diff --git a/Documentation/doc/scripts/process_doc.sh b/Documentation/doc/scripts/process_doc.sh
index 14db7216f36..3486ada48f5 100644
--- a/Documentation/doc/scripts/process_doc.sh
+++ b/Documentation/doc/scripts/process_doc.sh
@@ -20,7 +20,9 @@ DOXYGEN_2=$($PATH_TO_1_9_6 --version)
 
 DO_COMPARE=TRUE
 PATH_TO_SCRIPTS=${PWD}
+NB_CORES="$(nproc)"
 
+set +e
 #######################################
 ## download and build doxygen_master ##
  #######################################