[libcxx-commits] [PATCH] D125586: Fix broken SFINAE in std::__copy for trivially copyable types.

[Daniel Cheng via Phabricator via libcxx-commits]

dcheng created this revision.
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dcheng requested review of this revision.
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With the broken SFINAE, std::copy will never use memmove, even for
trivially copyable types.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D125586

Files:
  libcxx/include/__algorithm/copy.h


Index: libcxx/include/__algorithm/copy.h
===================================================================
--- libcxx/include/__algorithm/copy.h
+++ libcxx/include/__algorithm/copy.h
@@ -80,19 +80,18 @@
 }
 
 template <class _InIter, class _Sent, class _OutIter,
-          __enable_if_t<is_copy_constructible<_InIter>::value
-                     && is_copy_constructible<_Sent>::value
-                     && is_copy_constructible<_OutIter>::value> >
-inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
-pair<_InIter, _OutIter> __copy(_InIter __first, _Sent __last, _OutIter __result) {
+          class __enable_if_t<is_copy_constructible<_InIter>::value && is_copy_constructible<_Sent>::value &&
+                              is_copy_constructible<_OutIter>::value> >
+inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 pair<_InIter, _OutIter> __copy(_InIter __first, _Sent __last,
+                                                                                          _OutIter __result) {
   auto __ret = std::__copy_impl(std::__unwrap_iter(__first), std::__unwrap_iter(__last), std::__unwrap_iter(__result));
   return std::make_pair(std::__rewrap_iter(__first, __ret.first), std::__rewrap_iter(__result, __ret.second));
 }
 
 template <class _InputIterator, class _OutputIterator>
-inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator
-copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result) {
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator copy(_InputIterator __first,
+                                                                                    _InputIterator __last,
+                                                                                    _OutputIterator __result) {
   return std::__copy(__first, __last, __result).second;
 }
 


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