diff --git a/build/org.eclipse.cdt.managedbuilder.gnu.ui/plugin.properties b/build/org.eclipse.cdt.managedbuilder.gnu.ui/plugin.properties
index e9caf25062a..45ccc47f9c2 100644
--- a/build/org.eclipse.cdt.managedbuilder.gnu.ui/plugin.properties
+++ b/build/org.eclipse.cdt.managedbuilder.gnu.ui/plugin.properties
@@ -123,6 +123,7 @@ Option.Posix.Optimize.None=None (-O0)
 Option.Posix.Optimize.Optimize=Optimize (-O1)
 Option.Posix.Optimize.More=Optimize more (-O2)
 Option.Posix.Optimize.Most=Optimize most (-O3)
+Option.Posix.Optimize.Size=Optimize for size (-Os)
 Option.Posix.Optimize.Flags=Other optimization flags
 
 Option.Posix.DebugLevel=Debug Level
diff --git a/build/org.eclipse.cdt.managedbuilder.gnu.ui/plugin.xml b/build/org.eclipse.cdt.managedbuilder.gnu.ui/plugin.xml
index 1c405bebc63..8d43a117b99 100644
--- a/build/org.eclipse.cdt.managedbuilder.gnu.ui/plugin.xml
+++ b/build/org.eclipse.cdt.managedbuilder.gnu.ui/plugin.xml
@@ -1043,6 +1043,11 @@
 				  command="-O3"
 				  id="gnu.c.optimization.level.most">
 		  </enumeratedOptionValue>
+          <enumeratedOptionValue
+                  command="-Os"
+                  id="gnu.c.optimization.level.size"
+                  name="%Option.Posix.Optimize.Size">
+          </enumeratedOptionValue>
 		      <enablement 
               	type="CONTAINER_ATTRIBUTE" 
               	attribute="defaultValue" 
@@ -1337,6 +1342,11 @@
 				  command="-O3"
 				  id="gnu.cpp.compiler.optimization.level.most">
 		  </enumeratedOptionValue>
+          <enumeratedOptionValue
+                  command="-Os"
+                  id="gnu.cpp.compiler.optimization.level.size"
+                  name="%Option.Posix.Optimize.Size">
+          </enumeratedOptionValue>
 		      <enablement 
               	type="CONTAINER_ATTRIBUTE" 
               	attribute="value"