MeshTools: fix an OOB access in tipsify().

doc/changelog.dox

@@ -188,6 +188,8 @@ See also:
 -   Calling @ref Platform::Sdl2Application::setSwapInterval() with @cpp 0 @ce
     caused @ref Platform::Sdl2Application::setMinimalLoopPeriod() "setMinimalLoopPeriod()"
     to be ignored even though Vsync was in fact not enabled.
+-   Fixed an otherwise harmless OOB access in @ref MeshTools::tipsify() that
+    could trigger ASan or debug iterator errors
 
 @subsection changelog-latest-deprecated Deprecated APIs
 

src/Magnum/MeshTools/Tipsify.cpp

@@ -57,7 +57,9 @@ void tipsify(std::vector<UnsignedInt>& indices, const UnsignedInt vertexCount, c
         std::vector<UnsignedInt> candidates;
 
         /* For all neighbors of fanning vertex */
-        for(UnsignedInt ti = neighborOffset[fanningVertex], t = neighbors[ti]; ti != neighborOffset[fanningVertex+1]; t = neighbors[++ti]) {
+        for(UnsignedInt ti = neighborOffset[fanningVertex]; ti != neighborOffset[fanningVertex+1]; ++ti) {
+            const UnsignedInt t = neighbors[ti];
+
             /* Continue if already emitted */
             if(emitted[t]) continue;
             emitted[t] = true;