diff --git a/config.h.in b/config.h.in
index 1dfb8cf..6c364e9 100644
--- a/config.h.in
+++ b/config.h.in
@@ -1,5 +1,8 @@
 /* config.h.in.  Generated from configure.ac by autoheader.  */
 
+/* Define to 1 if you have the `m' library (-lm). */
+#undef HAVE_LIBM
+
 /* Name of package */
 #undef PACKAGE
 
diff --git a/configure.ac b/configure.ac
index b50a70b..306c9f2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -30,6 +30,8 @@ AC_PROG_CC
 
 # Configure dependency libs
 
+AC_CHECK_LIB([m],[lroundf])
+
 #   fftw3f
 deps_packages+=" fftw3f"