diff --git a/src/ifcparse/IfcWrite.cpp b/src/ifcparse/IfcWrite.cpp
index fe5b8064c8..3d863f0c36 100644
--- a/src/ifcparse/IfcWrite.cpp
+++ b/src/ifcparse/IfcWrite.cpp
@@ -228,7 +228,7 @@ void IfcWritableEntity::setArgument(int i, Argument* a, IfcUtil::ArgumentType at
 		break;
 	case IfcUtil::Argument_EMPTY_AGGREGATE: 
 	case IfcUtil::Argument_AGGREGATE_OF_EMPTY_AGGREGATE: {
-		IfcUtil::ArgumentType t2 = IfcSchema::Type::GetAttributeType(type(), (unsigned) i);
+		IfcUtil::ArgumentType t2 = IfcSchema::Type::GetAttributeType(type(), (unsigned char) i);
 		this->setArgument(i, a, t2); }
 		break;
 	default:
diff --git a/src/ifcwrap/CMakeLists.txt b/src/ifcwrap/CMakeLists.txt
index 2c27340d43..4dea70ff1a 100644
--- a/src/ifcwrap/CMakeLists.txt
+++ b/src/ifcwrap/CMakeLists.txt
@@ -52,7 +52,8 @@ ENDIF()
 
 SET_SOURCE_FILES_PROPERTIES(IfcPython.i PROPERTIES CPLUSPLUS ON)
 SWIG_ADD_MODULE(ifcopenshell_wrapper python IfcPython.i)
-SWIG_LINK_LIBRARIES(ifcopenshell_wrapper ${IFCOPENSHELL_LIBRARIES} ${PYTHON_LIBRARIES} ${OPENCASCADE_LIBRARIES} ${ICU_LIBRARIES})
+SWIG_LINK_LIBRARIES(ifcopenshell_wrapper ${IFCOPENSHELL_LIBRARIES} ${PYTHON_LIBRARIES} ${OPENCASCADE_LIBRARIES}
+    ${ICU_LIBRARIES} ${Boost_LIBRARIES})
 if ((NOT WIN32) AND BUILD_SHARED_LIBS)
     SET_INSTALL_RPATHS(${SWIG_MODULE_ifcopenshell_wrapper_REAL_NAME} "${IFCDIRS};${OCC_LIBRARY_DIR};${ICU_LIBRARY_DIR}")
 endif()