gold won't build with gcc-9

	* symtab.h (Symbol::Symbol): Avoid -Wclass-memaccess warning.
diff --git a/gold/ChangeLog b/gold/ChangeLog
index f0d3ef9..2379536 100644
--- a/gold/ChangeLog
+++ b/gold/ChangeLog
@@ -1,3 +1,7 @@
+2018-12-05  Alan Modra  <amodra@gmail.com>
+
+	* symtab.h (Symbol::Symbol): Avoid -Wclass-memaccess warning.
+
 2018-12-03  Alexey Neyman  <stilor@att.net>
 
 	PR gold/23594
diff --git a/gold/symtab.h b/gold/symtab.h
index 089e156..16a2448 100644
--- a/gold/symtab.h
+++ b/gold/symtab.h
@@ -914,7 +914,7 @@
   // Instances of this class should always be created at a specific
   // size.
   Symbol()
-  { memset(this, 0, sizeof *this); }
+  { memset(static_cast<void*>(this), 0, sizeof *this); }
 
   // Initialize the general fields.
   void