diff --git a/libc/Android.mk b/libc/Android.mk
index 340228b..b9db201 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -247,6 +247,7 @@
     bionic/seteuid.cpp \
     bionic/setlocale.cpp \
     bionic/signalfd.cpp \
+    bionic/sigprocmask.cpp \
     bionic/sigwait.cpp \
     bionic/statvfs.cpp \
     bionic/strerror.cpp \