commit ed86b7c065df6b33dfee86fba3bee089386ac4a8
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Thu Nov 7 23:20:51 2019 +0000

    libsupc++: add <compare> to precompiled header
    
    Also process it with Doxygen.
    
            * doc/doxygen/user.cfg.in (INPUT): Add <compare> header.
            * include/precompiled/stdc++.h: Include <compare> header.

diff --git a/libstdc++-v3/doc/doxygen/user.cfg.in b/libstdc++-v3/doc/doxygen/user.cfg.in
index 42001016721..18994703f0b 100644
--- a/libstdc++-v3/doc/doxygen/user.cfg.in
+++ b/libstdc++-v3/doc/doxygen/user.cfg.in
@@ -787,6 +787,7 @@ WARN_LOGFILE           =
 # Note: If this tag is empty the current directory is searched.
 
 INPUT                  = @srcdir@/doc/doxygen/doxygroups.cc \
+                         @srcdir@/libsupc++/compare \
                          @srcdir@/libsupc++/cxxabi.h \
                          @srcdir@/libsupc++/exception \
                          @srcdir@/libsupc++/initializer_list \
diff --git a/libstdc++-v3/include/precompiled/stdc++.h b/libstdc++-v3/include/precompiled/stdc++.h
index 57c3e2e32ee..118fc8f359a 100644
--- a/libstdc++-v3/include/precompiled/stdc++.h
+++ b/libstdc++-v3/include/precompiled/stdc++.h
@@ -135,7 +135,7 @@
 
 #if __cplusplus > 201703L
 #include <bit>
-// #include <compare>
+#include <compare>
 #include <concepts>
 #include <numbers>
 #include <ranges>