[Bug dynamic-link/27004] ld.so is miscompiled by GCC 11

[hjl.tools at gmail dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=27004

--- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> ---
How about this

diff --git a/sysdeps/x86_64/nptl/tls.h b/sysdeps/x86_64/nptl/tls.h
index a08bf972de..4eeab0e7a9 100644
--- a/sysdeps/x86_64/nptl/tls.h
+++ b/sysdeps/x86_64/nptl/tls.h
@@ -180,11 +180,19 @@ _Static_assert (offsetof (tcbhead_t, __glibc_unused2) ==
0x80,
    assignments like
        pthread_descr self = thread_self();
    do not get optimized away.  */
-# define THREAD_SELF \
+# if __GNUC_PREREQ (11, 0)
+#  define THREAD_SELF \
+  ({ struct pthread *__self;                                                 \
+     __self = (struct pthread *) (__builtin_thread_pointer ()                \
+                                 + offsetof (struct pthread, header.self));  \
+     __self;})
+# else
+#  define THREAD_SELF \
   ({ struct pthread *__self;                                                 \
      asm ("mov %%fs:%c1,%0" : "=r" (__self)                                  \
          : "i" (offsetof (struct pthread, header.self)));                    \
      __self;})
+# endif

 /* Magic for libthread_db to know how to do THREAD_SELF.  */
 # define DB_THREAD_SELF_INCLUDE  <sys/reg.h> /* For the FS constant.  */

-- 
You are receiving this mail because:
You are on the CC list for the bug.