/fortran/ChangeLog
    branches/gcc-4_5-branch/gcc/fortran/dump-parse-tree.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430

[Bug fortran/44430] [4.5/4.6 Regression] Infinite recursion with -fdump-parse-tree

[janus at gcc dot gnu dot org]

------- Comment #10 from janus at gcc dot gnu dot org  2010-06-12 04:03 -------
Fixed on trunk and 4.5. Closing.


-- 

janus at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44430