Don't allow the left machine of <: to escape through the right machine via the

empty string.

git-svn-id: http://svn.complang.org/ragel/trunk@395 052ea7fc-9027-0410-9066-f65837a77df0

diff --git a/ragel/parsetree.cpp b/ragel/parsetree.cpp
index 6725378..c95921f 100644 (file)
--- a/ragel/parsetree.cpp
+++ b/ragel/parsetree.cpp
@@ -889,14 +889,14 @@ FsmAp *Term::walk( ParseData *pd, bool lastInSeq )
                        priorDescs[0].priority = 1;
                        rtnVal->allTransPrior( pd->curPriorOrd++, &priorDescs[0] );
 
-                       /* The right machine gets the lower priority.  Since
-                        * startTransPrior might unnecessarily increase the number of
-                        * states during the state machine construction process (due to
-                        * isolation), we use allTransPrior instead, which has the same
-                        * effect. */
+                       /* The right machine gets the lower priority. We cannot use
+                        * allTransPrior here in case the start state of the right machine
+                        * is final. It would allow the right machine thread to run along
+                        * with the left if just passing through the start state. Using
+                        * startFsmPrior prevents this. */
                        priorDescs[1].key = priorDescs[0].key;
                        priorDescs[1].priority = 0;
-                       rhs->allTransPrior( pd->curPriorOrd++, &priorDescs[1] );
+                       rhs->startFsmPrior( pd->curPriorOrd++, &priorDescs[1] );
 
                        /* Perform concatenation. */
                        rtnVal->concatOp( rhs );