[Bug 3291543] There was a crash if dchars removed all coordinates of a polygon.

3 files changed, 14 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 2729e5d..cb637a9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2011-04-22  Peter Spjuth  <peter.spjuth@gmail.com>
+
+	* generic/tkCanvPoly.c: [Bug 3291543] There was a crash if dchars
+	* tests/canvas.test:    removed all coordinates of a polygon.
+
 2011-04-21  Peter Spjuth  <peter.spjuth@gmail.com>
 
 	* doc/checkbutton.n: Document all variable options as global.
diff --git a/generic/tkCanvPoly.c b/generic/tkCanvPoly.c
index 798576b..96867a8 100644
--- a/generic/tkCanvPoly.c
+++ b/generic/tkCanvPoly.c
@@ -1187,6 +1187,7 @@ PolygonDeleteCoords(canvas, itemPtr, first, last)
 	polyPtr->numPoints = 0;
 	if(polyPtr->coordPtr != NULL) {
 	    ckfree((char *) polyPtr->coordPtr);
+	    polyPtr->coordPtr = NULL;
 	}
 	ComputePolygonBbox(canvas, polyPtr);
 	return;
diff --git a/tests/canvas.test b/tests/canvas.test
index ed470f9..f62eb2e 100644
--- a/tests/canvas.test
+++ b/tests/canvas.test
@@ -382,6 +382,14 @@ test canvas-11.2 {canvas poly overlap fill check, bug 226357} {
     .c itemconfig 1 -width 8
     lappend result [.c find over 45 50 45 50]; # outside poly
 } {1 1 {} 1 {} 1 1 {} 1 {} 1}
+test canvas-11.3 {canvas poly dchars, bug 3291543} {
+    # This would crash
+    destroy .c
+    pack [canvas .c]
+    .c create polygon 0 0 0 10 10 0
+    .c dchars 1 2 end
+    .c coords 1
+} {}
 
 test canvas-12.1 {canvas mm obj, patch SF-403327, 102471} {
     destroy .c