After jemalloc was updated to version 5.0.0 in r319971, i386 executables

linked with AddressSanitizer (even those linked on earlier versions of
FreeBSD, or with external versions of clang) started failing with errors
similar to:

  ==14688==AddressSanitizer CHECK failed:
  /usr/src/contrib/compiler-rt/lib/asan/asan_poisoning.cc:36
  "((AddrIsAlignedByGranularity(addr))) != (0)" (0x0, 0x0)

This is because AddressSanitizer expects all the TLS data in the program
to be aligned to at least 8 bytes.

Before the jemalloc 5.0.0 update, all the TLS data in the i386 version
of libc.so added up to 80 bytes (a multiple of 8), but 5.0.0 made this
grow to 2404 bytes (not a multiple of 8).  This is due to added caching
data in jemalloc's internal struct tsd_s.

To fix AddressSanitizer, ensure this struct is aligned to at least 16
bytes, which can be done unconditionally for all architectures.  (An
earlier version of the fix aligned the struct to 8 bytes, but only for
ILP32 architectures.  This was deemed unnecessarily complicated.)

PR:		221337
X-MFC-With:	r319971

1 files changed, 2 insertions, 1 deletions

diff --git a/contrib/jemalloc/include/jemalloc/internal/tsd.h b/contrib/jemalloc/include/jemalloc/internal/tsd.h
index 155a2ec6c44b..fc14f8cea031 100644
--- a/contrib/jemalloc/include/jemalloc/internal/tsd.h
+++ b/contrib/jemalloc/include/jemalloc/internal/tsd.h
@@ -120,7 +120,8 @@ struct tsd_s {
 	t use_a_getter_or_setter_instead_##n;
 MALLOC_TSD
 #undef O
-};
+/* AddressSanitizer requires TLS data to be aligned to at least 8 bytes. */
+} JEMALLOC_ALIGNED(16);
 
 /*
  * Wrapper around tsd_t that makes it possible to avoid implicit conversion