Issue #471: always create directories with mode 0755, regardless of umask.

CMakeLists.txt

@@ -392,6 +392,17 @@ target_include_directories(${PROJECT_NAME}
         $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
 )
 
+# Always create new install dirs with 0755 permissions, regardless of umask
+set(CMAKE_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS
+	OWNER_READ
+	OWNER_WRITE
+	OWNER_EXECUTE
+	GROUP_READ
+	GROUP_EXECUTE
+	WORLD_READ
+	WORLD_EXECUTE
+   )
+
 install(TARGETS ${PROJECT_NAME}
     EXPORT ${PROJECT_NAME}-targets
     RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}