From 74ca1e50f3eabc0997c0b7504d828a7cd92822d7 Mon Sep 17 00:00:00 2001
From: joaquintides <joaquin@tid.es>
Date: Fri, 7 Oct 2022 11:27:54 +0200
Subject: [PATCH] return one lambda expression back in place (related to
 f1eb5d2106d666bb7fd620430e4ce48c257605e2)

---
 include/boost/unordered/detail/foa.hpp | 41 +++++++++++++-------------
 1 file changed, 20 insertions(+), 21 deletions(-)

diff --git a/include/boost/unordered/detail/foa.hpp b/include/boost/unordered/detail/foa.hpp
index 33c53c27..39da1f26 100644
--- a/include/boost/unordered/detail/foa.hpp
+++ b/include/boost/unordered/detail/foa.hpp
@@ -979,35 +979,19 @@ public:
     static constexpr auto pocma=
       alloc_traits::propagate_on_container_move_assignment::value;
 
-    /*  Avoid using nested lambdas with a `this` capture as it seems to trigger
+    /* Avoid using nested lambdas with a `this` capture as it seems to trigger
      * a bug in GCC:
      * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80947
      * 
      * Rather than directly attempting to manipulate the visibility of the
      * table class, it's easier to work around the bug by simply un-nesting the
-     * lambdas
+     * lambda.
      */
+
     auto const move_element=[this](value_type* p){
       unchecked_insert(std::move(*p));
     };
 
-    auto const elementwise_move=[&,this]{
-      reserve(x.size());
-      BOOST_TRY{
-        /* This works because subsequent x.clear() does not depend on the
-         * elements' values.
-         */
-
-        x.for_all_elements(move_element);
-      }
-      BOOST_CATCH(...){
-        x.clear();
-        BOOST_RETHROW
-      }
-      BOOST_CATCH_END
-      x.clear();
-    };
-
     if(this!=&x){
       clear();
       h()=std::move(x.h());
@@ -1020,12 +1004,27 @@ public:
         swap(arrays,x.arrays);
         swap(ml,x.ml);
       }
-      else if_constexpr<!alloc_traits::is_always_equal::value>(
+      else if_constexpr<!alloc_traits::is_always_equal::value>([&,this]{
         /* The check above is redundant: we're setting up a compile-time
          * barrier so that the compiler is convinced we're not throwing
          * under noexcept(true) conditions.
          */
-        elementwise_move);
+
+        reserve(x.size());
+        BOOST_TRY{
+          /* This works because subsequent x.clear() does not depend on the
+           * elements' values.
+           */
+
+          x.for_all_elements(move_element);
+        }
+        BOOST_CATCH(...){
+          x.clear();
+          BOOST_RETHROW
+        }
+        BOOST_CATCH_END
+        x.clear();
+      });
     }
     return *this;
   }