diff --git a/include/boost/unordered/detail/foa/concurrent_table.hpp b/include/boost/unordered/detail/foa/concurrent_table.hpp
index 722baf47..54341396 100644
--- a/include/boost/unordered/detail/foa/concurrent_table.hpp
+++ b/include/boost/unordered/detail/foa/concurrent_table.hpp
@@ -126,7 +126,7 @@ template<typename Mutex>
 class shared_lock
 {
 public:
-  shared_lock(Mutex& m_)noexcept:m{m_}{m.lock_shared();}
+  shared_lock(Mutex& m_)noexcept:m(m_){m.lock_shared();}
   ~shared_lock()noexcept{if(owns)m.unlock_shared();}
 
   /* not used but VS in pre-C++17 mode needs to see it for RVO */
@@ -148,7 +148,7 @@ template<typename Mutex>
 class lock_guard
 {
 public:
-  lock_guard(Mutex& m_)noexcept:m{m_}{m.lock();}
+  lock_guard(Mutex& m_)noexcept:m(m_){m.lock();}
   ~lock_guard()noexcept{m.unlock();}
 
   /* not used but VS in pre-C++17 mode needs to see it for RVO */
@@ -1029,7 +1029,7 @@ private:
     erase_on_exit(
       concurrent_table& x_,
       group_type* pg_,unsigned int pos_,element_type* p_):
-      x{x_},pg{pg_},pos{pos_},p{p_}{}
+      x(x_),pg(pg_),pos(pos_),p(p_){}
     ~erase_on_exit(){if(!rollback_)x.super::erase(pg,pos,p);}
 
     void rollback(){rollback_=true;}
@@ -1283,7 +1283,7 @@ private:
 
   struct reserve_size
   {
-    reserve_size(concurrent_table& x_):x{x_}
+    reserve_size(concurrent_table& x_):x(x_)
     {
       size_=++x.size_ctrl.size;
     }
diff --git a/include/boost/unordered/detail/foa/core.hpp b/include/boost/unordered/detail/foa/core.hpp
index 7842363e..c856c855 100644
--- a/include/boost/unordered/detail/foa/core.hpp
+++ b/include/boost/unordered/detail/foa/core.hpp
@@ -1043,7 +1043,13 @@ struct table_arrays
     initialize_groups(
       arrays.groups(),groups_size,
       std::integral_constant<
-        bool,std::is_trivially_constructible<group_type>::value
+        bool,
+#if BOOST_WORKAROUND(BOOST_LIBSTDCXX_VERSION,<50000)
+      /* std::is_trivially_default_constructible not provided */
+      std::has_trivial_default_constructor<group_type>::value
+#else
+      std::is_trivially_default_constructible<group_type>::value
+#endif 
       >{});
     arrays.groups()[groups_size-1].set_sentinel();
   }
@@ -2016,7 +2022,14 @@ private:
     copy_elements_array_from(
       x,
       std::integral_constant<
-        bool,std::is_trivially_copy_constructible<element_type>::value
+        bool,
+#if BOOST_WORKAROUND(BOOST_LIBSTDCXX_VERSION,<50000)
+        /* std::is_trivially_copy_constructible not provided */
+        std::is_copy_constructible<element_type>::value&&
+        std::has_trivial_copy_constructor<element_type>::value
+#else
+        std::is_trivially_copy_constructible<element_type>::value
+#endif
         &&(
           is_std_allocator<Allocator>::value||
           !alloc_has_construct<Allocator,value_type*,const value_type&>::value)
@@ -2060,7 +2073,13 @@ private:
 
   void copy_groups_array_from(const table_core& x) {
     copy_groups_array_from(x, std::integral_constant<bool,
+#if BOOST_WORKAROUND(BOOST_LIBSTDCXX_VERSION,<50000)
+      /* std::is_trivially_copy_assignable not provided */
+      std::is_copy_assignable<group_type>::value&&
+      std::has_trivial_copy_assign<group_type>::value
+#else
       std::is_trivially_copy_assignable<group_type>::value
+#endif
       >{}
     );
   }
diff --git a/include/boost/unordered/detail/foa/table.hpp b/include/boost/unordered/detail/foa/table.hpp
index 78cfa3b1..7e14bc75 100644
--- a/include/boost/unordered/detail/foa/table.hpp
+++ b/include/boost/unordered/detail/foa/table.hpp
@@ -106,7 +106,7 @@ public:
   using element_type=
     typename std::conditional<Const,value_type const,value_type>::type;
 
-  table_iterator()=default;
+  table_iterator():pc_{nullptr},p_{nullptr}{};
   template<bool Const2,typename std::enable_if<!Const2>::type* =nullptr>
   table_iterator(const table_iterator<TypePolicy,GroupPtr,Const2>& x):
     pc_{x.pc_},p_{x.p_}{}
@@ -133,10 +133,10 @@ private:
   template<typename> friend class table_erase_return_type;
   template<typename,typename,typename,typename> friend class table;
 
-  table_iterator(group_type* pg,std::size_t n,const table_element_type* p):
+  table_iterator(group_type* pg,std::size_t n,const table_element_type* ptet):
     pc_{to_pointer<char_pointer>(
       reinterpret_cast<unsigned char*>(const_cast<group_type*>(pg))+n)},
-    p_{to_pointer<table_element_pointer>(const_cast<table_element_type*>(p))}
+    p_{to_pointer<table_element_pointer>(const_cast<table_element_type*>(ptet))}
   {}
 
   unsigned char* pc()const noexcept{return boost::to_address(pc_);}
@@ -568,7 +568,7 @@ private:
 
   struct erase_on_exit
   {
-    erase_on_exit(table& x_,const_iterator it_):x{x_},it{it_}{}
+    erase_on_exit(table& x_,const_iterator it_):x(x_),it(it_){}
     ~erase_on_exit(){if(!rollback_)x.erase(it);}
 
     void rollback(){rollback_=true;}