diff --git a/configure.in b/configure.in
index 174eb9b2..321b1f2b 100644
--- a/configure.in
+++ b/configure.in
@@ -1021,7 +1021,7 @@ AC_SUBST(BASE_THREAD_LIBS)
 AC_SUBST(WITH_THREADS)
 AC_SUBST(THREAD_CFLAGS)
 AC_SUBST(TEST_THREADS)
-AM_CONDITIONAL(THREADS_W32, test -n "$THREADS_WIN32")
+AM_CONDITIONAL([THREADS_W32],[test -n "$THREADS_W32"])
 
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