dump_parse_tree (debug): Add verison for formal arglist.

2019-06-16  Thomas Koenig  <tkoenig@gcc.gnu.org>

    * dump_parse_tree (debug): Add verison for formal arglist.
    Do not crash when a gfc_expr is NULL.

From-SVN: r272353

gcc/fortran/ChangeLog

+2019-06-16  Thomas Koenig  <tkoenig@gcc.gnu.org>
+
+	* dump_parse_tree (debug): Add verison for formal arglist.
+	Do not crash when a gfc_expr is NULL.
+
 2019-06-15  Steven G. Kargl  <kargl@gcc.gnu.org>
 
 	* decl.c (gfc_match_derived_decl): Dummy argument cannot be a derived

gcc/fortran/dump-parse-tree.c

@@ -66,6 +66,19 @@ void debug (symbol_attribute *attr)
   dumpfile = tmp;
 }
 
+void debug (gfc_formal_arglist *formal)
+{
+  FILE *tmp = dumpfile;
+  dumpfile = stderr;
+  for (; formal; formal = formal->next)
+    {
+      fputc ('\n', dumpfile);
+      show_symbol (formal->sym);
+    }
+  fputc ('\n', dumpfile);
+  dumpfile = tmp;
+}
+
 void debug (symbol_attribute attr)
 {
   debug (&attr);
@@ -75,9 +88,15 @@ void debug (gfc_expr *e)
 {
   FILE *tmp = dumpfile;
   dumpfile = stderr;
-  show_expr (e);
-  fputc (' ', dumpfile);
-  show_typespec (&e->ts);
+  if (e != NULL)
+    {
+      show_expr (e);
+      fputc (' ', dumpfile);
+      show_typespec (&e->ts);
+    }
+  else
+    fputs ("() ", dumpfile);
+
   fputc ('\n', dumpfile);
   dumpfile = tmp;
 }