[tree-ssa] Merge results as of 2003-05-06

[law@redhat.com]

In message <wvlfznq6rsx.fsf@prospero.boston.redhat.com>, Jason Merrill writes:
 >On Wed, 07 May 2003 21:06:17 -0600, law@redhat.com wrote:
 >
 >> We can't eliminate BIND_EXPRs with empty bodies unless they also have no
 >> variables (see the thread regarding variables being used outside their
 >> scope :-)
 >
 >If the body is empty, how could the variables be interesting?
They can be used outside their scope right now.  In fact, that's the sole
reason why this hunk of code isn't installed into the tree-ssa branch:

          /* Similarly if the BIND_EXPR has no executable code, then
             we can eliminate the BIND_EXPR as any variables can never
             be used.  */
          else if (TREE_CODE (BIND_EXPR_BODY (*stmt_p)) == LABEL_EXPR
                   || IS_EMPTY_STMT (BIND_EXPR_BODY (*stmt_p)))
            *stmt = BIND_EXPR_BODY (*stmt_p);


Jeff