diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5a410783..136d7287 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,7 +24,7 @@ endif()
 #string(TOLOWER ${OPENJPEG_NAMESPACE} OPENJPEG_LIBRARY_NAME)
 set(OPENJPEG_LIBRARY_NAME openjp2)
 
-project(${OPENJPEG_NAMESPACE})
+project(${OPENJPEG_NAMESPACE} C)
 
 # Do full dependency headers.
 include_regular_expression("^.*$")
diff --git a/thirdparty/CMakeLists.txt b/thirdparty/CMakeLists.txt
index b0b229c8..ebdcd9d4 100644
--- a/thirdparty/CMakeLists.txt
+++ b/thirdparty/CMakeLists.txt
@@ -120,5 +120,6 @@ endif(BUILD_THIRDPARTY)
 
 #------------
 IF (WITH_ASTYLE)
+  enable_language(CXX)
   ADD_SUBDIRECTORY(astyle)
 ENDIF(WITH_ASTYLE)