Fix formatting of bool with FMT_COMPILE and add more tests

include/fmt/format.h

@@ -3380,7 +3380,8 @@ inline std::string to_string(const T& value) {
 }
 template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
 inline std::string to_string(T value) {
-  char buffer[detail::digits10<T>() + 2];
+  // Buffer should be large enough to store the number or "false" (for bool).
+  char buffer[(std::max)(detail::digits10<T>() + 2, 5)];
   char* begin = buffer;
   char* end = detail::write<char>(begin, value);
   return std::string(begin, end);

test/compile-test.cc

@@ -144,8 +144,15 @@ TEST(CompileTest, EmptyFormatString) {
 }
 
 #ifdef __cpp_if_constexpr
-TEST(CompileTest, Basic) {
+TEST(CompileTest, FormatDefault) {
   EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42));
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42u));
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42ll));
+  EXPECT_EQ("42", fmt::format(FMT_COMPILE("{}"), 42ull));
+  EXPECT_EQ("true", fmt::format(FMT_COMPILE("{}"), true));
+  EXPECT_EQ("x", fmt::format(FMT_COMPILE("{}"), 'x'));
+  EXPECT_EQ("4.2", fmt::format(FMT_COMPILE("{}"), 4.2));
   EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), "foo"));
+  EXPECT_EQ("foo", fmt::format(FMT_COMPILE("{}"), std::string("foo")));
 }
 #endif