Use = instead of == as operator to test
diff --git a/configure b/configure
index 6bc1c4e..1d538e4 100755
--- a/configure
+++ b/configure
@@ -18884,7 +18884,7 @@
 
   # wchar_t is only usable if it maps to an unsigned type
   if test "$unicode_size" = "$ac_cv_sizeof_wchar_t" \
-          -a "$ac_cv_wchar_t_signed" == "no"
+          -a "$ac_cv_wchar_t_signed" = "no"
   then
     PY_UNICODE_TYPE="wchar_t"