+
+dnl Check for /usr/bin/time and get full path.
+AC_PATH_PROG(TIME,time,no)
+if test "x$TIME" = "xno"; then
+ AC_MSG_ERROR(['time' command not found])
+fi
+
+dnl Check for diff and get full path.
+AC_PATH_PROG(DIFF,diff,no)
+if test "x$DIFF" = "xno"; then
+ AC_MSG_ERROR(['diff' command not found])
+fi
+AC_SUBST(DIFF)
+
+dnl Check for gprof (optional).
+AC_CHECK_PROG(GPROF,gprof,gprof,no)
+
+dnl Check for ocaml-bisect (optional) and --enable-coverage.
+AC_CHECK_PROG(BISECT_REPORT,bisect-report,bisect-report,no)
+AC_ARG_ENABLE([coverage],
+ [AS_HELP_STRING([--enable-coverage],
+ [add code coverage information (slow) @<:@default=no@:>@])],
+ [],
+ [enable_coverage=no])
+
+if test "x$enable_coverage" != "xno" -a "x$BISECT_REPORT" = "xno"; then
+ AC_MSG_ERROR([You must install ocaml-bisect package to get code coverage])
+fi
+AC_SUBST(enable_coverage)