[gcc r16-8579] libstdc++: Update __cpp_lib_function_ref value for P3948R1.

[Tomasz Kaminski]

https://gcc.gnu.org/g:2979e67af19d5c199a60b852efa8214131ba53ad

commit r16-8579-g2979e67af19d5c199a60b852efa8214131ba53ad
Author: Tomasz Kamiński <tkaminsk@redhat.com>
Date:   Wed Apr 8 17:35:46 2026 +0200

    libstdc++: Update __cpp_lib_function_ref value for P3948R1.
    
    SG-10 agreed on using 202604L value for paper P3961R0 that
    also updates __cpp_lib_function_ref macro.
    
    libstdc++-v3/ChangeLog:
    
            * include/bits/version.def (function_ref): Bump to 202603L.
            * include/bits/version.h: Regenerate.
            * testsuite/20_util/function_ref/assign.cc: Remove repeated
            check for feature test macro.
            * testsuite/20_util/function_ref/cons.cc: Updated checked
            value.
    
    Reviewed-by: Jonathan Wakely <jwakely@redhat.com>
    Signed-off-by: Tomasz Kamiński <tkaminsk@redhat.com>

Diff:
---
 libstdc++-v3/include/bits/version.def                 | 5 ++++-
 libstdc++-v3/include/bits/version.h                   | 4 ++--
 libstdc++-v3/testsuite/20_util/function_ref/assign.cc | 6 ------
 libstdc++-v3/testsuite/20_util/function_ref/cons.cc   | 2 +-
 4 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/libstdc++-v3/include/bits/version.def b/libstdc++-v3/include/bits/version.def
index 0142251ef936..3b4a0d4fdc05 100644
--- a/libstdc++-v3/include/bits/version.def
+++ b/libstdc++-v3/include/bits/version.def
@@ -1959,9 +1959,12 @@ ftms = {
 };
 
 ftms = {
+  // 202306 P0792R14 function_ref: a non-owning reference to a Callable
+  // 202511 P3774R1  Rename std::nontype, and make it broadly useful
+  // 202603 P3948R1  constant_wrapper is the only tool needed for passing...
   name = function_ref;
   values = {
-    v = 202306;
+    v = 202603;
     cxxmin = 26;
   };
 };
diff --git a/libstdc++-v3/include/bits/version.h b/libstdc++-v3/include/bits/version.h
index cf78137c9d1a..59719b4f8116 100644
--- a/libstdc++-v3/include/bits/version.h
+++ b/libstdc++-v3/include/bits/version.h
@@ -2183,9 +2183,9 @@
 
 #if !defined(__cpp_lib_function_ref)
 # if (__cplusplus >  202302L)
-#  define __glibcxx_function_ref 202306L
+#  define __glibcxx_function_ref 202603L
 #  if defined(__glibcxx_want_all) || defined(__glibcxx_want_function_ref)
-#   define __cpp_lib_function_ref 202306L
+#   define __cpp_lib_function_ref 202603L
 #  endif
 # endif
 #endif /* !defined(__cpp_lib_function_ref) */
diff --git a/libstdc++-v3/testsuite/20_util/function_ref/assign.cc b/libstdc++-v3/testsuite/20_util/function_ref/assign.cc
index 521a35fc11e0..eafea9aac241 100644
--- a/libstdc++-v3/testsuite/20_util/function_ref/assign.cc
+++ b/libstdc++-v3/testsuite/20_util/function_ref/assign.cc
@@ -2,12 +2,6 @@
 
 #include <functional>
 
-#ifndef __cpp_lib_function_ref
-# error "Feature-test macro for function_ref missing in <functional>"
-#elif __cpp_lib_function_ref != 202306L
-# error "Feature-test macro for function_ref has wrong value in <functional>"
-#endif
-
 using std::constant_wrapper;
 using std::function_ref;
 
diff --git a/libstdc++-v3/testsuite/20_util/function_ref/cons.cc b/libstdc++-v3/testsuite/20_util/function_ref/cons.cc
index 78aebd38a074..e6c13e3e538c 100644
--- a/libstdc++-v3/testsuite/20_util/function_ref/cons.cc
+++ b/libstdc++-v3/testsuite/20_util/function_ref/cons.cc
@@ -5,7 +5,7 @@
 
 #ifndef __cpp_lib_function_ref
 # error "Feature-test macro for function_ref missing in <functional>"
-#elif __cpp_lib_function_ref != 202306L
+#elif __cpp_lib_function_ref != 202603L
 # error "Feature-test macro for function_ref has wrong value in <functional>"
 #endif