diff --git a/org/hlacerti/build-certi.sh b/org/hlacerti/build-certi.sh
index 46904ac2270..f26f8e3d14f 100755
--- a/org/hlacerti/build-certi.sh
+++ b/org/hlacerti/build-certi.sh
@@ -27,6 +27,17 @@ fi
 CERTI_SRC=$SRC/certi-4.0.0
 if [ ! -f $CERTI_SRC ]; then
     git clone -b br_jbch_4.0.0 https://git.savannah.nongnu.org/git/certi.git $CERTI_SRC
+
+    echo "Patching $CERTI_SRC/CMakeLists.txt by moving a double quote and avoiding \"clang: error: no such file or directory: ';-flat_namespace'\" "
+    echo "See https://savannah.nongnu.org/bugs/index.php?53964"
+
+    sed -e 's/SET (CMAKE_SHARED_LINKER_FLAGS \${CMAKE_SHARED_LINKER_FLAGS_INIT} "-flat_namespace -undefined suppress"/SET (CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS_INIT} -flat_namespace -undefined suppress"/' \
+        -e 's/SET (CMAKE_MODULE_LINKER_FLAGS \${CMAKE_MODULE_LINKER_FLAGS_INIT} "-flat_namespace -undefined suppress"/SET (CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS_INIT} -flat_namespace -undefined suppress"/' \
+        $CERTI_SRC/CMakeLists.txt > $CERTI_SRC/CMakeLists.txt.tmp
+
+    diff $CERTI_SRC/CMakeLists.txt $CERTI_SRC/CMakeLists.txt.tmp
+    cp $CERTI_SRC/CMakeLists.txt.tmp  $CERTI_SRC/CMakeLists.txt
+    echo ""
 fi
 
 OS=`uname -s`
@@ -48,6 +59,7 @@ case $OS in
         sed 's/#include <features.h>//' $CERTI_SRC/libHLA/SemaphorePosix.hh > $CERTI_SRC/libHLA/SemaphorePosix.hh.tmp 
         diff $CERTI_SRC/libHLA/SemaphorePosix.hh $CERTI_SRC/libHLA/SemaphorePosix.hh.tmp 
         mv $CERTI_SRC/libHLA/SemaphorePosix.hh.tmp $CERTI_SRC/libHLA/SemaphorePosix.hh
+        echo ""
         ;;
     *)
       echo "You may need to install cmake, flex and bison"