diff --git a/src/core/surface/call.c b/src/core/surface/call.c
index aa435d44d38..86d5fca3880 100644
--- a/src/core/surface/call.c
+++ b/src/core/surface/call.c
@@ -922,7 +922,8 @@ static batch_control *allocate_batch_control(grpc_call *call) {
   size_t i;
   for (i = 0; i < MAX_CONCURRENT_BATCHES; i++) {
     if ((call->used_batches & (1 << i)) == 0) {
-      call->used_batches |= (gpr_uint8)(1 << i);
+      call->used_batches =
+          (gpr_uint8)(call->used_batches | (gpr_uint8)(1 << i));
       return &call->active_batches[i];
     }
   }
diff --git a/test/core/transport/chttp2/hpack_table_test.c b/test/core/transport/chttp2/hpack_table_test.c
index db55c277832..5bdeeafb677 100644
--- a/test/core/transport/chttp2/hpack_table_test.c
+++ b/test/core/transport/chttp2/hpack_table_test.c
@@ -174,7 +174,7 @@ static grpc_chttp2_hptbl_find_result find_simple(grpc_chttp2_hptbl *tbl,
 
 static void test_find(void) {
   grpc_chttp2_hptbl tbl;
-  int i;
+  gpr_uint32 i;
   char buffer[32];
   grpc_mdctx *mdctx;
   grpc_chttp2_hptbl_find_result r;
@@ -254,7 +254,7 @@ static void test_find(void) {
   GPR_ASSERT(r.has_value == 1);
 
   for (i = 0; i < tbl.num_ents; i++) {
-    int expect = 9999 - i;
+    gpr_uint32 expect = 9999 - i;
     gpr_ltoa(expect, buffer);
 
     r = find_simple(&tbl, "test", buffer);