[PATCH] Restore enable_if lost during original import of pstl

[Thomas Rodgers]

        * include/pstl/glue_numeric_defs.h: Restore enable_if lost during 
original
        import of pstl.
        * include/pstl/glue_numeric_impl.h: Likewise.
---
 libstdc++-v3/include/pstl/glue_numeric_defs.h | 2 +-
 libstdc++-v3/include/pstl/glue_numeric_impl.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/libstdc++-v3/include/pstl/glue_numeric_defs.h 
b/libstdc++-v3/include/pstl/glue_numeric_defs.h
index cc5a94e801a..78df1703079 100644
--- a/libstdc++-v3/include/pstl/glue_numeric_defs.h
+++ b/libstdc++-v3/include/pstl/glue_numeric_defs.h
@@ -55,7 +55,7 @@ exclusive_scan(_ExecutionPolicy&& __exec, _ForwardIterator1 
__first, _ForwardIte
                _ForwardIterator2 __result, _Tp __init);
 
 template <class _ExecutionPolicy, class _ForwardIterator1, class 
_ForwardIterator2, class _Tp, class _BinaryOperation>
-_ForwardIterator2
+__pstl::__internal::__enable_if_execution_policy<_ExecutionPolicy, 
_ForwardIterator2>
 exclusive_scan(_ExecutionPolicy&& __exec, _ForwardIterator1 __first, 
_ForwardIterator1 __last,
                _ForwardIterator2 __result, _Tp __init, _BinaryOperation 
__binary_op);
 
diff --git a/libstdc++-v3/include/pstl/glue_numeric_impl.h 
b/libstdc++-v3/include/pstl/glue_numeric_impl.h
index b1786fd387e..d5acbac5561 100644
--- a/libstdc++-v3/include/pstl/glue_numeric_impl.h
+++ b/libstdc++-v3/include/pstl/glue_numeric_impl.h
@@ -100,7 +100,7 @@ exclusive_scan(_ExecutionPolicy&& __exec, _ForwardIterator1 
__first, _ForwardIte
 }
 
 template <class _ExecutionPolicy, class _ForwardIterator1, class 
_ForwardIterator2, class _Tp, class _BinaryOperation>
-_ForwardIterator2
+__pstl::__internal::__enable_if_execution_policy<_ExecutionPolicy, 
_ForwardIterator2>
 exclusive_scan(_ExecutionPolicy&& __exec, _ForwardIterator1 __first, 
_ForwardIterator1 __last,
                _ForwardIterator2 __result, _Tp __init, _BinaryOperation 
__binary_op)
 {
-- 
2.21.0