[WiP] Weak alias __cxa_thread_atexit_impl to musl's ___cxa_atexit

See: emscripten-core#15722.
kleisauke · Jan 12, 2023 · df11456 · df11456
1 parent 888f452
commit df11456
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Showing 3 changed files with 3 additions and 4 deletions.
diff --git a/system/lib/libc/musl/src/exit/atexit.c b/system/lib/libc/musl/src/exit/atexit.c
@@ -82,4 +82,5 @@ int __atexit(void (*func)(void))
 // in when EXIT_RUNTIME is set to 0.
 weak_alias(__atexit, atexit);
 weak_alias(___cxa_atexit, __cxa_atexit);
+weak_alias(___cxa_atexit, __cxa_thread_atexit_impl);
 weak_alias(___cxa_finalize, __cxa_finalize);
diff --git a/system/lib/libcxx/include/__config_site b/system/lib/libcxx/include/__config_site
@@ -5,3 +5,5 @@
 #define _LIBCPP_HAS_MUSL_LIBC
 #define _LIBCPP_ABI_NAMESPACE __2
 
+// Ensure we use the thread-local destructor implementation of musl.
+#define HAVE___CXA_THREAD_ATEXIT_IMPL
diff --git a/system/lib/libcxxabi/src/cxa_thread_atexit.cpp b/system/lib/libcxxabi/src/cxa_thread_atexit.cpp
@@ -112,13 +112,9 @@ extern "C" {
 #ifdef HAVE___CXA_THREAD_ATEXIT_IMPL
     return __cxa_thread_atexit_impl(dtor, obj, dso_symbol);
 #else
-#ifndef __EMSCRIPTEN__
-    // Emscripten doesn't fully support weak undefined symbols yet
-    // https://github.com/emscripten-core/emscripten/issues/12819
     if (__cxa_thread_atexit_impl) {
       return __cxa_thread_atexit_impl(dtor, obj, dso_symbol);
     } else
-#endif
     {
       // Initialize the dtors std::__libcpp_tls_key (uses __cxa_guard_*() for
       // one-time initialization and __cxa_atexit() for destruction)