From b581fd421af5691bdafda7d30b20723f77d0cc88 Mon Sep 17 00:00:00 2001
From: Andreas Kling <awesomekling@gmail.com>
Date: Mon, 16 May 2022 15:08:53 +0200
Subject: [PATCH 6/6] libstdc++: Support SerenityOS

During the toolchain build, SerenityOS libraries are not available, so
we have to manually tell libstdc++ about what our LibC supports.

In most places, we take the Newlib code paths.

Co-Authored-By: Gunnar Beutner <gbeutner@serenityos.org>
Co-Authored-By: Daniel Bertalan <dani@danielbertalan.dev>
Co-Authored-By: Itamar <itamar8910@gmail.com>
Co-Authored-By: James Mintram <me@jamesrm.com>
Co-Authored-By: Martin Bříza <m@rtinbriza.cz>
Co-Authored-By: Nico Weber <thakis@chromium.org>
Co-Authored-By: Philip Herron <herron.philip@googlemail.com>
Co-Authored-By: Shannon Booth <shannon.ml.booth@gmail.com>
---
 libstdc++-v3/acinclude.m4   |  4 ++--
 libstdc++-v3/configure      | 11 ++++++++---
 libstdc++-v3/configure.host |  3 +++
 libstdc++-v3/crossconfig.m4 |  2 +-
 4 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4
index 138bd58d8..6cd7564b6 100644
--- a/libstdc++-v3/acinclude.m4
+++ b/libstdc++-v3/acinclude.m4
@@ -1374,7 +1374,7 @@ AC_DEFUN([GLIBCXX_ENABLE_LIBSTDCXX_TIME], [
         ac_has_nanosleep=yes
         ac_has_sched_yield=yes
         ;;
-      freebsd*|netbsd*|dragonfly*|rtems*)
+      freebsd*|netbsd*|dragonfly*|rtems*|serenity*)
         ac_has_clock_monotonic=yes
         ac_has_clock_realtime=yes
         ac_has_nanosleep=yes
@@ -2421,7 +2421,7 @@ AC_DEFUN([GLIBCXX_ENABLE_CLOCALE], [
       dragonfly* | freebsd*)
 	enable_clocale_flag=dragonfly
 	;;
-      openbsd*)
+      openbsd* | serenity*)
 	enable_clocale_flag=newlib
 	;;
       *)
diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
index 9b94fd71e..51e45878f 100755
--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@@ -11914,6 +11914,11 @@ else
     lt_cv_dlopen_libs=
     ;;
 
+  serenity*)
+    lt_cv_dlopen="dlopen"
+    lt_cv_dlopen_libs="-ldl"
+    ;;
+
   darwin*)
   # if libdl is installed we need to link against it
     { $as_echo "$as_me:${as_lineno-$LINENO}: checking for dlopen in -ldl" >&5
@@ -16478,7 +16483,7 @@ fi
       dragonfly* | freebsd*)
 	enable_clocale_flag=dragonfly
 	;;
-      openbsd*)
+      openbsd* | serenity*)
 	enable_clocale_flag=newlib
 	;;
       *)
@@ -20569,7 +20574,7 @@ fi
         ac_has_nanosleep=yes
         ac_has_sched_yield=yes
         ;;
-      freebsd*|netbsd*|dragonfly*|rtems*)
+      freebsd*|netbsd*|dragonfly*|rtems*|serenity*)
         ac_has_clock_monotonic=yes
         ac_has_clock_realtime=yes
         ac_has_nanosleep=yes
@@ -29245,7 +29250,7 @@ case "${host}" in
     # This is a freestanding configuration; there is nothing to do here.
     ;;
 
-  avr*-*-*)
+  avr*-*-* | *serenity*)
     $as_echo "#define HAVE_ACOSF 1" >>confdefs.h
 
     $as_echo "#define HAVE_ASINF 1" >>confdefs.h
diff --git a/libstdc++-v3/configure.host b/libstdc++-v3/configure.host
index ec32980aa..e060300f3 100644
--- a/libstdc++-v3/configure.host
+++ b/libstdc++-v3/configure.host
@@ -297,6 +297,9 @@ case "${host_os}" in
     # Use libatomic if necessary and avoid libstdc++ specific atomicity support
     atomicity_dir="cpu/generic/atomicity_builtins"
     ;;
+  serenity*)
+    os_include_dir="os/newlib"
+    ;;
   solaris2*)
     os_include_dir="os/solaris"
     ;;
diff --git a/libstdc++-v3/crossconfig.m4 b/libstdc++-v3/crossconfig.m4
index ae5283b7a..b9fc96e94 100644
--- a/libstdc++-v3/crossconfig.m4
+++ b/libstdc++-v3/crossconfig.m4
@@ -9,7 +9,7 @@ case "${host}" in
     # This is a freestanding configuration; there is nothing to do here.
     ;;
 
-  avr*-*-*)
+  avr*-*-* | *serenity*)
     AC_DEFINE(HAVE_ACOSF)
     AC_DEFINE(HAVE_ASINF)
     AC_DEFINE(HAVE_ATAN2F)
-- 
2.36.1