PR65122 extended alignment support in allocators

	PR libstdc++/65122
	* include/ext/malloc_allocator.h (malloc_allocator::allocate): Use
	aligned_alloc for types with extended alignment if available,
	otherwise throw bad_alloc if malloc doesn't return a suitable value.
	* include/ext/bitmap_allocator.h (bitmap_allocator::allocate)
	(bitmap_allocator::deallocate): Use aligned new/delete for types with
	extended alignment.
	* include/ext/mt_allocator.h (__mt_alloc::allocate)
	(__mt_alloc::deallocate): Likewise.
	* include/ext/new_allocator.h (new_allocator::allocate)
	(new_allocator::deallocate): Likewise.
	* include/ext/pool_allocator.h (__pool_alloc::allocate)
	(__pool_alloc::deallocate): Likewise.
	* testsuite/20_util/allocator/overaligned.cc: New test.
	* testsuite/ext/bitmap_allocator/overaligned.cc: New test.
	* testsuite/ext/malloc_allocator/overaligned.cc: New test.
	* testsuite/ext/mt_allocator/overaligned.cc: New test.
	* testsuite/ext/new_allocator/overaligned.cc: New test.
	* testsuite/ext/pool_allocator/overaligned.cc: New test.

From-SVN: r241158

1 files changed, 18 insertions, 0 deletions

diff --git a/libstdc++-v3/include/ext/mt_allocator.h b/libstdc++-v3/include/ext/mt_allocator.h
index 7016e48..d7ea7c1 100644
--- a/libstdc++-v3/include/ext/mt_allocator.h
+++ b/libstdc++-v3/include/ext/mt_allocator.h
@@ -691,6 +691,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       if (__n > this->max_size())
 	std::__throw_bad_alloc();
 
+#if __cpp_aligned_new
+      // Types with extended alignment are handled by operator new/delete.
+      if (alignof(_Tp) > __STDCPP_DEFAULT_NEW_ALIGNMENT__)
+	{
+	  std::align_val_t __al = std::align_val_t(alignof(_Tp));
+	  return static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), __al));
+	}
+#endif
+
       __policy_type::_S_initialize_once();
 
       // Requests larger than _M_max_bytes are handled by operator
@@ -737,6 +746,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     {
       if (__builtin_expect(__p != 0, true))
 	{
+#if __cpp_aligned_new
+	  // Types with extended alignment are handled by operator new/delete.
+	  if (alignof(_Tp) > __STDCPP_DEFAULT_NEW_ALIGNMENT__)
+	    {
+	      ::operator delete(__p, std::align_val_t(alignof(_Tp)));
+	      return;
+	    }
+#endif
+
 	  // Requests larger than _M_max_bytes are handled by
 	  // operators new/delete directly.
 	  __pool_type& __pool = __policy_type::_S_get_pool();