diff --git a/include/fmt/core.h b/include/fmt/core.h
index 467fdb86..13a0edf2 100644
--- a/include/fmt/core.h
+++ b/include/fmt/core.h
@@ -2948,7 +2948,10 @@ class format_string_checker {
       basic_string_view<Char> format_str, ErrorHandler eh)
       : context_(format_str, num_args, types_, eh),
         parse_funcs_{&parse_format_specs<Args, parse_context_type>...},
-        types_{type_constant<Args, char>::value...} {}
+        types_{
+            mapped_type_constant<Args,
+                                 basic_format_context<Char*, Char>>::value...} {
+  }
 
   FMT_CONSTEXPR void on_text(const Char*, const Char*) {}
 
diff --git a/test/format-test.cc b/test/format-test.cc
index 5d8f19f3..f3bdb464 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -895,6 +895,7 @@ TEST(format_test, runtime_width) {
             fmt::format("{0:{1}}", reinterpret_cast<void*>(0xcafe), 10));
   EXPECT_EQ("x          ", fmt::format("{0:{1}}", 'x', 11));
   EXPECT_EQ("str         ", fmt::format("{0:{1}}", "str", 12));
+  EXPECT_EQ(fmt::format("{:{}}", 42, short(4)), "  42");
 }
 
 TEST(format_test, precision) {