libstdc++: Fix up submdspan std exports

On Mon, Feb 16, 2026 at 01:34:50PM +0100, Tomasz Kamiński wrote:
> This patch implements LWG 4491, addressing C++26 NB comments.
>
> libstdc++-v3/ChangeLog:
>
>       * include/std/mdspan (std::submdspan_extents): Rename to...
>       (std::subextents): Rename of submdspan_extents.
>       (std::submdspan_canonicalize_slices): Rename to...
>       (std::canonical_slices):

This broke
+FAIL: g++.dg/modules/compile-std1.C -std=c++26 (test for excess errors)
+FAIL: g++.dg/modules/compile-std1.C module-cmi std (gcm.cache/std.gcm)
+FAIL: g++.dg/modules/compile-std1.C module-cmi std.compat (gcm.cache/std.compat.gcm)
on all targets.

The following patch fixes it.

2026-02-17  Jakub Jelinek  <jakub@redhat.com>

	* src/c++23/std.cc.in (std::submdspan_canonicalize_slices,
	std::submdspan_extents): Remove exports.
	(std::canonical_slices, std::subextents): New exports.

diff --git a/libstdc++-v3/src/c++23/std.cc.in b/libstdc++-v3/src/c++23/std.cc.in
index bcaa0cb51b607688bb4b58c596d257ffc6c3b090..514ac5939fef68661b836e677a395a6ad9823d05 100644 (file)
--- a/libstdc++-v3/src/c++23/std.cc.in
+++ b/libstdc++-v3/src/c++23/std.cc.in
@@ -1915,8 +1915,8 @@ export namespace std
   using std::full_extent_t;
   using std::full_extent;
   using std::submdspan_mapping_result;
-  using std::submdspan_canonicalize_slices;
-  using std::submdspan_extents;
+  using std::canonical_slices;
+  using std::subextents;
   using std::submdspan;
 #endif
 }