From d7a6e7464bb4e31db396074a1a4161acc933758b Mon Sep 17 00:00:00 2001
From: Charles Milette <charles.milette@gmail.com>
Date: Sun, 15 Dec 2019 17:40:45 -0500
Subject: [PATCH] Only enable feature when alias CTAD is available

---
 include/fmt/format.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/include/fmt/format.h b/include/fmt/format.h
index 465a2871..b76c1391 100644
--- a/include/fmt/format.h
+++ b/include/fmt/format.h
@@ -700,6 +700,7 @@ void basic_memory_buffer<T, SIZE, Allocator>::grow(std::size_t size) {
   if (old_data != store_) Allocator::deallocate(old_data, old_capacity);
 }
 
+#if defined(__cpp_deduction_guides) && __cpp_deduction_guides >= 201907L
 template <std::size_t SIZE = inline_buffer_size,
           typename Allocator = std::allocator<char>>
 using memory_buffer = basic_memory_buffer<char, SIZE, Allocator>;
@@ -707,6 +708,10 @@ using memory_buffer = basic_memory_buffer<char, SIZE, Allocator>;
 template <std::size_t SIZE = inline_buffer_size,
           typename Allocator = std::allocator<wchar_t>>
 using wmemory_buffer = basic_memory_buffer<wchar_t, SIZE, Allocator>;
+#else
+using memory_buffer = basic_memory_buffer<char>;
+using wmemory_buffer = basic_memory_buffer<wchar_t>;
+#endif // defined(__cpp_deduction_guides) && __cpp_deduction_guides >= 201907L
 
 /** A formatting error such as invalid format string. */
 FMT_CLASS_API