diff --git a/libc/bionic/pthread_getcpuclockid.cpp b/libc/bionic/pthread_getcpuclockid.cpp
index dbfb7d4..2bf2004 100644
--- a/libc/bionic/pthread_getcpuclockid.cpp
+++ b/libc/bionic/pthread_getcpuclockid.cpp
@@ -31,11 +31,13 @@
 #include "pthread_internal.h"
 
 int pthread_getcpuclockid(pthread_t t, clockid_t* clockid) {
-  pid_t tid = reinterpret_cast<pthread_internal_t*>(t)->tid;
-  if (tid == 0) return ESRCH;
+  pthread_internal_t* thread = __pthread_internal_find(t);
+  if (thread == NULL) {
+    return ESRCH;
+  }
 
   // The tid is stored in the top bits, but negated.
-  clockid_t result = ~static_cast<clockid_t>(tid) << 3;
+  clockid_t result = ~static_cast<clockid_t>(thread->tid) << 3;
   // Bits 0 and 1: clock type (0 = CPUCLOCK_PROF, 1 = CPUCLOCK_VIRT, 2 = CPUCLOCK_SCHED).
   result |= 2;
   // Bit 2: thread (set) or process (clear)?