diff --git a/libc/bionic/pthread_setname_np.cpp b/libc/bionic/pthread_setname_np.cpp
index 93d4b2f..c4e9fb8 100644
--- a/libc/bionic/pthread_setname_np.cpp
+++ b/libc/bionic/pthread_setname_np.cpp
@@ -30,6 +30,7 @@
 
 #include <fcntl.h>
 #include <stdio.h> // For snprintf.
+#include <string.h>
 #include <sys/prctl.h>
 #include <sys/stat.h>
 #include <sys/types.h>