[Bug fortran/47767] [OOP] SELECT TYPE fails to execute correct TYPE IS block

[janus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47767

--- Comment #1 from janus at gcc dot gnu.org 2011-02-16 18:31:06 UTC ---
Here is a variant: Apart from SELECT TYPE, this bug can also be exposed via the
SAME_TYPE_AS intrinsic.


module Tree_Nodes
  type treeNode
   contains
     procedure :: walk
  end type
contains
  subroutine walk (thisNode)
    class (treeNode) :: thisNode
    print *, SAME_TYPE_AS (thisNode, treeNode())
  end subroutine
end module

module Merger_Trees
  use Tree_Nodes
  private
  public :: mergerTree
  type mergerTree
     type(treeNode), pointer :: baseNode
  end type
end module

module Merger_Tree_Build
  use Merger_Trees
end module

program test
  use Merger_Tree_Build
  use Tree_Nodes
  type(treeNode) :: node
  call walk (node)
end program


This prints "F", but should print "T".


The underlying problem seems to be related to the vtable not being properly set
up. The vtab symbol for the type 'treeNode' apparently is present, but it is
not initialized properly: The '_hash' component is 0!

Looking at the mod files, the symbol '__vtab_tree_nodes_Treenode' seems to be
present in tree_nodes.mod and merger_tree_build.mod, but not in
merger_trees.mod!