[Bug] Scanner does not clean zzFin appropriately [sf#118]

[lsf37]

*Reported by anonymous on 2011-11-10 20:40 UTC
I think, there is a bug on the line 1207 of the Emitter.java
Instead of " println(" if ((zzAttrL[zzFState] & 1) == 1) { zzFinL[zzFPos] = true; } ");"
it should read " println(" zzFinL[zzFPos] = ((zzAttrL[zzFState] & 1) == 1;");"

Otherwise, zzFin buffer is not cleared correctly (it is reused, but in the current code elements are never reset to false. See the patch attached.

[lsf37]

*Commented by anonymous on 2011-11-10 20:40 UTC
patch

[lsf37]

*Commented by anonymous on 2011-11-10 20:40 UTC
patch

[lsf37]

Commented by steve_rowe on 2013-10-11 08:55 UTC
Is this related to http://sourceforge.net/p/jflex/bugs/110/ ?

[lsf37]

Commented by steve_rowe on 2013-10-11 08:55 UTC
Is this related to http://sourceforge.net/p/jflex/bugs/110/ ?

[lsf37]

Commented by steve_rowe on 2013-12-21 23:12 UTC
I committed a fix in r723.

The patch for Emitter.java was a bit more involved though, since zzFin wasn't being fully updated with the original patch on this issue - here's what I committed:

@@ -1212,11 +1212,14 @@
         println("            if (zzFin.length <= zzBufferL.length) { zzFin = new boolean[zzBufferL.length+1]; }");
         println("            boolean zzFinL[] = zzFin;");
         println("            while (zzFState != -1 && zzFPos < zzMarkedPos) {");
-        println("              if ((zzAttrL[zzFState] & 1) == 1) { zzFinL[zzFPos] = true; } ");
+        println("              zzFinL[zzFPos] = ((zzAttrL[zzFState] & 1) == 1);");
         println("              zzInput = zzBufferL[zzFPos++];");
         println("              zzFState = zzTransL[ zzRowMapL[zzFState] + zzCMapL[zzInput] ];");
         println("            }");
-        println("            if (zzFState != -1 && (zzAttrL[zzFState] & 1) == 1) { zzFinL[zzFPos] = true; } ");
+        println("            if (zzFState != -1) { zzFinL[zzFPos++] = ((zzAttrL[zzFState] & 1) == 1); } ");
+        println("            while (zzFPos <= zzMarkedPos) {");
+        println("              zzFinL[zzFPos++] = false;");
+        println("            }");
         println();                
         println("            zzFState = "+dfa.entryState[action.getEntryState()+1]+";");
         println("            zzFPos = zzMarkedPos;");

I also added a new test case named genlook2 that failed without the above patch and succeeded with it.

[lsf37]

Commented by steve_rowe on 2013-12-21 23:12 UTC
I committed a fix in r723.

The patch for Emitter.java was a bit more involved though, since zzFin wasn't being fully updated with the original patch on this issue - here's what I committed:

@@ -1212,11 +1212,14 @@
         println("            if (zzFin.length <= zzBufferL.length) { zzFin = new boolean[zzBufferL.length+1]; }");
         println("            boolean zzFinL[] = zzFin;");
         println("            while (zzFState != -1 && zzFPos < zzMarkedPos) {");
-        println("              if ((zzAttrL[zzFState] & 1) == 1) { zzFinL[zzFPos] = true; } ");
+        println("              zzFinL[zzFPos] = ((zzAttrL[zzFState] & 1) == 1);");
         println("              zzInput = zzBufferL[zzFPos++];");
         println("              zzFState = zzTransL[ zzRowMapL[zzFState] + zzCMapL[zzInput] ];");
         println("            }");
-        println("            if (zzFState != -1 && (zzAttrL[zzFState] & 1) == 1) { zzFinL[zzFPos] = true; } ");
+        println("            if (zzFState != -1) { zzFinL[zzFPos++] = ((zzAttrL[zzFState] & 1) == 1); } ");
+        println("            while (zzFPos <= zzMarkedPos) {");
+        println("              zzFinL[zzFPos++] = false;");
+        println("            }");
         println();                
         println("            zzFState = "+dfa.entryState[action.getEntryState()+1]+";");
         println("            zzFPos = zzMarkedPos;");

I also added a new test case named genlook2 that failed without the above patch and succeeded with it.

[lsf37]

Updated by lsf37 on 2014-01-16 06:47 UTC

• status: open --> open-fixed
• Group: --> jflex bug

[lsf37]

Updated by lsf37 on 2014-01-16 06:47 UTC

• status: open --> open-fixed
• Group: --> jflex bug

[lsf37]

Updated by lsf37 on 2014-03-01 00:21 UTC

• status: open-fixed --> closed

[lsf37]

Updated by lsf37 on 2014-03-01 00:21 UTC

• status: open-fixed --> closed