[PATCH] libsanitizer: cherry-pick commit 05551c658269 from upstream

[H.J. Lu via Gcc-patches]

cherry-pick:

05551c658269 [sanitizer] Correct alignment of x32 __sanitizer_siginfo

        * sanitizer_common/sanitizer_platform_limits_posix.h
        (__sanitizer_siginfo_pad): Use u64 to align x32
        __sanitizer_siginfo to 8 bytes.
---
 .../sanitizer_common/sanitizer_platform_limits_posix.h       | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h 
b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h
index cfca7bdedbe..e6f298c26e1 100644
--- a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h
+++ b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h
@@ -578,8 +578,13 @@ struct __sanitizer_sigset_t {
 #endif
 
 struct __sanitizer_siginfo_pad {
+#if SANITIZER_X32
+  // x32 siginfo_t is aligned to 8 bytes.
+  u64 pad[128 / sizeof(u64)];
+#else
   // Require uptr, because siginfo_t is always pointer-size aligned on Linux.
   uptr pad[128 / sizeof(uptr)];
+#endif
 };
 
 #if SANITIZER_LINUX
-- 
2.40.0