diff --git a/compiler-rt/test/sanitizer_common/TestCases/Linux/pthread_getaffinity_np.cpp b/compiler-rt/test/sanitizer_common/TestCases/Linux/pthread_getaffinity_np.cpp
--- a/compiler-rt/test/sanitizer_common/TestCases/Linux/pthread_getaffinity_np.cpp
+++ b/compiler-rt/test/sanitizer_common/TestCases/Linux/pthread_getaffinity_np.cpp
@@ -4,6 +4,7 @@
 
 #include <assert.h>
 #include <pthread.h>
+#include <stdio.h>
 #include <sys/sysinfo.h>
 
 #include <sanitizer/msan_interface.h>
@@ -11,6 +12,8 @@
 int main() {
   cpu_set_t set_x;
   int res = pthread_getaffinity_np(pthread_self(), sizeof(set_x), &set_x);
+  if (res != 0)
+    printf("res: %d\n", res);
   assert(res == 0);
   assert(CPU_COUNT_S(sizeof(set_x), &set_x) == get_nprocs());