[gcc r14-5301] libstdc++: declare std::allocator in !HOSTED as an extension

[gcc r14-5301] libstdc++: declare std::allocator in !HOSTED as an extension

[Arsen Arsenović]

https://gcc.gnu.org/g:d9dbc835d4d6353281218d030f5aed6fdef43a66

commit r14-5301-gd9dbc835d4d6353281218d030f5aed6fdef43a66
Author: Arsen Arsenović <arsen@aarsen.me>
Date:   Wed Nov 8 10:22:47 2023 +0100

    libstdc++: declare std::allocator in !HOSTED as an extension
    
    This allows us to add features to freestanding which allow specifying
    non-default allocators (generators, collections, ...) without having to
    modify them.
    
    libstdc++-v3/ChangeLog:
    
            * include/bits/memoryfwd.h: Remove HOSTED check around allocator
            and its specializations.

Diff:
---
 libstdc++-v3/include/bits/memoryfwd.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/libstdc++-v3/include/bits/memoryfwd.h b/libstdc++-v3/include/bits/memoryfwd.h
index 330a6df7f44..2b79cd8880a 100644
--- a/libstdc++-v3/include/bits/memoryfwd.h
+++ b/libstdc++-v3/include/bits/memoryfwd.h
@@ -60,13 +60,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    * @{
    */
 
-#if _GLIBCXX_HOSTED
+  // Included in freestanding as a libstdc++ extension.
   template<typename>
     class allocator;
 
   template<>
     class allocator<void>;
-#endif
 
 #if __cplusplus >= 201103L
   /// Declare uses_allocator so it can be specialized in `<queue>` etc.