Another bug fix.  Again, for constant propagation.  This time, related to update bytecode.
Another bug fix.  Again, for constant propagation.  This time, related to update bytecode.

Whiley/WhileyCompiler,hjwylde/whiley-compiler,hjwylde/whiley-compiler,hjwylde/whiley-compiler,hjwylde/whiley-compiler,hjwylde/whiley-compiler