From c16eb098d5a24234b9cc7e34bb3c49bb21e043f6 Mon Sep 17 00:00:00 2001
From: Kefu Chai <kchai@redhat.com>
Date: Fri, 25 May 2018 12:34:33 +0800
Subject: [PATCH] denc: specialize for denc(const T&, size_t&, uint64_t)

otherwise GCC complains that 'unsigned long int' is not a class or
namespace when trying to materialize is_const_iterator_v<>. not sure why
SFINAE does not work here, though.

Signed-off-by: Kefu Chai <kchai@redhat.com>
---
 src/include/denc.h | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/include/denc.h b/src/include/denc.h
index cd8a43360678a..f80f1a0c4c46d 100644
--- a/src/include/denc.h
+++ b/src/include/denc.h
@@ -243,14 +243,16 @@ using underlying_type_t = typename underlying_type<T>::type;
 }
 
 template<class It>
-struct is_const_iterator {
-  using pointer = typename It::pointer;
-  static constexpr bool value = std::is_const_v<std::remove_pointer_t<pointer>>;
-};
+struct is_const_iterator
+  : std::conditional_t<std::is_const_v<std::remove_pointer_t<typename It::pointer>>,
+		       std::true_type,
+		       std::false_type>
+{};
+template<>
+struct is_const_iterator<size_t> : std::false_type {};
 template<>
-struct is_const_iterator<buffer::list::contiguous_appender> {
+struct is_const_iterator<buffer::list::contiguous_appender> : std::false_type {
   // appender is used for *changing* the buffer
-  static constexpr bool value = false;
 };
 template<class It>
 inline constexpr bool is_const_iterator_v = is_const_iterator<It>::value;
-- 
2.39.5