Remove usage of extern_weak in fast_thread_local

patches/0025-Remove-usage-of-extern_weak-in-fast_thread_local.patch

@@ -0,0 +1,45 @@
+From 7496bb94a2fb2bc34629c9781c3bc3a470becaee Mon Sep 17 00:00:00 2001
+From: bjorn3 <bjorn3@users.noreply.github.com>
+Date: Fri, 10 Apr 2020 13:47:42 +0200
+Subject: [PATCH] Remove usage of extern_weak in fast_thread_local 
+
+---
+ src/libstd/sys/unix/fast_thread_local.rs | 20 --------------------
+ 1 files changed, 0 insertions(+), 20 deletions(-)
+
+diff --git a/src/libstd/sys/unix/fast_thread_local.rs b/src/libstd/sys/unix/fast_thread_local.rs
+index 8730b4d..8d6e3d5 100644
+--- a/src/libstd/sys/unix/fast_thread_local.rs
++++ b/src/libstd/sys/unix/fast_thread_local.rs
+@@ -15,28 +15,8 @@
+     target_os = "emscripten"
+ ))]
+ pub unsafe fn register_dtor(t: *mut u8, dtor: unsafe extern "C" fn(*mut u8)) {
+-    use crate::mem;
+     use crate::sys_common::thread_local::register_dtor_fallback;
+ 
+-    extern "C" {
+-        #[linkage = "extern_weak"]
+-        static __dso_handle: *mut u8;
+-        #[linkage = "extern_weak"]
+-        static __cxa_thread_atexit_impl: *const libc::c_void;
+-    }
+-    if !__cxa_thread_atexit_impl.is_null() {
+-        type F = unsafe extern "C" fn(
+-            dtor: unsafe extern "C" fn(*mut u8),
+-            arg: *mut u8,
+-            dso_handle: *mut u8,
+-        ) -> libc::c_int;
+-        mem::transmute::<*const libc::c_void, F>(__cxa_thread_atexit_impl)(
+-            dtor,
+-            t,
+-            &__dso_handle as *const _ as *mut _,
+-        );
+-        return;
+-    }
+     register_dtor_fallback(t, dtor);
+ }
+ 
+-- 
+2.20.1
+