diff --git a/ChangeLog b/ChangeLog
index b35f901a88..b7df89dca9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Wed Jun  3 21:14:20 2015  Tanaka Akira  <akr@fsij.org>
+
+	* ext/rbconfig/sizeof/extconf.rb: Check C99 standard integer types.
+
 Wed Jun  3 21:00:47 2015  Tanaka Akira  <akr@fsij.org>
 
 	* configure.in: Don't check __int128.
diff --git a/ext/rbconfig/sizeof/extconf.rb b/ext/rbconfig/sizeof/extconf.rb
index f4379b0bd5..66f7d77630 100644
--- a/ext/rbconfig/sizeof/extconf.rb
+++ b/ext/rbconfig/sizeof/extconf.rb
@@ -1,4 +1,23 @@
 $srcs = %w[sizes.c]
 $distcleanfiles.concat($srcs)
+check_sizeof('int8_t')
+check_sizeof('int16_t')
+check_sizeof('int32_t')
+check_sizeof('int64_t')
+check_sizeof('int_least8_t')
+check_sizeof('int_least16_t')
+check_sizeof('int_least32_t')
+check_sizeof('int_least64_t')
+check_sizeof('int_fast8_t')
+check_sizeof('int_fast16_t')
+check_sizeof('int_fast32_t')
+check_sizeof('int_fast64_t')
+check_sizeof('intptr_t')
+check_sizeof('intmax_t')
+check_sizeof('sig_atomic_t', %w[signal.h])
+check_sizeof('wchar_t')
+check_sizeof('wint_t', %w[wctype.h])
+check_sizeof('wctrans_t', %w[wctype.h])
+check_sizeof('wctype_t', %w[wctype.h])
 check_sizeof('__int128')
 create_makefile('rbconfig/sizeof')