--- a/saslauthd/configure.in	2015-11-20 16:22:07.295862770 +0100
+++ b/saslauthd/configure.in	2015-11-20 16:23:35.581855882 +0100
@@ -164,30 +164,30 @@
 
 dnl Checks for which function macros exist
 AC_MSG_CHECKING(whether $CC implements __func__)
-AC_CACHE_VAL(have_func,
+AC_CACHE_VAL(ac_cv_have_func,
 [AC_TRY_LINK([#include <stdio.h>],[printf("%s", __func__);],
-have_func=yes,
-have_func=no)])
-AC_MSG_RESULT($have_func)
-if test "$have_func" = yes; then
+ac_cv_have_func=yes,
+ac_cv_have_func=no)])
+AC_MSG_RESULT($ac_cv_have_func)
+if test "$ac_cv_have_func" = yes; then
        AC_DEFINE(HAVE_FUNC,[],[Does the compiler understand __func__])
 else
        AC_MSG_CHECKING(whether $CC implements __PRETTY_FUNCTION__)
-       AC_CACHE_VAL(have_pretty_function,
+       AC_CACHE_VAL(ac_cv_have_pretty_function,
        [AC_TRY_LINK([#include <stdio.h>],[printf("%s", __PRETTY_FUNCTION__);],
-       have_pretty_function=yes,
-       have_pretty_function=no)])
-       AC_MSG_RESULT($have_pretty_function)
-       if test "$have_pretty_function" = yes; then
+       ac_cv_have_pretty_function=yes,
+       ac_cv_have_pretty_function=no)])
+       AC_MSG_RESULT($ac_cv_have_pretty_function)
+       if test "$ac_cv_have_pretty_function" = yes; then
                AC_DEFINE(HAVE_PRETTY_FUNCTION,[],[Does compiler understand __PRETTY_FUNCTION__])
        else
                AC_MSG_CHECKING(whether $CC implements __FUNCTION__)
-               AC_CACHE_VAL(have_function,
+               AC_CACHE_VAL(ac_cv_have_function,
                [AC_TRY_LINK([#include <stdio.h>],[printf("%s", __FUNCTION__);],
-               have_function=yes,
-               have_function=no)])
-               AC_MSG_RESULT($have_function)
-               if test "$have_function" = yes; then
+               ac_cv_have_function=yes,
+               ac_cv_have_function=no)])
+               AC_MSG_RESULT($ac_cv_have_function)
+               if test "$ac_cv_have_function" = yes; then
                        AC_DEFINE(HAVE_FUNCTION,[],[Does compiler understand __FUNCTION__])
                fi
        fi