diff --git a/include/fmt/format.h b/include/fmt/format.h
index b8b64a30f02c..eddde2676e79 100644
--- a/include/fmt/format.h
+++ b/include/fmt/format.h
@@ -1174,8 +1174,8 @@ template <typename T = void> struct null {};
 template <typename Char> struct fill_t {
  private:
   enum { max_size = 4 };
-  Char data_[max_size];
-  unsigned char size_;
+  Char data_[max_size] = {Char(' '), Char(0), Char(0), Char(0)};
+  unsigned char size_ = 1;
 
  public:
   FMT_CONSTEXPR void operator=(basic_string_view<Char> s) {
@@ -1195,13 +1195,6 @@ template <typename Char> struct fill_t {
   FMT_CONSTEXPR const Char& operator[](size_t index) const {
     return data_[index];
   }
-
-  static FMT_CONSTEXPR fill_t<Char> make() {
-    auto fill = fill_t<Char>();
-    fill[0] = Char(' ');
-    fill.size_ = 1;
-    return fill;
-  }
 };
 }  // namespace detail
 
@@ -1233,8 +1226,7 @@ template <typename Char> struct basic_format_specs {
         type(0),
         align(align::none),
         sign(sign::none),
-        alt(false),
-        fill(detail::fill_t<Char>::make()) {}
+        alt(false) {}
 };
 
 using format_specs = basic_format_specs<char>;
diff --git a/test/format-test.cc b/test/format-test.cc
index ac1a96bb8c28..235058a3824e 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -355,22 +355,20 @@ TEST(MemoryBufferTest, ExceptionInDeallocate) {
 }
 
 template <typename Allocator, size_t MaxSize>
-class allocator_max_size: public Allocator {
+class allocator_max_size : public Allocator {
  public:
   using typename Allocator::value_type;
-  size_t max_size() const FMT_NOEXCEPT {
-    return MaxSize;
-  }
+  size_t max_size() const FMT_NOEXCEPT { return MaxSize; }
   value_type* allocate(size_t n) {
     if (n > max_size()) {
       throw std::length_error("size > max_size");
     }
     return std::allocator_traits<Allocator>::allocate(
-      *static_cast<Allocator *>(this), n);
+        *static_cast<Allocator*>(this), n);
   }
   void deallocate(value_type* p, size_t n) {
-    std::allocator_traits<Allocator>::deallocate(
-      *static_cast<Allocator *>(this), p, n);
+    std::allocator_traits<Allocator>::deallocate(*static_cast<Allocator*>(this),
+                                                 p, n);
   }
 };
 
@@ -383,7 +381,7 @@ TEST(MemoryBufferTest, AllocatorMaxSize) {
   try {
     // new_capacity = 128 + 128/2 = 192 > 160
     buffer.resize(160);
-  } catch (const std::exception &) {
+  } catch (const std::exception&) {
     throws_on_resize = true;
   }
   EXPECT_FALSE(throws_on_resize);
@@ -395,7 +393,7 @@ TEST(MemoryBufferTest, AllocatorMaxSizeOverflow) {
   bool throws_on_resize = false;
   try {
     buffer.resize(161);
-  } catch (const std::exception &) {
+  } catch (const std::exception&) {
     throws_on_resize = true;
   }
   EXPECT_TRUE(throws_on_resize);
@@ -2470,17 +2468,17 @@ TEST(FormatTest, CharTraitsIsNotAmbiguous) {
 #endif
 }
 
+#if __cplusplus > 201103L
 struct custom_char {
   int value;
   custom_char() = default;
 
-  template <typename T> custom_char(T val) : value(static_cast<int>(val)) {}
+  template <typename T>
+  constexpr custom_char(T val) : value(static_cast<int>(val)) {}
 
   operator int() const { return value; }
 };
 
-int to_ascii(custom_char c) { return c; }
-
 FMT_BEGIN_NAMESPACE
 template <> struct is_char<custom_char> : std::true_type {};
 FMT_END_NAMESPACE
@@ -2491,6 +2489,7 @@ TEST(FormatTest, FormatCustomChar) {
   EXPECT_EQ(result.size(), 1);
   EXPECT_EQ(result[0], custom_char('x'));
 }
+#endif
 
 // Convert a char8_t string to std::string. Otherwise GTest will insist on
 // inserting `char8_t` NTBS into a `char` stream which is disabled by P1423.