Merge pull request #16398 from markdroth/round_robin_size_t_fix

Fix round_robin to avoid negative size_t value.

1 files changed, 3 insertions, 2 deletions

diff --git a/src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc b/src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc
index c730b3bd2b..4195c1e9d1 100644
--- a/src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc
+++ b/src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc
@@ -139,7 +139,8 @@ class RoundRobin : public LoadBalancingPolicy {
         grpc_client_channel_factory* client_channel_factory,
         const grpc_channel_args& args)
         : SubchannelList(policy, tracer, addresses, combiner,
-                         client_channel_factory, args) {
+                         client_channel_factory, args),
+          last_ready_index_(num_subchannels() - 1) {
       // Need to maintain a ref to the LB policy as long as we maintain
       // any references to subchannels, since the subchannels'
       // pollset_sets will include the LB policy's pollset_set.
@@ -180,7 +181,7 @@ class RoundRobin : public LoadBalancingPolicy {
     size_t num_connecting_ = 0;
     size_t num_transient_failure_ = 0;
     grpc_error* last_transient_failure_error_ = GRPC_ERROR_NONE;
-    size_t last_ready_index_ = -1;  // Index into list of last pick.
+    size_t last_ready_index_;  // Index into list of last pick.
   };
 
   // Helper class to ensure that any function that modifies the child refs