In method.cpp, there is one (safe) memcpy call that results in a dynamic-class-memaccess warning which causes compilation failure on recent versions of Xcode. We will fix this warning as part of our toolchain upgrade effort.

This is a partial backport of Paul Hohensee's massive cleanup [0] of Xcode warnings. A complete backport of that chnageset is well beyond the scope of our toolchain upgrade work. But we do want to clean up as many warnings as we can with minimal risk.

[0] http://hg.openjdk.java.net/jdk10/jdk10/hotspot/rev/c044f8d03932