Fix tests.

57 files changed, 191 insertions, 180 deletions

diff --git a/test/core/bad_ssl/bad_ssl_test.c b/test/core/bad_ssl/bad_ssl_test.c
index f8a9fe6cac..41b514be1c 100644
--- a/test/core/bad_ssl/bad_ssl_test.c
+++ b/test/core/bad_ssl/bad_ssl_test.c
@@ -100,7 +100,7 @@ static void run_test(const char *target, size_t nops) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/client_channel/lb_policies_test.c b/test/core/client_channel/lb_policies_test.c
index f46982a387..a34741ee47 100644
--- a/test/core/client_channel/lb_policies_test.c
+++ b/test/core/client_channel/lb_policies_test.c
@@ -312,7 +312,8 @@ static request_sequences perform_request(servers_fixture *f,
     op->reserved = NULL;
     op++;
     op->op = GRPC_OP_RECV_INITIAL_METADATA;
-    op->data.recv_initial_metadata = &rdata->initial_metadata_recv;
+    op->data.recv_initial_metadata.recv_initial_metadata =
+        &rdata->initial_metadata_recv;
     op->flags = 0;
     op->reserved = NULL;
     op++;
diff --git a/test/core/end2end/bad_server_response_test.c b/test/core/end2end/bad_server_response_test.c
index a052016883..d3a47ab34d 100644
--- a/test/core/end2end/bad_server_response_test.c
+++ b/test/core/end2end/bad_server_response_test.c
@@ -198,7 +198,7 @@ static void start_rpc(int target_port, grpc_status_code expected_status,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/dualstack_socket_test.c b/test/core/end2end/dualstack_socket_test.c
index 11e8604f56..59079f5445 100644
--- a/test/core/end2end/dualstack_socket_test.c
+++ b/test/core/end2end/dualstack_socket_test.c
@@ -184,7 +184,7 @@ void test_connect(const char *server_host, const char *client_host, int port,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/fixtures/proxy.c b/test/core/end2end/fixtures/proxy.c
index beed80df81..70d8da48ae 100644
--- a/test/core/end2end/fixtures/proxy.c
+++ b/test/core/end2end/fixtures/proxy.c
@@ -203,7 +203,7 @@ static void on_p2s_sent_message(void *arg, int success) {
     op.op = GRPC_OP_RECV_MESSAGE;
     op.flags = 0;
     op.reserved = NULL;
-    op.data.recv_message = &pc->c2p_msg;
+    op.data.recv_message.recv_message = &pc->c2p_msg;
     refpc(pc, "on_c2p_recv_msg");
     err = grpc_call_start_batch(pc->c2p, &op, 1,
                                 new_closure(on_c2p_recv_msg, pc), NULL);
@@ -228,7 +228,7 @@ static void on_c2p_recv_msg(void *arg, int success) {
       op.op = GRPC_OP_SEND_MESSAGE;
       op.flags = 0;
       op.reserved = NULL;
-      op.data.send_message = pc->c2p_msg;
+      op.data.send_message.send_message = pc->c2p_msg;
       refpc(pc, "on_p2s_sent_message");
       err = grpc_call_start_batch(pc->p2s, &op, 1,
                                   new_closure(on_p2s_sent_message, pc), NULL);
@@ -259,7 +259,7 @@ static void on_c2p_sent_message(void *arg, int success) {
     op.op = GRPC_OP_RECV_MESSAGE;
     op.flags = 0;
     op.reserved = NULL;
-    op.data.recv_message = &pc->p2s_msg;
+    op.data.recv_message.recv_message = &pc->p2s_msg;
     refpc(pc, "on_p2s_recv_msg");
     err = grpc_call_start_batch(pc->p2s, &op, 1,
                                 new_closure(on_p2s_recv_msg, pc), NULL);
@@ -278,7 +278,7 @@ static void on_p2s_recv_msg(void *arg, int success) {
     op.op = GRPC_OP_SEND_MESSAGE;
     op.flags = 0;
     op.reserved = NULL;
-    op.data.send_message = pc->p2s_msg;
+    op.data.send_message.send_message = pc->p2s_msg;
     refpc(pc, "on_c2p_sent_message");
     err = grpc_call_start_batch(pc->c2p, &op, 1,
                                 new_closure(on_c2p_sent_message, pc), NULL);
@@ -347,7 +347,8 @@ static void on_new_call(void *arg, int success) {
 
     op.op = GRPC_OP_RECV_INITIAL_METADATA;
     op.flags = 0;
-    op.data.recv_initial_metadata = &pc->p2s_initial_metadata;
+    op.data.recv_initial_metadata.recv_initial_metadata =
+        &pc->p2s_initial_metadata;
     refpc(pc, "on_p2s_recv_initial_metadata");
     err = grpc_call_start_batch(
         pc->p2s, &op, 1, new_closure(on_p2s_recv_initial_metadata, pc), NULL);
@@ -364,7 +365,7 @@ static void on_new_call(void *arg, int success) {
 
     op.op = GRPC_OP_RECV_MESSAGE;
     op.flags = 0;
-    op.data.recv_message = &pc->c2p_msg;
+    op.data.recv_message.recv_message = &pc->c2p_msg;
     refpc(pc, "on_c2p_recv_msg");
     err = grpc_call_start_batch(pc->c2p, &op, 1,
                                 new_closure(on_c2p_recv_msg, pc), NULL);
@@ -372,7 +373,7 @@ static void on_new_call(void *arg, int success) {
 
     op.op = GRPC_OP_RECV_MESSAGE;
     op.flags = 0;
-    op.data.recv_message = &pc->p2s_msg;
+    op.data.recv_message.recv_message = &pc->p2s_msg;
     refpc(pc, "on_p2s_recv_msg");
     err = grpc_call_start_batch(pc->p2s, &op, 1,
                                 new_closure(on_p2s_recv_msg, pc), NULL);
diff --git a/test/core/end2end/fuzzers/api_fuzzer.c b/test/core/end2end/fuzzers/api_fuzzer.c
index 200a51858a..07f282b5f5 100644
--- a/test/core/end2end/fuzzers/api_fuzzer.c
+++ b/test/core/end2end/fuzzers/api_fuzzer.c
@@ -933,7 +933,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
                 ok = false;
               } else {
                 has_ops |= 1 << GRPC_OP_SEND_MESSAGE;
-                g_active_call->send_message = op->data.send_message =
+                g_active_call->send_message =
+                    op->data.send_message.send_message =
                     read_message(&inp);
               }
               break;
@@ -956,13 +957,13 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
             case GRPC_OP_RECV_INITIAL_METADATA:
               op->op = GRPC_OP_RECV_INITIAL_METADATA;
               has_ops |= 1 << GRPC_OP_RECV_INITIAL_METADATA;
-              op->data.recv_initial_metadata =
+              op->data.recv_initial_metadata.recv_initial_metadata =
                   &g_active_call->recv_initial_metadata;
               break;
             case GRPC_OP_RECV_MESSAGE:
               op->op = GRPC_OP_RECV_MESSAGE;
               has_ops |= 1 << GRPC_OP_RECV_MESSAGE;
-              op->data.recv_message = &g_active_call->recv_message;
+              op->data.recv_message.recv_message = &g_active_call->recv_message;
               break;
             case GRPC_OP_RECV_STATUS_ON_CLIENT:
               op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
diff --git a/test/core/end2end/fuzzers/client_fuzzer.c b/test/core/end2end/fuzzers/client_fuzzer.c
index 26b520885b..ab708bc7d8 100644
--- a/test/core/end2end/fuzzers/client_fuzzer.c
+++ b/test/core/end2end/fuzzers/client_fuzzer.c
@@ -97,12 +97,12 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/invalid_call_argument_test.c b/test/core/end2end/invalid_call_argument_test.c
index d974d2c8ff..5ce7ca0243 100644
--- a/test/core/end2end/invalid_call_argument_test.c
+++ b/test/core/end2end/invalid_call_argument_test.c
@@ -237,7 +237,7 @@ static void test_send_null_message() {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = NULL;
+  op->data.send_message.send_message = NULL;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -263,12 +263,12 @@ static void test_send_messages_at_the_same_time() {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = tag(2);
+  op->data.send_message.send_message = tag(2);
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -306,7 +306,8 @@ static void test_receive_initial_metadata_twice_at_client() {
   prepare_test(1);
   op = g_state.ops;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &g_state.initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata =
+      &g_state.initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -317,7 +318,8 @@ static void test_receive_initial_metadata_twice_at_client() {
   cq_verify(g_state.cqv);
   op = g_state.ops;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &g_state.initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata =
+      &g_state.initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -335,7 +337,7 @@ static void test_receive_message_with_invalid_flags() {
   prepare_test(1);
   op = g_state.ops;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &payload;
+  op->data.recv_message.recv_message = &payload;
   op->flags = 1;
   op->reserved = NULL;
   op++;
@@ -353,12 +355,12 @@ static void test_receive_two_messages_at_the_same_time() {
   prepare_test(1);
   op = g_state.ops;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &payload;
+  op->data.recv_message.recv_message = &payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &payload;
+  op->data.recv_message.recv_message = &payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/authority_not_supported.c b/test/core/end2end/tests/authority_not_supported.c
index 705970f6ca..b9a1d889a8 100644
--- a/test/core/end2end/tests/authority_not_supported.c
+++ b/test/core/end2end/tests/authority_not_supported.c
@@ -135,7 +135,7 @@ static void test_with_authority_header(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -144,12 +144,12 @@ static void test_with_authority_header(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/bad_hostname.c b/test/core/end2end/tests/bad_hostname.c
index e0c7ac7c02..054a1f446d 100644
--- a/test/core/end2end/tests/bad_hostname.c
+++ b/test/core/end2end/tests/bad_hostname.c
@@ -133,7 +133,7 @@ static void simple_request_body(grpc_end2end_test_fixture f) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/binary_metadata.c b/test/core/end2end/tests/binary_metadata.c
index dd7a8a9ad3..2b76cc257a 100644
--- a/test/core/end2end/tests/binary_metadata.c
+++ b/test/core/end2end/tests/binary_metadata.c
@@ -168,7 +168,7 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -177,12 +177,12 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -213,7 +213,7 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -231,7 +231,7 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/call_creds.c b/test/core/end2end/tests/call_creds.c
index 606938fff6..cb0c215db4 100644
--- a/test/core/end2end/tests/call_creds.c
+++ b/test/core/end2end/tests/call_creds.c
@@ -203,7 +203,7 @@ static void request_response_with_payload_and_call_creds(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -212,12 +212,12 @@ static void request_response_with_payload_and_call_creds(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -259,7 +259,7 @@ static void request_response_with_payload_and_call_creds(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -277,7 +277,7 @@ static void request_response_with_payload_and_call_creds(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -435,7 +435,7 @@ static void test_request_with_server_rejecting_client_creds(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -444,12 +444,12 @@ static void test_request_with_server_rejecting_client_creds(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/cancel_after_accept.c b/test/core/end2end/tests/cancel_after_accept.c
index a8e310c683..b14d9daf22 100644
--- a/test/core/end2end/tests/cancel_after_accept.c
+++ b/test/core/end2end/tests/cancel_after_accept.c
@@ -180,17 +180,17 @@ static void test_cancel_after_accept(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -206,7 +206,7 @@ static void test_cancel_after_accept(grpc_end2end_test_config config,
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -216,7 +216,7 @@ static void test_cancel_after_accept(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/cancel_after_client_done.c b/test/core/end2end/tests/cancel_after_client_done.c
index 7742f9d179..b713278ae5 100644
--- a/test/core/end2end/tests/cancel_after_client_done.c
+++ b/test/core/end2end/tests/cancel_after_client_done.c
@@ -154,7 +154,7 @@ static void test_cancel_after_accept_and_writes_closed(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -163,12 +163,12 @@ static void test_cancel_after_accept_and_writes_closed(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -184,7 +184,7 @@ static void test_cancel_after_accept_and_writes_closed(
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -199,7 +199,7 @@ static void test_cancel_after_accept_and_writes_closed(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/cancel_after_invoke.c b/test/core/end2end/tests/cancel_after_invoke.c
index c3c5418f20..b68f3245b3 100644
--- a/test/core/end2end/tests/cancel_after_invoke.c
+++ b/test/core/end2end/tests/cancel_after_invoke.c
@@ -148,7 +148,7 @@ static void test_cancel_after_invoke(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -157,12 +157,12 @@ static void test_cancel_after_invoke(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/cancel_before_invoke.c b/test/core/end2end/tests/cancel_before_invoke.c
index d4842829c0..9174fcb655 100644
--- a/test/core/end2end/tests/cancel_before_invoke.c
+++ b/test/core/end2end/tests/cancel_before_invoke.c
@@ -148,7 +148,7 @@ static void test_cancel_before_invoke(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -157,12 +157,12 @@ static void test_cancel_before_invoke(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/cancel_with_status.c b/test/core/end2end/tests/cancel_with_status.c
index 3aecaf7159..071c07887c 100644
--- a/test/core/end2end/tests/cancel_with_status.c
+++ b/test/core/end2end/tests/cancel_with_status.c
@@ -133,7 +133,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/compressed_payload.c b/test/core/end2end/tests/compressed_payload.c
index d7efe7747b..f3b0625380 100644
--- a/test/core/end2end/tests/compressed_payload.c
+++ b/test/core/end2end/tests/compressed_payload.c
@@ -174,7 +174,7 @@ static void request_for_disabled_algorithm(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = send_flags_bitmask;
   op->reserved = NULL;
   op++;
@@ -183,7 +183,7 @@ static void request_for_disabled_algorithm(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -212,7 +212,7 @@ static void request_for_disabled_algorithm(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -354,7 +354,7 @@ static void request_with_payload_template(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -412,12 +412,12 @@ static void request_with_payload_template(
     memset(ops, 0, sizeof(ops));
     op = ops;
     op->op = GRPC_OP_SEND_MESSAGE;
-    op->data.send_message = request_payload;
+    op->data.send_message.send_message = request_payload;
     op->flags = client_send_flags_bitmask;
     op->reserved = NULL;
     op++;
     op->op = GRPC_OP_RECV_MESSAGE;
-    op->data.recv_message = &response_payload_recv;
+    op->data.recv_message.recv_message = &response_payload_recv;
     op->flags = 0;
     op->reserved = NULL;
     op++;
@@ -427,7 +427,7 @@ static void request_with_payload_template(
     memset(ops, 0, sizeof(ops));
     op = ops;
     op->op = GRPC_OP_RECV_MESSAGE;
-    op->data.recv_message = &request_payload_recv;
+    op->data.recv_message.recv_message = &request_payload_recv;
     op->flags = 0;
     op->reserved = NULL;
     op++;
@@ -444,7 +444,7 @@ static void request_with_payload_template(
     memset(ops, 0, sizeof(ops));
     op = ops;
     op->op = GRPC_OP_SEND_MESSAGE;
-    op->data.send_message = response_payload;
+    op->data.send_message.send_message = response_payload;
     op->flags = 0;
     op->reserved = NULL;
     op++;
diff --git a/test/core/end2end/tests/default_host.c b/test/core/end2end/tests/default_host.c
index 208e31697e..21dd04f069 100644
--- a/test/core/end2end/tests/default_host.c
+++ b/test/core/end2end/tests/default_host.c
@@ -141,7 +141,7 @@ static void simple_request_body(grpc_end2end_test_fixture f) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/disappearing_server.c b/test/core/end2end/tests/disappearing_server.c
index 8ebf7e643e..4fa06755e5 100644
--- a/test/core/end2end/tests/disappearing_server.c
+++ b/test/core/end2end/tests/disappearing_server.c
@@ -120,7 +120,7 @@ static void do_request_and_shutdown_server(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/filter_call_init_fails.c b/test/core/end2end/tests/filter_call_init_fails.c
index ac9d2dd2fe..1ecf1ef2a8 100644
--- a/test/core/end2end/tests/filter_call_init_fails.c
+++ b/test/core/end2end/tests/filter_call_init_fails.c
@@ -148,7 +148,7 @@ static void test_request(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -157,7 +157,7 @@ static void test_request(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/filter_causes_close.c b/test/core/end2end/tests/filter_causes_close.c
index 45f623c5c7..0991431eac 100644
--- a/test/core/end2end/tests/filter_causes_close.c
+++ b/test/core/end2end/tests/filter_causes_close.c
@@ -144,7 +144,7 @@ static void test_request(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -153,7 +153,7 @@ static void test_request(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/filter_latency.c b/test/core/end2end/tests/filter_latency.c
index dbb5c8dcd9..5f412e1f1c 100644
--- a/test/core/end2end/tests/filter_latency.c
+++ b/test/core/end2end/tests/filter_latency.c
@@ -156,7 +156,7 @@ static void test_request(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -165,7 +165,7 @@ static void test_request(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/graceful_server_shutdown.c b/test/core/end2end/tests/graceful_server_shutdown.c
index 5fecadbe44..172618e1df 100644
--- a/test/core/end2end/tests/graceful_server_shutdown.c
+++ b/test/core/end2end/tests/graceful_server_shutdown.c
@@ -135,7 +135,7 @@ static void test_early_server_shutdown_finishes_inflight_calls(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/high_initial_seqno.c b/test/core/end2end/tests/high_initial_seqno.c
index 01a4909ccd..bb981f7fb5 100644
--- a/test/core/end2end/tests/high_initial_seqno.c
+++ b/test/core/end2end/tests/high_initial_seqno.c
@@ -140,7 +140,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/hpack_size.c b/test/core/end2end/tests/hpack_size.c
index cec8b2faae..ccb8f71e4c 100644
--- a/test/core/end2end/tests/hpack_size.c
+++ b/test/core/end2end/tests/hpack_size.c
@@ -293,7 +293,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/idempotent_request.c b/test/core/end2end/tests/idempotent_request.c
index 4f6d3bb808..475303e180 100644
--- a/test/core/end2end/tests/idempotent_request.c
+++ b/test/core/end2end/tests/idempotent_request.c
@@ -144,7 +144,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/invoke_large_request.c b/test/core/end2end/tests/invoke_large_request.c
index 24abfa2ea0..10459a35c4 100644
--- a/test/core/end2end/tests/invoke_large_request.c
+++ b/test/core/end2end/tests/invoke_large_request.c
@@ -163,7 +163,7 @@ static void test_invoke_large_request(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -172,12 +172,12 @@ static void test_invoke_large_request(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -207,7 +207,7 @@ static void test_invoke_large_request(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -225,7 +225,7 @@ static void test_invoke_large_request(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/large_metadata.c b/test/core/end2end/tests/large_metadata.c
index 69b4b24b06..2a7f49ccfe 100644
--- a/test/core/end2end/tests/large_metadata.c
+++ b/test/core/end2end/tests/large_metadata.c
@@ -153,7 +153,7 @@ static void test_request_with_large_metadata(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -162,7 +162,7 @@ static void test_request_with_large_metadata(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -194,7 +194,7 @@ static void test_request_with_large_metadata(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/load_reporting_hook.c b/test/core/end2end/tests/load_reporting_hook.c
index ae5c270629..c8de069704 100644
--- a/test/core/end2end/tests/load_reporting_hook.c
+++ b/test/core/end2end/tests/load_reporting_hook.c
@@ -171,7 +171,7 @@ static void request_response_with_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -180,12 +180,12 @@ static void request_response_with_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -215,7 +215,7 @@ static void request_response_with_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -233,7 +233,7 @@ static void request_response_with_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/max_concurrent_streams.c b/test/core/end2end/tests/max_concurrent_streams.c
index 9338bc5f0d..4582178958 100644
--- a/test/core/end2end/tests/max_concurrent_streams.c
+++ b/test/core/end2end/tests/max_concurrent_streams.c
@@ -136,7 +136,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -300,7 +300,8 @@ static void test_max_concurrent_streams(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv1;
+  op->data.recv_initial_metadata.recv_initial_metadata =
+      &initial_metadata_recv1;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -332,7 +333,8 @@ static void test_max_concurrent_streams(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv1;
+  op->data.recv_initial_metadata.recv_initial_metadata =
+      &initial_metadata_recv1;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/max_message_length.c b/test/core/end2end/tests/max_message_length.c
index 4a6ef44bb3..57d4f1c197 100644
--- a/test/core/end2end/tests/max_message_length.c
+++ b/test/core/end2end/tests/max_message_length.c
@@ -196,7 +196,7 @@ static void test_max_message_length_on_request(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -205,7 +205,7 @@ static void test_max_message_length_on_request(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -241,7 +241,7 @@ static void test_max_message_length_on_request(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &recv_payload;
+  op->data.recv_message.recv_message = &recv_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -376,12 +376,12 @@ static void test_max_message_length_on_response(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &recv_payload;
+  op->data.recv_message.recv_message = &recv_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -416,7 +416,7 @@ static void test_max_message_length_on_response(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/negative_deadline.c b/test/core/end2end/tests/negative_deadline.c
index 929777d39e..61a985819e 100644
--- a/test/core/end2end/tests/negative_deadline.c
+++ b/test/core/end2end/tests/negative_deadline.c
@@ -133,7 +133,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/network_status_change.c b/test/core/end2end/tests/network_status_change.c
index 2ebda2ccb8..dc855b7940 100644
--- a/test/core/end2end/tests/network_status_change.c
+++ b/test/core/end2end/tests/network_status_change.c
@@ -142,7 +142,7 @@ static void test_invoke_network_status_change(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -151,7 +151,7 @@ static void test_invoke_network_status_change(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -179,7 +179,7 @@ static void test_invoke_network_status_change(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/no_logging.c b/test/core/end2end/tests/no_logging.c
index 54614cb029..497ed05cac 100644
--- a/test/core/end2end/tests/no_logging.c
+++ b/test/core/end2end/tests/no_logging.c
@@ -171,7 +171,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/payload.c b/test/core/end2end/tests/payload.c
index 4a88c5f2a8..e39b513ffd 100644
--- a/test/core/end2end/tests/payload.c
+++ b/test/core/end2end/tests/payload.c
@@ -161,7 +161,7 @@ static void request_response_with_payload(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -170,12 +170,12 @@ static void request_response_with_payload(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -205,7 +205,7 @@ static void request_response_with_payload(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -223,7 +223,7 @@ static void request_response_with_payload(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/ping_pong_streaming.c b/test/core/end2end/tests/ping_pong_streaming.c
index 0a1566e9c2..bd6b53ff19 100644
--- a/test/core/end2end/tests/ping_pong_streaming.c
+++ b/test/core/end2end/tests/ping_pong_streaming.c
@@ -144,7 +144,7 @@ static void test_pingpong_streaming(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -188,12 +188,12 @@ static void test_pingpong_streaming(grpc_end2end_test_config config,
     memset(ops, 0, sizeof(ops));
     op = ops;
     op->op = GRPC_OP_SEND_MESSAGE;
-    op->data.send_message = request_payload;
+    op->data.send_message.send_message = request_payload;
     op->flags = 0;
     op->reserved = NULL;
     op++;
     op->op = GRPC_OP_RECV_MESSAGE;
-    op->data.recv_message = &response_payload_recv;
+    op->data.recv_message.recv_message = &response_payload_recv;
     op->flags = 0;
     op->reserved = NULL;
     op++;
@@ -203,7 +203,7 @@ static void test_pingpong_streaming(grpc_end2end_test_config config,
     memset(ops, 0, sizeof(ops));
     op = ops;
     op->op = GRPC_OP_RECV_MESSAGE;
-    op->data.recv_message = &request_payload_recv;
+    op->data.recv_message.recv_message = &request_payload_recv;
     op->flags = 0;
     op->reserved = NULL;
     op++;
@@ -215,7 +215,7 @@ static void test_pingpong_streaming(grpc_end2end_test_config config,
     memset(ops, 0, sizeof(ops));
     op = ops;
     op->op = GRPC_OP_SEND_MESSAGE;
-    op->data.send_message = response_payload;
+    op->data.send_message.send_message = response_payload;
     op->flags = 0;
     op->reserved = NULL;
     op++;
diff --git a/test/core/end2end/tests/registered_call.c b/test/core/end2end/tests/registered_call.c
index 6594b420b9..ea1b4cf524 100644
--- a/test/core/end2end/tests/registered_call.c
+++ b/test/core/end2end/tests/registered_call.c
@@ -136,7 +136,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/request_with_flags.c b/test/core/end2end/tests/request_with_flags.c
index 9c18e155f3..bafe6f605a 100644
--- a/test/core/end2end/tests/request_with_flags.c
+++ b/test/core/end2end/tests/request_with_flags.c
@@ -140,7 +140,7 @@ static void test_invoke_request_with_flags(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = flags_for_op[op->op];
   op->reserved = NULL;
   op++;
@@ -149,7 +149,7 @@ static void test_invoke_request_with_flags(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = flags_for_op[op->op];
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/request_with_payload.c b/test/core/end2end/tests/request_with_payload.c
index c84e3ac5b5..58f7279b0d 100644
--- a/test/core/end2end/tests/request_with_payload.c
+++ b/test/core/end2end/tests/request_with_payload.c
@@ -139,7 +139,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -148,7 +148,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -177,7 +177,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/resource_quota_server.c b/test/core/end2end/tests/resource_quota_server.c
index c919faea89..96abc1cc76 100644
--- a/test/core/end2end/tests/resource_quota_server.c
+++ b/test/core/end2end/tests/resource_quota_server.c
@@ -201,7 +201,7 @@ void resource_quota_server(grpc_end2end_test_config config) {
     op->reserved = NULL;
     op++;
     op->op = GRPC_OP_SEND_MESSAGE;
-    op->data.send_message = request_payload;
+    op->data.send_message.send_message = request_payload;
     op->flags = 0;
     op->reserved = NULL;
     op++;
@@ -210,7 +210,8 @@ void resource_quota_server(grpc_end2end_test_config config) {
     op->reserved = NULL;
     op++;
     op->op = GRPC_OP_RECV_INITIAL_METADATA;
-    op->data.recv_initial_metadata = &initial_metadata_recv[i];
+    op->data.recv_initial_metadata.recv_initial_metadata =
+        &initial_metadata_recv[i];
     op->flags = 0;
     op->reserved = NULL;
     op++;
@@ -277,7 +278,7 @@ void resource_quota_server(grpc_end2end_test_config config) {
       op->reserved = NULL;
       op++;
       op->op = GRPC_OP_RECV_MESSAGE;
-      op->data.recv_message = &request_payload_recv[call_id];
+      op->data.recv_message.recv_message = &request_payload_recv[call_id];
       op->flags = 0;
       op->reserved = NULL;
       op++;
diff --git a/test/core/end2end/tests/server_finishes_request.c b/test/core/end2end/tests/server_finishes_request.c
index 3bb25fd924..6541815125 100644
--- a/test/core/end2end/tests/server_finishes_request.c
+++ b/test/core/end2end/tests/server_finishes_request.c
@@ -134,7 +134,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/shutdown_finishes_calls.c b/test/core/end2end/tests/shutdown_finishes_calls.c
index b80a2e35f2..608e97e338 100644
--- a/test/core/end2end/tests/shutdown_finishes_calls.c
+++ b/test/core/end2end/tests/shutdown_finishes_calls.c
@@ -128,7 +128,7 @@ static void test_early_server_shutdown_finishes_inflight_calls(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/simple_cacheable_request.c b/test/core/end2end/tests/simple_cacheable_request.c
index 2c229b08fe..269a40de9c 100644
--- a/test/core/end2end/tests/simple_cacheable_request.c
+++ b/test/core/end2end/tests/simple_cacheable_request.c
@@ -155,7 +155,7 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -164,12 +164,12 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -200,7 +200,7 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -218,7 +218,7 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/simple_delayed_request.c b/test/core/end2end/tests/simple_delayed_request.c
index 414a03d98b..be9f9bffac 100644
--- a/test/core/end2end/tests/simple_delayed_request.c
+++ b/test/core/end2end/tests/simple_delayed_request.c
@@ -129,7 +129,7 @@ static void simple_delayed_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/simple_metadata.c b/test/core/end2end/tests/simple_metadata.c
index 5490cc2b75..c9e571e655 100644
--- a/test/core/end2end/tests/simple_metadata.c
+++ b/test/core/end2end/tests/simple_metadata.c
@@ -152,7 +152,7 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -161,12 +161,12 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -197,7 +197,7 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -215,7 +215,7 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/simple_request.c b/test/core/end2end/tests/simple_request.c
index 2dea5d6af2..787ad40057 100644
--- a/test/core/end2end/tests/simple_request.c
+++ b/test/core/end2end/tests/simple_request.c
@@ -144,7 +144,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/streaming_error_response.c b/test/core/end2end/tests/streaming_error_response.c
index 583bc9268f..6fc6d75911 100644
--- a/test/core/end2end/tests/streaming_error_response.c
+++ b/test/core/end2end/tests/streaming_error_response.c
@@ -144,10 +144,10 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
   op->op = GRPC_OP_SEND_CLOSE_FROM_CLIENT;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload1_recv;
+  op->data.recv_message.recv_message = &response_payload1_recv;
   op++;
   if (request_status_early) {
     op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
@@ -172,7 +172,7 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
   op->data.send_initial_metadata.count = 0;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload1;
+  op->data.send_message.send_message = response_payload1;
   op++;
   error = grpc_call_start_batch(s, ops, (size_t)(op - ops), tag(102), NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
@@ -183,7 +183,7 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload2;
+  op->data.send_message.send_message = response_payload2;
   op++;
   error = grpc_call_start_batch(s, ops, (size_t)(op - ops), tag(103), NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
@@ -211,7 +211,7 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
     memset(ops, 0, sizeof(ops));
     op = ops;
     op->op = GRPC_OP_RECV_MESSAGE;
-    op->data.recv_message = &response_payload2_recv;
+    op->data.recv_message.recv_message = &response_payload2_recv;
     op++;
     error = grpc_call_start_batch(c, ops, (size_t)(op - ops), tag(2), NULL);
     GPR_ASSERT(GRPC_CALL_OK == error);
diff --git a/test/core/end2end/tests/trailing_metadata.c b/test/core/end2end/tests/trailing_metadata.c
index 9fd4fbc052..a44ed77a82 100644
--- a/test/core/end2end/tests/trailing_metadata.c
+++ b/test/core/end2end/tests/trailing_metadata.c
@@ -155,7 +155,7 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -164,12 +164,12 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -200,7 +200,7 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -218,7 +218,7 @@ static void test_request_response_with_metadata_and_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = response_payload;
+  op->data.send_message.send_message = response_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/core/end2end/tests/write_buffering.c b/test/core/end2end/tests/write_buffering.c
index 856e9f0306..ee95338de1 100644
--- a/test/core/end2end/tests/write_buffering.c
+++ b/test/core/end2end/tests/write_buffering.c
@@ -146,7 +146,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -163,7 +163,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload1;
+  op->data.send_message.send_message = request_payload1;
   op->flags = GRPC_WRITE_BUFFER_HINT;
   op++;
   error = grpc_call_start_batch(c, ops, (size_t)(op - ops), tag(3), NULL);
@@ -181,7 +181,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv1;
+  op->data.recv_message.recv_message = &request_payload_recv1;
   op++;
   error = grpc_call_start_batch(s, ops, (size_t)(op - ops), tag(103), NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
@@ -195,7 +195,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload2;
+  op->data.send_message.send_message = request_payload2;
   op->flags = 0;
   op++;
   error = grpc_call_start_batch(c, ops, (size_t)(op - ops), tag(4), NULL);
@@ -210,7 +210,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv2;
+  op->data.recv_message.recv_message = &request_payload_recv2;
   op++;
   error = grpc_call_start_batch(s, ops, (size_t)(op - ops), tag(104), NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
diff --git a/test/core/end2end/tests/write_buffering_at_end.c b/test/core/end2end/tests/write_buffering_at_end.c
index 43aefcbdbc..9b203ea262 100644
--- a/test/core/end2end/tests/write_buffering_at_end.c
+++ b/test/core/end2end/tests/write_buffering_at_end.c
@@ -143,7 +143,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -160,7 +160,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = request_payload;
+  op->data.send_message.send_message = request_payload;
   op->flags = GRPC_WRITE_BUFFER_HINT;
   op++;
   error = grpc_call_start_batch(c, ops, (size_t)(op - ops), tag(3), NULL);
@@ -178,7 +178,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv1;
+  op->data.recv_message.recv_message = &request_payload_recv1;
   op++;
   error = grpc_call_start_batch(s, ops, (size_t)(op - ops), tag(103), NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
@@ -205,7 +205,7 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   memset(ops, 0, sizeof(ops));
   op = ops;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv2;
+  op->data.recv_message.recv_message = &request_payload_recv2;
   op++;
   error = grpc_call_start_batch(s, ops, (size_t)(op - ops), tag(104), NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
diff --git a/test/core/fling/client.c b/test/core/fling/client.c
index e717b7f7fe..e1a4630094 100644
--- a/test/core/fling/client.c
+++ b/test/core/fling/client.c
@@ -72,15 +72,15 @@ static void init_ping_pong_request(void) {
   op->data.send_initial_metadata.count = 0;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
-  op->data.send_message = the_buffer;
+  op->data.send_message.send_message = the_buffer;
   op++;
   op->op = GRPC_OP_SEND_CLOSE_FROM_CLIENT;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op++;
   op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
@@ -115,7 +115,8 @@ static void init_ping_pong_stream(void) {
   stream_init_ops[0].op = GRPC_OP_SEND_INITIAL_METADATA;
   stream_init_ops[0].data.send_initial_metadata.count = 0;
   stream_init_ops[1].op = GRPC_OP_RECV_INITIAL_METADATA;
-  stream_init_ops[1].data.recv_initial_metadata = &initial_metadata_recv;
+  stream_init_ops[1].data.recv_initial_metadata.recv_initial_metadata =
+      &initial_metadata_recv;
   error = grpc_call_start_batch(call, stream_init_ops, 2, (void *)1, NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
   grpc_completion_queue_next(cq, gpr_inf_future(GPR_CLOCK_REALTIME), NULL);
@@ -123,9 +124,9 @@ static void init_ping_pong_stream(void) {
   grpc_metadata_array_init(&initial_metadata_recv);
 
   stream_step_ops[0].op = GRPC_OP_SEND_MESSAGE;
-  stream_step_ops[0].data.send_message = the_buffer;
+  stream_step_ops[0].data.send_message.send_message = the_buffer;
   stream_step_ops[1].op = GRPC_OP_RECV_MESSAGE;
-  stream_step_ops[1].data.recv_message = &response_payload_recv;
+  stream_step_ops[1].data.recv_message.recv_message = &response_payload_recv;
 }
 
 static void step_ping_pong_stream(void) {
diff --git a/test/core/fling/server.c b/test/core/fling/server.c
index fd446f1128..79e5e35211 100644
--- a/test/core/fling/server.c
+++ b/test/core/fling/server.c
@@ -107,13 +107,13 @@ static void handle_unary_method(void) {
   op->data.send_initial_metadata.count = 0;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &terminal_buffer;
+  op->data.recv_message.recv_message = &terminal_buffer;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
   if (payload_buffer == NULL) {
     gpr_log(GPR_INFO, "NULL payload buffer !!!");
   }
-  op->data.send_message = payload_buffer;
+  op->data.send_message.send_message = payload_buffer;
   op++;
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
@@ -144,7 +144,7 @@ static void start_read_op(int t) {
   grpc_call_error error;
   /* Starting read at server */
   read_op.op = GRPC_OP_RECV_MESSAGE;
-  read_op.data.recv_message = &payload_buffer;
+  read_op.data.recv_message.recv_message = &payload_buffer;
   error = grpc_call_start_batch(call, &read_op, 1, tag(t), NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
 }
@@ -157,7 +157,7 @@ static void start_write_op(void) {
   if (payload_buffer == NULL) {
     gpr_log(GPR_INFO, "NULL payload buffer !!!");
   }
-  write_op.data.send_message = payload_buffer;
+  write_op.data.send_message.send_message = payload_buffer;
   error = grpc_call_start_batch(call, &write_op, 1, tagarg, NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
 }
diff --git a/test/core/memory_usage/client.c b/test/core/memory_usage/client.c
index f4432bf572..827a39540d 100644
--- a/test/core/memory_usage/client.c
+++ b/test/core/memory_usage/client.c
@@ -82,7 +82,8 @@ static void init_ping_pong_request(int call_idx) {
   op->flags = GRPC_INITIAL_METADATA_WAIT_FOR_READY;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &calls[call_idx].initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata =
+      &calls[call_idx].initial_metadata_recv;
   op++;
 
   calls[call_idx].call = grpc_channel_create_call(
@@ -139,10 +140,11 @@ static struct grpc_memory_counters send_snapshot_request(
   op->op = GRPC_OP_SEND_CLOSE_FROM_CLIENT;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &calls[call_idx].initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata =
+      &calls[call_idx].initial_metadata_recv;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &response_payload_recv;
+  op->data.recv_message.recv_message = &response_payload_recv;
   op++;
   op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
   op->data.recv_status_on_client.trailing_metadata =
diff --git a/test/core/memory_usage/server.c b/test/core/memory_usage/server.c
index c0710930b0..cd7f2aabdd 100644
--- a/test/core/memory_usage/server.c
+++ b/test/core/memory_usage/server.c
@@ -129,13 +129,13 @@ static void send_snapshot(void *tag, struct grpc_memory_counters *snapshot) {
   op->data.send_initial_metadata.count = 0;
   op++;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &terminal_buffer;
+  op->data.recv_message.recv_message = &terminal_buffer;
   op++;
   op->op = GRPC_OP_SEND_MESSAGE;
   if (payload_buffer == NULL) {
     gpr_log(GPR_INFO, "NULL payload buffer !!!");
   }
-  op->data.send_message = payload_buffer;
+  op->data.send_message.send_message = payload_buffer;
   op++;
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
diff --git a/test/core/surface/lame_client_test.c b/test/core/surface/lame_client_test.c
index b6db6a6b08..b78361aacb 100644
--- a/test/core/surface/lame_client_test.c
+++ b/test/core/surface/lame_client_test.c
@@ -125,7 +125,7 @@ int main(int argc, char **argv) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
diff --git a/test/cpp/grpclb/grpclb_test.cc b/test/cpp/grpclb/grpclb_test.cc
index de304b9f89..3637190b6d 100644
--- a/test/cpp/grpclb/grpclb_test.cc
+++ b/test/cpp/grpclb/grpclb_test.cc
@@ -213,7 +213,7 @@ static void start_lb_server(server_fixture *sf, int *ports, size_t nports,
   // receive request for backends
   op = ops;
   op->op = GRPC_OP_RECV_MESSAGE;
-  op->data.recv_message = &request_payload_recv;
+  op->data.recv_message.recv_message = &request_payload_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -268,7 +268,7 @@ static void start_lb_server(server_fixture *sf, int *ports, size_t nports,
     response_payload = grpc_raw_byte_buffer_create(&response_payload_slice, 1);
     op = ops;
     op->op = GRPC_OP_SEND_MESSAGE;
-    op->data.send_message = response_payload;
+    op->data.send_message.send_message = response_payload;
     op->flags = 0;
     op->reserved = NULL;
     op++;
@@ -372,7 +372,7 @@ static void start_backend_server(server_fixture *sf) {
     while (!exit) {
       op = ops;
       op->op = GRPC_OP_RECV_MESSAGE;
-      op->data.recv_message = &request_payload_recv;
+      op->data.recv_message.recv_message = &request_payload_recv;
       op->flags = 0;
       op->reserved = NULL;
       op++;
@@ -401,7 +401,7 @@ static void start_backend_server(server_fixture *sf) {
             grpc_raw_byte_buffer_create(&response_payload_slice, 1);
         op = ops;
         op->op = GRPC_OP_SEND_MESSAGE;
-        op->data.send_message = response_payload;
+        op->data.send_message.send_message = response_payload;
         op->flags = 0;
         op->reserved = NULL;
         op++;
@@ -489,7 +489,7 @@ static void perform_request(client_fixture *cf) {
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
-  op->data.recv_initial_metadata = &initial_metadata_recv;
+  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -509,12 +509,12 @@ static void perform_request(client_fixture *cf) {
 
     op = ops;
     op->op = GRPC_OP_SEND_MESSAGE;
-    op->data.send_message = request_payload;
+    op->data.send_message.send_message = request_payload;
     op->flags = 0;
     op->reserved = NULL;
     op++;
     op->op = GRPC_OP_RECV_MESSAGE;
-    op->data.recv_message = &response_payload_recv;
+    op->data.recv_message.recv_message = &response_payload_recv;
     op->flags = 0;
     op->reserved = NULL;
     op++;