diff --git a/configure b/configure
index 4cef321d9d..a273a93377 100755
--- a/configure
+++ b/configure
@@ -790,7 +790,7 @@ SunOS)
 ;;
 Haiku)
   haiku="yes"
-  QEMU_CFLAGS="-DB_USE_POSITIVE_POSIX_ERRORS -DBSD_SOURCE $QEMU_CFLAGS"
+  QEMU_CFLAGS="-DB_USE_POSITIVE_POSIX_ERRORS -D_BSD_SOURCE $QEMU_CFLAGS"
 ;;
 Linux)
   audio_drv_list="try-pa oss"