diff --git a/adb/client/incremental_server.cpp b/adb/client/incremental_server.cpp
index 9037672..726533d 100644
--- a/adb/client/incremental_server.cpp
+++ b/adb/client/incremental_server.cpp
@@ -146,7 +146,7 @@
     const unique_fd& RawFd() const { return fd_; }
 
     std::vector<bool> sentBlocks;
-    NumBlocks sentBlocksCount;
+    NumBlocks sentBlocksCount = 0;
 
     const char* const filepath;
     const FileId id;