diff --git a/src/google/protobuf/io/coded_stream.cc b/src/google/protobuf/io/coded_stream.cc
index 61f639308..6de9ea833 100644
--- a/src/google/protobuf/io/coded_stream.cc
+++ b/src/google/protobuf/io/coded_stream.cc
@@ -522,7 +522,7 @@ int CodedInputStream::ReadVarintSizeAsIntFallback() {
       // Optimization:  We're also safe if the buffer is non-empty and it ends
       // with a byte that would terminate a varint.
       (buffer_end_ > buffer_ && !(buffer_end_[-1] & 0x80))) {
-    uint64_t temp;
+    uint64_t temp = 0;
     ::std::pair<bool, const uint8_t*> p = ReadVarint64FromArray(buffer_, &temp);
     if (!p.first || temp > static_cast<uint64_t>(INT_MAX)) return -1;
     buffer_ = p.second;
@@ -632,7 +632,7 @@ std::pair<uint64_t, bool> CodedInputStream::ReadVarint64Fallback() {
       // Optimization:  We're also safe if the buffer is non-empty and it ends
       // with a byte that would terminate a varint.
       (buffer_end_ > buffer_ && !(buffer_end_[-1] & 0x80))) {
-    uint64_t temp;
+    uint64_t temp = 0;
     ::std::pair<bool, const uint8_t*> p = ReadVarint64FromArray(buffer_, &temp);
     if (!p.first) {
       return std::make_pair(0, false);