Index: trunk/ppStack/src/ppStackMatch.c
===================================================================
--- trunk/ppStack/src/ppStackMatch.c	(revision 26218)
+++ trunk/ppStack/src/ppStackMatch.c	(revision 26454)
@@ -344,4 +344,5 @@
                                                        footprint); // Filtered list of sources
 
+            bool oldThreads = pmReadoutFakeThreads(true); // Old threading state
             if (!pmReadoutFakeFromSources(fake, readout->image->numCols, readout->image->numRows,
                                           stampSources, SOURCE_MASK, NULL, NULL, options->psf,
@@ -353,4 +354,5 @@
                 return false;
             }
+            pmReadoutFakeThreads(oldThreads);
 
             fake->mask = psImageCopy(NULL, readout->mask, PS_TYPE_IMAGE_MASK);