diff --git a/compiler-rt/test/msan/strxfrm.cpp b/compiler-rt/test/msan/strxfrm.cpp
--- a/compiler-rt/test/msan/strxfrm.cpp
+++ b/compiler-rt/test/msan/strxfrm.cpp
@@ -7,7 +7,7 @@
 #include <string.h>
 
 int main(void) {
-  char q[10];
+  char q[30];
   size_t n = strxfrm(q, "abcdef", sizeof(q));
   assert(n < sizeof(q));
   __msan_check_mem_is_initialized(q, n + 1);