diff --git a/libs/spandsp/configure.ac b/libs/spandsp/configure.ac
index 412526fb0f..c2d9019274 100644
--- a/libs/spandsp/configure.ac
+++ b/libs/spandsp/configure.ac
@@ -204,9 +204,11 @@ AC_CHECK_HEADERS([strings.h])
 AC_CHECK_HEADERS([malloc.h])
 
 case "$host" in
+    *dragonfly*)
+    ;;
     *freebsd*)
     ;;
-    *dragonfly*)
+    *netbsd*)
     ;;
     *)
     AC_CHECK_HEADERS([tgmath.h], [INSERT_TGMATH_HEADER="#include <tgmath.h>"])