diff --git a/libsanitizer/Makefile.in b/libsanitizer/Makefile.in
index 65e7f2e9553..f11219cae84 100644
--- a/libsanitizer/Makefile.in
+++ b/libsanitizer/Makefile.in
@@ -214,6 +214,7 @@ ALLOC_FILE = @ALLOC_FILE@
 AMTAR = @AMTAR@
 AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
 AR = @AR@
+AS_SYM_ASSIGN_DEFS = @AS_SYM_ASSIGN_DEFS@
 AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@
diff --git a/libsanitizer/asan/Makefile.am b/libsanitizer/asan/Makefile.am
index 223d3e07816..6af250e99d9 100644
--- a/libsanitizer/asan/Makefile.am
+++ b/libsanitizer/asan/Makefile.am
@@ -3,7 +3,7 @@ AM_CPPFLAGS = -I $(top_srcdir)/include -I $(top_srcdir)
 # May be used by toolexeclibdir.
 gcc_version := $(shell @get_gcc_base_ver@ $(top_srcdir)/../gcc/BASE-VER)
 
-DEFS = -D_GNU_SOURCE -D_DEBUG -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -DASAN_HAS_EXCEPTIONS=1 -DASAN_NEEDS_SEGV=1 -DCAN_SANITIZE_UB=0 -DASAN_HAS_CXA_RETHROW_PRIMARY_EXCEPTION=0
+DEFS = -D_GNU_SOURCE -D_DEBUG -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -DASAN_HAS_EXCEPTIONS=1 -DASAN_NEEDS_SEGV=1 -DCAN_SANITIZE_UB=0 -DASAN_HAS_CXA_RETHROW_PRIMARY_EXCEPTION=0 @AS_SYM_ASSIGN_DEFS@
 if USING_MAC_INTERPOSE
 DEFS += -DMAC_INTERPOSE_FUNCTIONS -DMISSING_BLOCKS_SUPPORT
 endif
diff --git a/libsanitizer/asan/Makefile.in b/libsanitizer/asan/Makefile.in
index e88e5e0b0a7..ac72e13830f 100644
--- a/libsanitizer/asan/Makefile.in
+++ b/libsanitizer/asan/Makefile.in
@@ -264,6 +264,7 @@ ALLOC_FILE = @ALLOC_FILE@
 AMTAR = @AMTAR@
 AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
 AR = @AR@
+AS_SYM_ASSIGN_DEFS = @AS_SYM_ASSIGN_DEFS@
 AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@
@@ -288,7 +289,7 @@ DEFS = -D_GNU_SOURCE -D_DEBUG -D__STDC_CONSTANT_MACROS \
 	-D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS \
 	-DASAN_HAS_EXCEPTIONS=1 -DASAN_NEEDS_SEGV=1 \
 	-DCAN_SANITIZE_UB=0 -DASAN_HAS_CXA_RETHROW_PRIMARY_EXCEPTION=0 \
-	$(am__append_1)
+	@AS_SYM_ASSIGN_DEFS@ $(am__append_1)
 DEPDIR = @DEPDIR@
 DSYMUTIL = @DSYMUTIL@
 DUMPBIN = @DUMPBIN@
diff --git a/libsanitizer/configure b/libsanitizer/configure
index 2edd5c37ce7..6bfd28916d2 100755
--- a/libsanitizer/configure
+++ b/libsanitizer/configure
@@ -651,6 +651,7 @@ ALLOC_FILE
 VIEW_FILE
 BACKTRACE_SUPPORTED
 FORMAT_FILE
+AS_SYM_ASSIGN_DEFS
 SANITIZER_SUPPORTED_FALSE
 SANITIZER_SUPPORTED_TRUE
 USING_MAC_INTERPOSE_FALSE
@@ -12474,7 +12475,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12477 "configure"
+#line 12478 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12580,7 +12581,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12583 "configure"
+#line 12584 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -16333,6 +16334,38 @@ $as_echo "#define HAVE_ATOMIC_FUNCTIONS 1" >>confdefs.h
 
 fi
 
+# Check if assembler supports symbol assignment.
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler symbol assignment" >&5
+$as_echo_n "checking assembler symbol assignment... " >&6; }
+if ${libsanitizer_cv_as_sym_assign+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+asm("a = b");
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  libsanitizer_cv_as_sym_assign=yes
+else
+  libsanitizer_cv_as_sym_assign=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libsanitizer_cv_as_sym_assign" >&5
+$as_echo "$libsanitizer_cv_as_sym_assign" >&6; }
+if test "$libsanitizer_cv_as_sym_assign" = "yes"; then
+  as_sym_assign_defs=-DHAVE_AS_SYM_ASSIGN=1
+fi
+AS_SYM_ASSIGN_DEFS=$as_sym_assign_defs
+
+
 # The library needs to be able to read the executable itself.  Compile
 # a file to determine the executable format.  The awk script
 # filetype.awk prints out the file type.
diff --git a/libsanitizer/configure.ac b/libsanitizer/configure.ac
index 5906c8d4887..8037c941774 100644
--- a/libsanitizer/configure.ac
+++ b/libsanitizer/configure.ac
@@ -214,6 +214,19 @@ if test "$libsanitizer_cv_sys_atomic" = "yes"; then
 	    [Define to 1 if you have the __atomic functions])
 fi
 
+# Check if assembler supports symbol assignment.
+AC_CACHE_CHECK([assembler symbol assignment],
+[libsanitizer_cv_as_sym_assign],
+[AC_COMPILE_IFELSE(
+  [AC_LANG_PROGRAM([],
+		   [asm("a = b");])],
+  [libsanitizer_cv_as_sym_assign=yes],
+  [libsanitizer_cv_as_sym_assign=no])])
+if test "$libsanitizer_cv_as_sym_assign" = "yes"; then
+  as_sym_assign_defs=-DHAVE_AS_SYM_ASSIGN=1
+fi
+AC_SUBST(AS_SYM_ASSIGN_DEFS, [$as_sym_assign_defs])
+
 # The library needs to be able to read the executable itself.  Compile
 # a file to determine the executable format.  The awk script
 # filetype.awk prints out the file type.
diff --git a/libsanitizer/hwasan/Makefile.in b/libsanitizer/hwasan/Makefile.in
index 87971fd3374..4420bd6a7a9 100644
--- a/libsanitizer/hwasan/Makefile.in
+++ b/libsanitizer/hwasan/Makefile.in
@@ -260,6 +260,7 @@ ALLOC_FILE = @ALLOC_FILE@
 AMTAR = @AMTAR@
 AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
 AR = @AR@
+AS_SYM_ASSIGN_DEFS = @AS_SYM_ASSIGN_DEFS@
 AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@
diff --git a/libsanitizer/interception/Makefile.in b/libsanitizer/interception/Makefile.in
index 85dd386de47..2d807c98d3b 100644
--- a/libsanitizer/interception/Makefile.in
+++ b/libsanitizer/interception/Makefile.in
@@ -186,6 +186,7 @@ ALLOC_FILE = @ALLOC_FILE@
 AMTAR = @AMTAR@
 AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
 AR = @AR@
+AS_SYM_ASSIGN_DEFS = @AS_SYM_ASSIGN_DEFS@
 AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@
diff --git a/libsanitizer/libbacktrace/Makefile.in b/libsanitizer/libbacktrace/Makefile.in
index c0243fa4aab..33faa78bb43 100644
--- a/libsanitizer/libbacktrace/Makefile.in
+++ b/libsanitizer/libbacktrace/Makefile.in
@@ -236,6 +236,7 @@ ALLOC_FILE = @ALLOC_FILE@
 AMTAR = @AMTAR@
 AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
 AR = @AR@
+AS_SYM_ASSIGN_DEFS = @AS_SYM_ASSIGN_DEFS@
 AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@
diff --git a/libsanitizer/lsan/Makefile.in b/libsanitizer/lsan/Makefile.in
index 078edf01fda..0870f9e7136 100644
--- a/libsanitizer/lsan/Makefile.in
+++ b/libsanitizer/lsan/Makefile.in
@@ -231,6 +231,7 @@ ALLOC_FILE = @ALLOC_FILE@
 AMTAR = @AMTAR@
 AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
 AR = @AR@
+AS_SYM_ASSIGN_DEFS = @AS_SYM_ASSIGN_DEFS@
 AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@
diff --git a/libsanitizer/sanitizer_common/Makefile.in b/libsanitizer/sanitizer_common/Makefile.in
index 881df60331b..45141930f9f 100644
--- a/libsanitizer/sanitizer_common/Makefile.in
+++ b/libsanitizer/sanitizer_common/Makefile.in
@@ -224,6 +224,7 @@ ALLOC_FILE = @ALLOC_FILE@
 AMTAR = @AMTAR@
 AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
 AR = @AR@
+AS_SYM_ASSIGN_DEFS = @AS_SYM_ASSIGN_DEFS@
 AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@
diff --git a/libsanitizer/tsan/Makefile.in b/libsanitizer/tsan/Makefile.in
index fc14a42c082..5cc6f95a40a 100644
--- a/libsanitizer/tsan/Makefile.in
+++ b/libsanitizer/tsan/Makefile.in
@@ -260,6 +260,7 @@ ALLOC_FILE = @ALLOC_FILE@
 AMTAR = @AMTAR@
 AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
 AR = @AR@
+AS_SYM_ASSIGN_DEFS = @AS_SYM_ASSIGN_DEFS@
 AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@
diff --git a/libsanitizer/ubsan/Makefile.in b/libsanitizer/ubsan/Makefile.in
index 7e51480e970..717d1571556 100644
--- a/libsanitizer/ubsan/Makefile.in
+++ b/libsanitizer/ubsan/Makefile.in
@@ -225,6 +225,7 @@ ALLOC_FILE = @ALLOC_FILE@
 AMTAR = @AMTAR@
 AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
 AR = @AR@
+AS_SYM_ASSIGN_DEFS = @AS_SYM_ASSIGN_DEFS@
 AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@