https://github.com/lpereira/hardinfo/pull/6

--- hardinfo-0.5.2_pre20120527/hardinfo/util.c
+++ hardinfo-0.5.2_pre20120527/hardinfo/util.c
@@ -1368,7 +1368,7 @@
 {
 	if (G_UNLIKELY(!_moreinfo)) {
 		DEBUG("moreinfo not initialized");
-		return;
+		return 0;
 	}
 	
 	if (prefix) {
--- hardinfo-0.5.2_pre20120527/CMakeLists.txt
+++ hardinfo-0.5.2_pre20120527/CMakeLists.txt
@@ -43,6 +43,8 @@
 
 message(STATUS "Building HardInfo for architecture: ${HARDINFO_OS}-${HARDINFO_ARCH}")
 
+add_definitions("-std=gnu89")
+
 include(FindPkgConfig)
 pkg_check_modules(GTK REQUIRED gtk+-2.0>=2.10 glib-2.0>=2.10 gthread-2.0>=2.10 gmodule-export-2.0>=2.10)
 pkg_check_modules(LIBSOUP libsoup-2.4>=2.24)