Tweak the code to make it more reusable.

[gnulib.git] / m4 / stdbool.m4

diff --git a/m4/stdbool.m4 b/m4/stdbool.m4
index 922a002..dcb5793 100644 (file)
--- a/m4/stdbool.m4
+++ b/m4/stdbool.m4
@@ -76,7 +76,8 @@ AC_DEFUN([AC_HEADER_STDBOOL],
          char p[-1 - (_Bool) 0 < 0 && -1 - (bool) 0 < 0 ? 1 : -1];
        ],
        [
-         return (!a + !b + !c + !d + !e + !f + !g + !h + !i + !j + !k + !l
+         /* Refer to every declared value, to avoid compiler optimizations.  */
+         return (!a + !b + !c + !d + !e + !f + !g + !h + !i + !!j + !k + !!l
                  + !m + !n + !o + !p);
        ],
        [ac_cv_header_stdbool_h=yes],