diff --git a/libc/bionic/sigemptyset.cpp b/libc/bionic/sigemptyset.cpp
index 8d8033f99..58166a1a9 100644
--- a/libc/bionic/sigemptyset.cpp
+++ b/libc/bionic/sigemptyset.cpp
@@ -28,6 +28,7 @@
 
 #include <errno.h>
 #include <signal.h>
+#include <string.h>
 
 int sigemptyset(sigset_t* set) {
   if (set == NULL) {
diff --git a/libc/bionic/sigfillset.cpp b/libc/bionic/sigfillset.cpp
index 37792e55b..cb673942e 100644
--- a/libc/bionic/sigfillset.cpp
+++ b/libc/bionic/sigfillset.cpp
@@ -28,6 +28,7 @@
 
 #include <errno.h>
 #include <signal.h>
+#include <string.h>
 
 int sigfillset(sigset_t* set) {
   if (set == NULL) {
diff --git a/libc/include/signal.h b/libc/include/signal.h
index 898888809..39d37e9cb 100644
--- a/libc/include/signal.h
+++ b/libc/include/signal.h
@@ -33,7 +33,6 @@
 #include <limits.h>
 #include <machine/pthread_types.h>
 #include <machine/timespec.h>
-#include <string.h>
 #include <sys/cdefs.h>
 #include <sys/types.h>