-diff -pU3 a/configure b/configure
---- a/configure 2017-09-14 21:52:19.000000000 +0900
-+++ b/configure 2017-09-15 07:03:12.000000000 +0900
-@@ -10614,6 +10614,7 @@ fi
- ac_res=$ac_cv_search___gmpz_init
- if test "$ac_res" != no; then :
- test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
-+ $as_echo "#define HAVE_LIBGMP 1" >>confdefs.h
-
- fi
-
-@@ -10683,6 +10684,7 @@ fi
- ac_res=$ac_cv_search_malloc_conf
- if test "$ac_res" != no; then :
- test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
-+ $as_echo "#define HAVE_LIBJEMALLOC 1" >>confdefs.h
-
- else
- with_jemalloc=no
-diff -pU3 a/configure.in b/configure.in
---- a/configure.in 2017-08-04 23:39:29.000000000 +0900
-+++ b/configure.in 2017-09-15 07:20:40.000000000 +0900
-@@ -1403,13 +1403,15 @@ AC_ARG_WITH([gmp],
- AS_IF([test "x$with_gmp" != xno],
- [AC_CHECK_HEADERS(gmp.h)
- AS_IF([test "x$ac_cv_header_gmp_h" != xno],
-- AC_SEARCH_LIBS([__gmpz_init], [gmp]))])
-+ AC_SEARCH_LIBS([__gmpz_init], [gmp],
-+ [AC_DEFINE(HAVE_LIBGMP, 1)]))])
-
- AC_ARG_WITH([jemalloc],
- [AS_HELP_STRING([--with-jemalloc],[use jemalloc allocator])],
- [with_jemalloc=$withval], [with_jemalloc=no])
- AS_IF([test "x$with_jemalloc" = xyes],[
-- AC_SEARCH_LIBS([malloc_conf], [jemalloc], [], [with_jemalloc=no])
-+ AC_SEARCH_LIBS([malloc_conf], [jemalloc],
-+ [AC_DEFINE(HAVE_LIBJEMALLOC, 1)], [with_jemalloc=no])
- AC_CHECK_HEADER(jemalloc/jemalloc.h, [
- AC_DEFINE(RUBY_ALTERNATIVE_MALLOC_HEADER, [<jemalloc/jemalloc.h>])
- ])