1 files changed, 246 insertions, 73 deletions

diff --git a/gcc/fortran/expr.c b/gcc/fortran/expr.c
index d90dd21..257349a 100644
--- a/gcc/fortran/expr.c
+++ b/gcc/fortran/expr.c
@@ -689,6 +689,27 @@ done:
 }
 
 
+static match
+check_specification_function (gfc_expr *e)
+{
+  gfc_symbol *sym;
+  sym = e->symtree->n.sym;
+
+  /* F95, 7.1.6.2; F2003, 7.1.7  */
+  if (sym
+      && sym->attr.function
+      && sym->attr.pure
+      && !sym->attr.intrinsic
+      && !sym->attr.recursive
+      && sym->attr.proc != PROC_INTERNAL
+      && sym->attr.proc != PROC_ST_FUNCTION
+      && sym->attr.proc != PROC_UNKNOWN
+      && sym->formal == NULL)
+    return MATCH_YES;
+
+  return MATCH_NO;
+}
+
 /* Function to determine if an expression is constant or not.  This
    function expects that the expression has already been simplified.  */
 
@@ -715,6 +736,13 @@ gfc_is_constant_expr (gfc_expr *e)
       break;
 
     case EXPR_FUNCTION:
+      /* Specification functions are constant.  */
+      if (check_specification_function (e) == MATCH_YES)
+	{
+	  rv = 1;
+	  break;
+	}
+
       /* Call to intrinsic with at least one argument.  */
       rv = 0;
       if (e->value.function.isym && e->value.function.actual)
@@ -1849,69 +1877,184 @@ not_numeric:
 }
 
 
+static match
+check_init_expr_arguments (gfc_expr *e)
+{
+  gfc_actual_arglist *ap;
 
-/* Certain inquiry functions are specifically allowed to have variable
-   arguments, which is an exception to the normal requirement that an
-   initialization function have initialization arguments.  We head off
-   this problem here.  */
+  for (ap = e->value.function.actual; ap; ap = ap->next)
+    if (check_init_expr (ap->expr) == FAILURE)
+      return MATCH_ERROR;
 
-static try
+  return MATCH_YES;
+}
+
+/* F95, 7.1.6.1, Initialization expressions, (7)
+   F2003, 7.1.7 Initialization expression, (8)  */
+
+static match
 check_inquiry (gfc_expr *e, int not_restricted)
 {
   const char *name;
+  const char *const *functions;
+
+  static const char *const inquiry_func_f95[] = {
+    "lbound", "shape", "size", "ubound",
+    "bit_size", "len", "kind",
+    "digits", "epsilon", "huge", "maxexponent", "minexponent",
+    "precision", "radix", "range", "tiny",
+    NULL
+  };
 
-  /* FIXME: This should be moved into the intrinsic definitions,
-     to eliminate this ugly hack.  */
-  static const char * const inquiry_function[] = {
-    "digits", "epsilon", "huge", "kind", "len", "maxexponent", "minexponent",
-    "precision", "radix", "range", "tiny", "bit_size", "size", "shape",
-    "lbound", "ubound", NULL
+  static const char *const inquiry_func_f2003[] = {
+    "lbound", "shape", "size", "ubound",
+    "bit_size", "len", "kind",
+    "digits", "epsilon", "huge", "maxexponent", "minexponent",
+    "precision", "radix", "range", "tiny",
+    "new_line", NULL
   };
 
   int i;
+  gfc_actual_arglist *ap;
+
+  if (!e->value.function.isym
+      || !e->value.function.isym->inquiry)
+    return MATCH_NO;
 
   /* An undeclared parameter will get us here (PR25018).  */
   if (e->symtree == NULL)
-    return FAILURE;
+    return MATCH_NO;
 
   name = e->symtree->n.sym->name;
 
-  for (i = 0; inquiry_function[i]; i++)
-    if (strcmp (inquiry_function[i], name) == 0)
-      break;
-
-  if (inquiry_function[i] == NULL)
-    return FAILURE;
+  functions = (gfc_option.warn_std & GFC_STD_F2003) 
+		? inquiry_func_f2003 : inquiry_func_f95;
 
-  e = e->value.function.actual->expr;
+  for (i = 0; functions[i]; i++)
+    if (strcmp (functions[i], name) == 0)
+      break;
 
-  if (e == NULL || e->expr_type != EXPR_VARIABLE)
-    return FAILURE;
+  if (functions[i] == NULL)
+    {
+      gfc_error ("Inquiry function '%s' at %L is not permitted "
+		 "in an initialization expression", name, &e->where);
+      return MATCH_ERROR;
+    }
 
   /* At this point we have an inquiry function with a variable argument.  The
      type of the variable might be undefined, but we need it now, because the
-     arguments of these functions are allowed to be undefined.  */
+     arguments of these functions are not allowed to be undefined.  */
 
-  if (e->ts.type == BT_UNKNOWN)
+  for (ap = e->value.function.actual; ap; ap = ap->next)
     {
-      if (e->symtree->n.sym->ts.type == BT_UNKNOWN
-	  && gfc_set_default_type (e->symtree->n.sym, 0, gfc_current_ns)
-	     == FAILURE)
-	return FAILURE;
+      if (!ap->expr)
+	continue;
+
+      if (ap->expr->ts.type == BT_UNKNOWN)
+	{
+	  if (ap->expr->symtree->n.sym->ts.type == BT_UNKNOWN
+	      && gfc_set_default_type (ap->expr->symtree->n.sym, 0, gfc_current_ns)
+	      == FAILURE)
+	    return MATCH_NO;
 
-      e->ts = e->symtree->n.sym->ts;
+	  ap->expr->ts = ap->expr->symtree->n.sym->ts;
+	}
+
+	/* Assumed character length will not reduce to a constant expression
+	   with LEN, as required by the standard.  */
+	if (i == 5 && not_restricted
+	    && ap->expr->symtree->n.sym->ts.type == BT_CHARACTER
+	    && ap->expr->symtree->n.sym->ts.cl->length == NULL)
+	  {
+	    if (gfc_notify_std (GFC_STD_GNU, "assumed character length "
+				"variable '%s' in constant expression at %L",
+				e->symtree->n.sym->name, &e->where) == FAILURE)
+	      return MATCH_ERROR;
+	  }
+	else if (not_restricted && check_init_expr (ap->expr) == FAILURE)
+	  return MATCH_ERROR;
     }
 
-  /* Assumed character length will not reduce to a constant expression
-     with LEN, as required by the standard.  */
-  if (i == 4 && not_restricted
-      && e->symtree->n.sym->ts.type == BT_CHARACTER
-      && e->symtree->n.sym->ts.cl->length == NULL)
-    gfc_notify_std (GFC_STD_GNU, "assumed character length "
-		    "variable '%s' in constant expression at %L",
-		    e->symtree->n.sym->name, &e->where);
+  return MATCH_YES;
+}
+
 
-  return SUCCESS;
+/* F95, 7.1.6.1, Initialization expressions, (5)
+   F2003, 7.1.7 Initialization expression, (5)  */
+
+static match
+check_transformational (gfc_expr *e)
+{
+  static const char * const trans_func_f95[] = {
+    "repeat", "reshape", "selected_int_kind",
+    "selected_real_kind", "transfer", "trim", NULL
+  };
+
+  int i;
+  const char *name;
+
+  if (!e->value.function.isym
+      || !e->value.function.isym->transformational)
+    return MATCH_NO;
+
+  name = e->symtree->n.sym->name;
+
+  /* NULL() is dealt with below.  */
+  if (strcmp ("null", name) == 0)
+    return MATCH_NO;
+
+  for (i = 0; trans_func_f95[i]; i++)
+    if (strcmp (trans_func_f95[i], name) == 0)
+      break;
+
+  if (trans_func_f95[i] == NULL
+      && gfc_notify_std (GFC_STD_F2003, 
+			 "transformational intrinsic '%s' at %L is not permitted "
+			 "in an initialization expression", name, &e->where) == FAILURE)
+    return MATCH_ERROR;
+
+  return check_init_expr_arguments (e);
+}
+
+
+/* F95, 7.1.6.1, Initialization expressions, (6)
+   F2003, 7.1.7 Initialization expression, (6)  */
+
+static match
+check_null (gfc_expr *e)
+{
+  if (strcmp ("null", e->symtree->n.sym->name) != 0)
+    return MATCH_NO;
+
+  return check_init_expr_arguments (e);
+}
+
+
+static match
+check_elemental (gfc_expr *e)
+{
+  if (!e->value.function.isym
+      || !e->value.function.isym->elemental)
+    return MATCH_NO;
+
+  if ((e->ts.type != BT_INTEGER || e->ts.type != BT_CHARACTER)
+      && gfc_notify_std (GFC_STD_F2003, "Extension: Evaluation of "
+			"nonstandard initialization expression at %L",
+			&e->where) == FAILURE)
+    return MATCH_ERROR;
+
+  return check_init_expr_arguments (e);
+}
+
+
+static match
+check_conversion (gfc_expr *e)
+{
+  if (!e->value.function.isym
+      || !e->value.function.isym->conversion)
+    return MATCH_NO;
+
+  return check_init_expr_arguments (e);
 }
 
 
@@ -1925,7 +2068,6 @@ check_inquiry (gfc_expr *e, int not_restricted)
 static try
 check_init_expr (gfc_expr *e)
 {
-  gfc_actual_arglist *ap;
   match m;
   try t;
   gfc_intrinsic_sym *isym;
@@ -1943,42 +2085,44 @@ check_init_expr (gfc_expr *e)
       break;
 
     case EXPR_FUNCTION:
-      t = SUCCESS;
-
-      if (check_inquiry (e, 1) != SUCCESS)
-	{
-	  t = SUCCESS;
-	  for (ap = e->value.function.actual; ap; ap = ap->next)
-	    if (check_init_expr (ap->expr) == FAILURE)
-	      {
-		t = FAILURE;
-		break;
-	      }
-	}
-
-      /* Try to scalarize an elemental intrinsic function that has an
-	 array argument.  */
-      isym = gfc_find_function (e->symtree->n.sym->name);
-      if (isym && isym->elemental
-	    && e->value.function.actual->expr->expr_type == EXPR_ARRAY)
-	{
-	  if (scalarize_intrinsic_call (e) == SUCCESS)
-	    break;
-	}
+      t = FAILURE;
 
-      if (t == SUCCESS)
+      if ((m = check_specification_function (e)) != MATCH_YES)
 	{
-	  m = gfc_intrinsic_func_interface (e, 0);
+	  if ((m = gfc_intrinsic_func_interface (e, 0)) != MATCH_YES)
+	    {
+	      gfc_error ("Function '%s' in initialization expression at %L "
+			 "must be an intrinsic or a specification function",
+			 e->symtree->n.sym->name, &e->where);
+	      break;
+	    }
 
-	  if (m == MATCH_NO)
-	    gfc_error ("Function '%s' in initialization expression at %L "
-		       "must be an intrinsic function",
-		       e->symtree->n.sym->name, &e->where);
+	  if ((m = check_conversion (e)) == MATCH_NO
+	      && (m = check_inquiry (e, 1)) == MATCH_NO
+	      && (m = check_null (e)) == MATCH_NO
+	      && (m = check_transformational (e)) == MATCH_NO
+	      && (m = check_elemental (e)) == MATCH_NO)
+	    {
+	      gfc_error ("Intrinsic function '%s' at %L is not permitted "
+			 "in an initialization expression",
+			 e->symtree->n.sym->name, &e->where);
+	      m = MATCH_ERROR;
+	    }
 
-	  if (m != MATCH_YES)
-	    t = FAILURE;
+	  /* Try to scalarize an elemental intrinsic function that has an
+	     array argument.  */
+	  isym = gfc_find_function (e->symtree->n.sym->name);
+	  if (isym && isym->elemental
+	      && e->value.function.actual->expr->expr_type == EXPR_ARRAY)
+	    {
+		if ((t = scalarize_intrinsic_call (e)) == SUCCESS)
+		break;
+	    }
 	}
 
+      if (m == MATCH_YES)
+	t = SUCCESS;
+
       break;
 
     case EXPR_VARIABLE:
@@ -1996,10 +2140,39 @@ check_init_expr (gfc_expr *e)
       if (gfc_in_match_data ())
 	break;
 
-      gfc_error ("Parameter '%s' at %L has not been declared or is "
-		 "a variable, which does not reduce to a constant "
-		 "expression", e->symtree->n.sym->name, &e->where);
       t = FAILURE;
+
+      if (e->symtree->n.sym->as)
+	{
+	  switch (e->symtree->n.sym->as->type)
+	    {
+	      case AS_ASSUMED_SIZE:
+		gfc_error ("assumed size array '%s' at %L is not permitted "
+			   "in an initialization expression",
+			   e->symtree->n.sym->name, &e->where);
+	      break;
+
+	      case AS_ASSUMED_SHAPE:
+		gfc_error ("assumed shape array '%s' at %L is not permitted "
+			   "in an initialization expression",
+			   e->symtree->n.sym->name, &e->where);
+	      break;
+
+	      case AS_DEFERRED:
+		gfc_error ("deferred array '%s' at %L is not permitted "
+			   "in an initialization expression",
+			   e->symtree->n.sym->name, &e->where);
+	      break;
+
+	      default:
+		gcc_unreachable();
+	  }
+	}
+      else
+	gfc_error ("Parameter '%s' at %L has not been declared or is "
+		   "a variable, which does not reduce to a constant "
+		   "expression", e->symtree->n.sym->name, &e->where);
+
       break;
 
     case EXPR_CONSTANT:
@@ -2078,7 +2251,7 @@ gfc_match_init_expr (gfc_expr **result)
 
   /* Not all inquiry functions are simplified to constant expressions
      so it is necessary to call check_inquiry again.  */ 
-  if (!gfc_is_constant_expr (expr) && check_inquiry (expr, 1) == FAILURE
+  if (!gfc_is_constant_expr (expr) && check_inquiry (expr, 1) != MATCH_YES
       && !gfc_in_match_data ())
     {
       gfc_error ("Initialization expression didn't reduce %C");
@@ -2161,7 +2334,7 @@ static try
 restricted_intrinsic (gfc_expr *e)
 {
   /* TODO: Check constraints on inquiry functions.  7.1.6.2 (7).  */
-  if (check_inquiry (e, 0) == SUCCESS)
+  if (check_inquiry (e, 0) == MATCH_YES)
     return SUCCESS;
 
   return restricted_args (e->value.function.actual);