diff --git a/configure.ac b/configure.ac
index abd465973..717fe6f4b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -124,7 +124,7 @@ AC_CHECK_HEADER([boost/regex.hpp],
 
 AC_LANG_POP([C++])
 
-PKG_CHECK_MODULES(LUMIERA_COMMON_LIBS, [sigc++-2.0 >= 2.0.18])
+PKG_CHECK_MODULES(LUMIERA_COMMON_LIBS, [sigc++-2.0 >= 2.0.17])
 
 ############## Internatinalization
 #GETTEXT_PACKAGE=gtk-lumiera
diff --git a/tests/backend/test-filemmap.c b/tests/backend/test-filemmap.c
index 17861cb85..7cae6f362 100644
--- a/tests/backend/test-filemmap.c
+++ b/tests/backend/test-filemmap.c
@@ -48,7 +48,9 @@ TEST ("mmap_semantic")
   int fd = open (",mmaptest", O_RDWR|O_CREAT, 0666);
   printf ("got fd %d\n", fd);
   printf ("error %s\n", strerror (errno));
-  ftruncate (fd, 8192);
+  int dummy = ftruncate (fd, 8192);
+  (void)dummy;
+  TODO ("handle error case better");
 
   void* addr = mmap (NULL,
                      8192,