From 9387ace326d73f4bc78b6334f32008b41439b169 Mon Sep 17 00:00:00 2001
From: Trung Nguyen <57174311+trungnt2910@users.noreply.github.com>
Date: Sun, 7 Jan 2024 13:17:34 +0000
Subject: [PATCH] third_party/libcxxabi: Enable __cxa_thread_atexit

Enable `__cxa_thread_atexit` from libcxxabi.
`__cxa_thread_atexit_impl` is still implemented by the cosmo libc.
The original `__cxa_thread_atexit` has been removed.
---
 libc/thread/__cxa_thread_atexit.c      | 23 -----------------------
 test/libc/thread/BUILD.mk              |  1 +
 third_party/libcxxabi/BUILD.mk         |  1 +
 third_party/libcxxabi/README.cosmo     |  1 +
 third_party/libcxxabi/include/cxxabi.h |  2 +-
 5 files changed, 4 insertions(+), 24 deletions(-)
 delete mode 100644 libc/thread/__cxa_thread_atexit.c

diff --git a/libc/thread/__cxa_thread_atexit.c b/libc/thread/__cxa_thread_atexit.c
deleted file mode 100644
index 2cb38f71e..000000000
--- a/libc/thread/__cxa_thread_atexit.c
+++ /dev/null
@@ -1,23 +0,0 @@
-/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
-│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8                               :vi │
-╞══════════════════════════════════════════════════════════════════════════════╡
-│ Copyright 2023 Justine Alexandra Roberts Tunney                              │
-│                                                                              │
-│ Permission to use, copy, modify, and/or distribute this software for         │
-│ any purpose with or without fee is hereby granted, provided that the         │
-│ above copyright notice and this permission notice appear in all copies.      │
-│                                                                              │
-│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
-│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
-│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
-│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
-│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
-│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
-│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
-│ PERFORMANCE OF THIS SOFTWARE.                                                │
-╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/intrin/cxaatexit.internal.h"
-
-int __cxa_thread_atexit(void *fun, void *arg, void *dso_symbol) {
-  return __cxa_thread_atexit_impl(fun, arg, dso_symbol);
-}
diff --git a/test/libc/thread/BUILD.mk b/test/libc/thread/BUILD.mk
index d40095c18..5cadbff27 100644
--- a/test/libc/thread/BUILD.mk
+++ b/test/libc/thread/BUILD.mk
@@ -41,6 +41,7 @@ TEST_LIBC_THREAD_DIRECTDEPS =				\
 	LIBC_THREAD					\
 	LIBC_TIME					\
 	LIBC_X						\
+	THIRD_PARTY_LIBCXXABI				\
 	THIRD_PARTY_NSYNC				\
 	THIRD_PARTY_NSYNC_MEM
 
diff --git a/third_party/libcxxabi/BUILD.mk b/third_party/libcxxabi/BUILD.mk
index 8eec30c7c..256ce3c45 100644
--- a/third_party/libcxxabi/BUILD.mk
+++ b/third_party/libcxxabi/BUILD.mk
@@ -90,6 +90,7 @@ $(THIRD_PARTY_LIBCXXABI_A_OBJS): private				\
 			-frtti						\
 			-D_LIBCXXABI_BUILDING_LIBRARY			\
 			-D_LIBCPP_BUILDING_LIBRARY			\
+			-DHAVE___CXA_THREAD_ATEXIT_IMPL			\
 			-D_LIBCPP_CONSTINIT=__constinit			\
 			-Dconstinit=__constinit
 
diff --git a/third_party/libcxxabi/README.cosmo b/third_party/libcxxabi/README.cosmo
index 6167e2b8b..41e62149b 100644
--- a/third_party/libcxxabi/README.cosmo
+++ b/third_party/libcxxabi/README.cosmo
@@ -15,3 +15,4 @@ LOCAL CHANGES
 
   - Add <__memory/aligned_alloc.h> (contains a few inline functions) from
   upstream libcxx.
+  - Enable __cxa_thread_atexit for Cosmopolitan.
diff --git a/third_party/libcxxabi/include/cxxabi.h b/third_party/libcxxabi/include/cxxabi.h
index 51d534eed..d1d6912e3 100644
--- a/third_party/libcxxabi/include/cxxabi.h
+++ b/third_party/libcxxabi/include/cxxabi.h
@@ -160,7 +160,7 @@ __cxa_decrement_exception_refcount(void *primary_exception) throw();
 extern _LIBCXXABI_FUNC_VIS bool __cxa_uncaught_exception() throw();
 extern _LIBCXXABI_FUNC_VIS unsigned int __cxa_uncaught_exceptions() throw();
 
-#if defined(__linux__) || defined(__Fuchsia__)
+#if defined(__linux__) || defined(__Fuchsia__) || defined(__COSMOPOLITAN__)
 // Linux and Fuchsia TLS support. Not yet an official part of the Itanium ABI.
 // https://sourceware.org/glibc/wiki/Destructor%20support%20for%20thread_local%20variables
 extern _LIBCXXABI_FUNC_VIS int __cxa_thread_atexit(void (*)(void *), void *,