--- m4/threadlib.m4.orig	2020-06-03 23:04:44.000000000 +1000
+++ m4/threadlib.m4	2020-07-31 00:11:57.553015000 +1000
@@ -70,7 +70,7 @@
     # need special flags to disable these optimizations. For example, the
     # definition of 'errno' in <errno.h>.
     case "$host_os" in
-      aix* | freebsd*) CPPFLAGS="$CPPFLAGS -D_THREAD_SAFE" ;;
+      aix* | bsdsunix* | freebsd*) CPPFLAGS="$CPPFLAGS -D_THREAD_SAFE" ;;
       solaris*) CPPFLAGS="$CPPFLAGS -D_REENTRANT" ;;
     esac
     gl_anythreadlib_early_done=done
@@ -126,7 +126,7 @@
      case "$gl_cv_have_weak" in
        *yes)
          case "$host_os" in
-           freebsd* | dragonfly*)
+           bsdsunix* | freebsd* | dragonfly*)
              : > conftest1.c
              $CC $CPPFLAGS $CFLAGS $LDFLAGS -fPIC -shared -o libempty.so conftest1.c -lpthread >&AS_MESSAGE_LOG_FD 2>&1
              cat <<EOF > conftest2.c