m4: use AS_IF instead of ! builtin.

* m4/sanity.m4: Switch `if !` to AS_IF.

diff --git a/m4/sanity.m4 b/m4/sanity.m4
index 4abd18773c8bf5688049571262eb2f1a4fe59d1d..8887a0c98ca8301a53bbba73f4122040bc3f8082 100644 (file)
--- a/m4/sanity.m4
+++ b/m4/sanity.m4
@@ -131,10 +131,10 @@ fi
 # If we didn't sleep, we still need to ensure time stamps of config.status and
 # generated files are strictly newer.
 am_sleep_pid=
-if ! test -e conftest.file || grep 'slept: no' conftest.file >/dev/null 2>&1; then
+AS_IF([test -e conftest.file || grep 'slept: no' conftest.file >/dev/null 2>&1],, [dnl
   ( sleep $am_cv_filesystem_timestamp_resolution ) &
   am_sleep_pid=$!
-fi
+])
 AC_CONFIG_COMMANDS_PRE(
   [AC_MSG_CHECKING([that generated files are newer than configure])
    if test -n "$am_sleep_pid"; then