diff --git a/libc/bionic/malloc_heapprofd.h b/libc/bionic/malloc_heapprofd.h
index 5a766fc..9e846b6 100644
--- a/libc/bionic/malloc_heapprofd.h
+++ b/libc/bionic/malloc_heapprofd.h
@@ -40,4 +40,8 @@
 
 void HeapprofdInstallErrorSignalHandler();
 
+void HeapprofdMaskSignal();
+
+void HeapprofdUnmaskSignal();
+
 bool HeapprofdMallopt(int optcode, void* arg, size_t arg_size);