Compiler refinement (edit 530): a line starting with "+else" within a ++ifdef clause will now be tagged as a syntax error. Normally, the compiler ignores the contents of ++ifdef clauses if the controlling condition is not met. But it is too easy to make a mistake like...
++ifdef SOME_SYMBOL
<some code>
+else
<some other code>
++endif
... assuming that one of the two sections of code is operative, when in fact unless SOME_SYMBOL was defined, none of the code would have been operative because "+else" was just ignored along with everything else between the ++ifdef and ++endif.
Note: this is the same as the 6.1.617 patch but has a different number here due to differences in the 6.0 and 6.1 compiler release structure.
