[PATCH,fortran]: fix for PR 33760

[Christopher D. Rickett]

hi all,

the attached patch should fix the ICE illustrated by PR 33760. 
bootstrapped and regtested on x86 linux with no new failures.

thanks.
Chris

:ADDPATCH fortran:

ChangeLog entry:

2007-10-15  Christopher D. Rickett  <crickett@lanl.gov>

 	PR fortran/33760
 	* symbol.c (gen_special_c_interop_ptr): Remove code to create
 	constructor for c_null_ptr and c_null_funptr with value of 0.
 	* expr.c (check_init_expr): Prevent check on constructors for
 	iso_c_binding derived types.
 	* resolve.c (resolve_structure_cons): Verify that the user isn't
 	trying to invoke a structure constructor for one of the
 	iso_c_binding derived types.

2007-10-15  Christopher D. Rickett  <crickett@lanl.gov>

 	PR fortran/33760
 	* gfortran.dg/c_ptr_tests_13.f03: New test case.
-------------- next part --------------
Index: gcc/testsuite/gfortran.dg/c_ptr_tests_13.f03
===================================================================
--- gcc/testsuite/gfortran.dg/c_ptr_tests_13.f03	(revision 0)
+++ gcc/testsuite/gfortran.dg/c_ptr_tests_13.f03	(revision 0)
@@ -0,0 +1,12 @@
+! { dg-do compile }
+! Ensure that the user cannot call the structure constructor for one of 
+! the iso_c_binding derived types.
+program main
+   use ISO_C_BINDING
+   implicit none
+   integer(C_INTPTR_T) p
+   type(C_PTR) cptr
+   p = 0
+   cptr = C_PTR(p+1) ! { dg-error "Components of structure constructor" }
+   cptr = C_PTR(1) ! { dg-error "Components of structure constructor" } 
+end program main
Index: gcc/fortran/symbol.c
===================================================================
--- gcc/fortran/symbol.c	(revision 129366)
+++ gcc/fortran/symbol.c	(working copy)
@@ -3354,10 +3354,10 @@ gen_special_c_interop_ptr (int ptr_id, c
   tmp_sym->value->expr_type = EXPR_STRUCTURE;
   tmp_sym->value->ts.type = BT_DERIVED;
   tmp_sym->value->ts.derived = tmp_sym->ts.derived;
+  /* Create a constructor with no expr, that way we can recognize if the user
+     tries to call the structure constructor for one of the iso_c_binding
+     derived types during resolution (resolve_structure_cons).  */
   tmp_sym->value->value.constructor = gfc_get_constructor ();
-  /* This line will initialize the c_null_ptr/c_null_funptr
-     c_address field to NULL.  */
-  tmp_sym->value->value.constructor->expr = gfc_int_expr (0);
   /* Must declare c_null_ptr and c_null_funptr as having the
      PARAMETER attribute so they can be used in init expressions.  */
   tmp_sym->attr.flavor = FL_PARAMETER;
Index: gcc/fortran/expr.c
===================================================================
--- gcc/fortran/expr.c	(revision 129366)
+++ gcc/fortran/expr.c	(working copy)
@@ -2249,7 +2249,10 @@ check_init_expr (gfc_expr *e)
       break;
 
     case EXPR_STRUCTURE:
-      t = gfc_check_constructor (e, check_init_expr);
+      if (e->ts.is_iso_c)
+	t = SUCCESS;
+      else
+	t = gfc_check_constructor (e, check_init_expr);
       break;
 
     case EXPR_ARRAY:
Index: gcc/fortran/resolve.c
===================================================================
--- gcc/fortran/resolve.c	(revision 129366)
+++ gcc/fortran/resolve.c	(working copy)
@@ -728,6 +728,16 @@ resolve_structure_cons (gfc_expr *expr)
   else
     comp = expr->ts.derived->components;
 
+  /* See if the user is trying to invoke a structure constructor for one of
+     the iso_c_binding derived types.  */
+  if (expr->ts.derived && expr->ts.derived->ts.is_iso_c && cons
+      && cons->expr != NULL)
+    {
+      gfc_error ("Components of structure constructor '%s' at %L are PRIVATE",
+		 expr->ts.derived->name, &(expr->where));
+      return FAILURE;
+    }
+
   for (; comp; comp = comp->next, cons = cons->next)
     {
       if (!cons->expr)