diff --git a/adm/genproj.tcl b/adm/genproj.tcl
index 29dacf6055..04f9c20f91 100644
--- a/adm/genproj.tcl
+++ b/adm/genproj.tcl
@@ -2536,6 +2536,7 @@ proc osutils:cbp { theCmpl theOutDir theProjName thePlatform theSrcFiles theLibs
       lappend aCmplFlags "-DOCC_CONVERT_SIGNALS"
     }
     lappend aCmplFlags   "-Wall"
+    lappend aCmplFlags   "-Wextra"
     lappend aCmplFlags   "-fexceptions"
   }
   lappend aCmplFlagsRelease "-DNDEBUG"
diff --git a/adm/qmake/OccCppConfig.pri b/adm/qmake/OccCppConfig.pri
index 39b6fd004b..985d1051ce 100644
--- a/adm/qmake/OccCppConfig.pri
+++ b/adm/qmake/OccCppConfig.pri
@@ -13,8 +13,8 @@ OccGitRoot = $$_PRO_FILE_PWD_/../../../..
 
 # Define compilation flags
 CONFIG += warn_on
-QMAKE_CFLAGS_WARN_ON   = -Wall
-QMAKE_CXXFLAGS_WARN_ON = -Wall
+QMAKE_CFLAGS_WARN_ON   = -Wall -Wextra
+QMAKE_CXXFLAGS_WARN_ON = -Wall -Wextra
 win32 {
   QMAKE_CFLAGS_WARN_ON   = -W4
   QMAKE_CXXFLAGS_WARN_ON = -W4