Merge pull request #6875 from y-zeng/log_check

Add format check for gpr_log and gpr_asprintf, add gpr_strpad 

39 files changed, 186 insertions, 99 deletions

diff --git a/include/grpc/impl/codegen/log.h b/include/grpc/impl/codegen/log.h
index aa86fc4c17..e5010c29da 100644
--- a/include/grpc/impl/codegen/log.h
+++ b/include/grpc/impl/codegen/log.h
@@ -34,6 +34,7 @@
 #ifndef GRPC_IMPL_CODEGEN_LOG_H
 #define GRPC_IMPL_CODEGEN_LOG_H
 
+#include <inttypes.h>
 #include <stdarg.h>
 #include <stdlib.h> /* for abort() */
 
@@ -74,7 +75,7 @@ const char *gpr_log_severity_string(gpr_log_severity severity);
 /* Log a message. It's advised to use GPR_xxx above to generate the context
  * for each message */
 GPRAPI void gpr_log(const char *file, int line, gpr_log_severity severity,
-                    const char *format, ...);
+                    const char *format, ...) GPRC_PRINT_FORMAT_CHECK(4, 5);
 
 GPRAPI void gpr_log_message(const char *file, int line,
                             gpr_log_severity severity, const char *message);
diff --git a/include/grpc/impl/codegen/port_platform.h b/include/grpc/impl/codegen/port_platform.h
index 7fff36cb78..9640ab6008 100644
--- a/include/grpc/impl/codegen/port_platform.h
+++ b/include/grpc/impl/codegen/port_platform.h
@@ -434,6 +434,15 @@ typedef unsigned __int64 uint64_t;
 #endif
 #endif
 
+#ifndef GPRC_PRINT_FORMAT_CHECK
+#ifdef __GNUC__
+#define GPRC_PRINT_FORMAT_CHECK(FORMAT_STR, ARGS) \
+  __attribute__((format(printf, FORMAT_STR, ARGS)))
+#else
+#define GPRC_PRINT_FORMAT_CHECK(FORMAT_STR, ARGS)
+#endif
+#endif /* GPRC_PRINT_FORMAT_CHECK */
+
 #if GPR_FORBID_UNREACHABLE_CODE
 #define GPR_UNREACHABLE_CODE(STATEMENT)
 #else
diff --git a/include/grpc/support/string_util.h b/include/grpc/support/string_util.h
index f981bc0db0..952cbfc26b 100644
--- a/include/grpc/support/string_util.h
+++ b/include/grpc/support/string_util.h
@@ -54,7 +54,8 @@ GPRAPI char *gpr_strdup(const char *src);
 
    On error, returns -1 and sets *strp to NULL. If the format string is bad,
    the result is undefined. */
-GPRAPI int gpr_asprintf(char **strp, const char *format, ...);
+GPRAPI int gpr_asprintf(char **strp, const char *format, ...)
+    GPRC_PRINT_FORMAT_CHECK(2, 3);
 
 #ifdef __cplusplus
 }
diff --git a/src/core/ext/lb_policy/round_robin/round_robin.c b/src/core/ext/lb_policy/round_robin/round_robin.c
index da2cdfe8e9..40dd7c5940 100644
--- a/src/core/ext/lb_policy/round_robin/round_robin.c
+++ b/src/core/ext/lb_policy/round_robin/round_robin.c
@@ -333,7 +333,7 @@ static void start_picking(grpc_exec_ctx *exec_ctx, round_robin_lb_policy *p) {
   p->started_picking = 1;
 
   if (grpc_lb_round_robin_trace) {
-    gpr_log(GPR_DEBUG, "LB_POLICY: p=%p num_subchannels=%d", p,
+    gpr_log(GPR_DEBUG, "LB_POLICY: p=%p num_subchannels=%" PRIuPTR, p,
             p->num_subchannels);
   }
 
diff --git a/src/core/ext/resolver/dns/native/dns_resolver.c b/src/core/ext/resolver/dns/native/dns_resolver.c
index 620ba4e2aa..5efc95e0fa 100644
--- a/src/core/ext/resolver/dns/native/dns_resolver.c
+++ b/src/core/ext/resolver/dns/native/dns_resolver.c
@@ -183,7 +183,8 @@ static void dns_on_resolved(grpc_exec_ctx *exec_ctx, void *arg,
     gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
     gpr_timespec next_try = gpr_backoff_step(&r->backoff_state, now);
     gpr_timespec timeout = gpr_time_sub(next_try, now);
-    gpr_log(GPR_DEBUG, "dns resolution failed: retrying in %d.%09d seconds",
+    gpr_log(GPR_DEBUG,
+            "dns resolution failed: retrying in %" PRId64 ".%09d seconds",
             timeout.tv_sec, timeout.tv_nsec);
     GPR_ASSERT(!r->have_retry_timer);
     r->have_retry_timer = true;
diff --git a/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c b/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c
index 0428bb1e3d..c95dd20d1d 100644
--- a/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c
+++ b/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c
@@ -111,13 +111,14 @@ int grpc_server_add_insecure_http2_port(grpc_server *server, const char *addr) {
     }
   }
   if (count == 0) {
-    gpr_log(GPR_ERROR, "No address added out of total %d resolved",
+    gpr_log(GPR_ERROR, "No address added out of total %" PRIuPTR " resolved",
             resolved->naddrs);
     goto error;
   }
   if (count != resolved->naddrs) {
-    gpr_log(GPR_ERROR, "Only %d addresses added out of total %d resolved",
-            count, resolved->naddrs);
+    gpr_log(GPR_ERROR,
+            "Only %d addresses added out of total %" PRIuPTR " resolved", count,
+            resolved->naddrs);
   }
   grpc_resolved_addresses_destroy(resolved);
 
diff --git a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
index ebbefbcd89..e3437e5ed3 100644
--- a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
+++ b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
@@ -229,13 +229,14 @@ int grpc_server_add_secure_http2_port(grpc_server *server, const char *addr,
     }
   }
   if (count == 0) {
-    gpr_log(GPR_ERROR, "No address added out of total %d resolved",
+    gpr_log(GPR_ERROR, "No address added out of total %" PRIuPTR " resolved",
             resolved->naddrs);
     goto error;
   }
   if (count != resolved->naddrs) {
-    gpr_log(GPR_ERROR, "Only %d addresses added out of total %d resolved",
-            count, resolved->naddrs);
+    gpr_log(GPR_ERROR,
+            "Only %d addresses added out of total %" PRIuPTR " resolved", count,
+            resolved->naddrs);
     /* if it's an error, don't we want to goto error; here ? */
   }
   grpc_resolved_addresses_destroy(resolved);
diff --git a/src/core/ext/transport/chttp2/transport/chttp2_transport.c b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
index 2375a4587f..6e8640f1b3 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_transport.c
+++ b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
@@ -964,7 +964,7 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx,
     if (metadata_size > metadata_peer_limit) {
       gpr_log(GPR_DEBUG,
               "to-be-sent initial metadata size exceeds peer limit "
-              "(%lu vs. %lu)",
+              "(%" PRIuPTR " vs. %" PRIuPTR ")",
               metadata_size, metadata_peer_limit);
       cancel_from_api(exec_ctx, transport_global, stream_global,
                       GRPC_STATUS_RESOURCE_EXHAUSTED, NULL);
@@ -1019,7 +1019,7 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx,
     if (metadata_size > metadata_peer_limit) {
       gpr_log(GPR_DEBUG,
               "to-be-sent trailing metadata size exceeds peer limit "
-              "(%lu vs. %lu)",
+              "(%" PRIuPTR " vs. %" PRIuPTR ")",
               metadata_size, metadata_peer_limit);
       cancel_from_api(exec_ctx, transport_global, stream_global,
                       GRPC_STATUS_RESOURCE_EXHAUSTED, NULL);
@@ -2019,10 +2019,13 @@ static char *format_flowctl_context_var(const char *context, const char *var,
                                         int64_t val, uint32_t id,
                                         char **scope) {
   char *underscore_pos;
+  char *buf;
   char *result;
   if (context == NULL) {
     *scope = NULL;
-    gpr_asprintf(&result, "%s(%lld)", var, val);
+    gpr_asprintf(&buf, "%s(%" PRId64 ")", var, val);
+    result = gpr_leftpad(buf, ' ', 40);
+    gpr_free(buf);
     return result;
   }
   underscore_pos = strchr(context, '_');
@@ -2033,7 +2036,9 @@ static char *format_flowctl_context_var(const char *context, const char *var,
     gpr_asprintf(scope, "%s[%d]", tmp, id);
     gpr_free(tmp);
   }
-  gpr_asprintf(&result, "%s.%s(%lld)", underscore_pos + 1, var, val);
+  gpr_asprintf(&buf, "%s.%s(%" PRId64 ")", underscore_pos + 1, var, val);
+  result = gpr_leftpad(buf, ' ', 40);
+  gpr_free(buf);
   return result;
 }
 
@@ -2054,6 +2059,8 @@ void grpc_chttp2_flowctl_trace(const char *file, int line, const char *phase,
                                uint32_t stream_id, int64_t val1, int64_t val2) {
   char *scope1;
   char *scope2;
+  char *tmp_phase;
+  char *tmp_scope1;
   char *label1 =
       format_flowctl_context_var(context1, var1, val1, stream_id, &scope1);
   char *label2 =
@@ -2061,14 +2068,18 @@ void grpc_chttp2_flowctl_trace(const char *file, int line, const char *phase,
   char *clisvr = is_client ? "client" : "server";
   char *prefix;
 
-  gpr_asprintf(&prefix, "FLOW % 8s: %s % 11s ", phase, clisvr, scope1);
+  tmp_phase = gpr_leftpad(phase, ' ', 8);
+  tmp_scope1 = gpr_leftpad(scope1, ' ', 11);
+  gpr_asprintf(&prefix, "FLOW %s: %s %s ", phase, clisvr, scope1);
+  gpr_free(tmp_phase);
+  gpr_free(tmp_scope1);
 
   switch (op) {
     case GRPC_CHTTP2_FLOWCTL_MOVE:
       GPR_ASSERT(samestr(scope1, scope2));
       if (val2 != 0) {
         gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-                "%sMOVE   % 40s <- % 40s giving %d", prefix, label1, label2,
+                "%sMOVE   %s <- %s giving %" PRId64, prefix, label1, label2,
                 val1 + val2);
       }
       break;
@@ -2076,7 +2087,7 @@ void grpc_chttp2_flowctl_trace(const char *file, int line, const char *phase,
       GPR_ASSERT(val2 >= 0);
       if (val2 != 0) {
         gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-                "%sCREDIT % 40s by % 40s giving %d", prefix, label1, label2,
+                "%sCREDIT %s by %s giving %" PRId64, prefix, label1, label2,
                 val1 + val2);
       }
       break;
@@ -2084,7 +2095,7 @@ void grpc_chttp2_flowctl_trace(const char *file, int line, const char *phase,
       GPR_ASSERT(val2 >= 0);
       if (val2 != 0) {
         gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-                "%sDEBIT  % 40s by % 40s giving %d", prefix, label1, label2,
+                "%sDEBIT  %s by %s giving %" PRId64, prefix, label1, label2,
                 val1 - val2);
       }
       break;
diff --git a/src/core/ext/transport/chttp2/transport/parsing.c b/src/core/ext/transport/chttp2/transport/parsing.c
index 4bd374b7fa..3c74258352 100644
--- a/src/core/ext/transport/chttp2/transport/parsing.c
+++ b/src/core/ext/transport/chttp2/transport/parsing.c
@@ -534,14 +534,14 @@ static grpc_chttp2_parse_error update_incoming_window(
     grpc_chttp2_stream_parsing *stream_parsing) {
   uint32_t incoming_frame_size = transport_parsing->incoming_frame_size;
   if (incoming_frame_size > transport_parsing->incoming_window) {
-    gpr_log(GPR_ERROR, "frame of size %d overflows incoming window of %d",
+    gpr_log(GPR_ERROR, "frame of size %d overflows incoming window of %" PRId64,
             transport_parsing->incoming_frame_size,
             transport_parsing->incoming_window);
     return GRPC_CHTTP2_CONNECTION_ERROR;
   }
 
   if (incoming_frame_size > stream_parsing->incoming_window) {
-    gpr_log(GPR_ERROR, "frame of size %d overflows incoming window of %d",
+    gpr_log(GPR_ERROR, "frame of size %d overflows incoming window of %" PRId64,
             transport_parsing->incoming_frame_size,
             stream_parsing->incoming_window);
     return GRPC_CHTTP2_CONNECTION_ERROR;
@@ -649,7 +649,8 @@ static void on_initial_header(void *tp, grpc_mdelem *md) {
     if (new_size > metadata_size_limit) {
       if (!stream_parsing->exceeded_metadata_size) {
         gpr_log(GPR_DEBUG,
-                "received initial metadata size exceeds limit (%lu vs. %lu)",
+                "received initial metadata size exceeds limit (%" PRIuPTR
+                " vs. %" PRIuPTR ")",
                 new_size, metadata_size_limit);
         stream_parsing->seen_error = true;
         stream_parsing->exceeded_metadata_size = true;
@@ -695,7 +696,8 @@ static void on_trailing_header(void *tp, grpc_mdelem *md) {
   if (new_size > metadata_size_limit) {
     if (!stream_parsing->exceeded_metadata_size) {
       gpr_log(GPR_DEBUG,
-              "received trailing metadata size exceeds limit (%lu vs. %lu)",
+              "received trailing metadata size exceeds limit (%" PRIuPTR
+              " vs. %" PRIuPTR ")",
               new_size, metadata_size_limit);
       stream_parsing->seen_error = true;
       stream_parsing->exceeded_metadata_size = true;
diff --git a/src/core/lib/channel/compress_filter.c b/src/core/lib/channel/compress_filter.c
index 4fe9a7f045..32f4f8d37e 100644
--- a/src/core/lib/channel/compress_filter.c
+++ b/src/core/lib/channel/compress_filter.c
@@ -177,8 +177,8 @@ static void finish_send_message(grpc_exec_ctx *exec_ctx,
       const float savings_ratio = 1.0f - (float)after_size / (float)before_size;
       GPR_ASSERT(grpc_compression_algorithm_name(calld->compression_algorithm,
                                                  &algo_name));
-      gpr_log(GPR_DEBUG,
-              "Compressed[%s] %d bytes vs. %d bytes (%.2f%% savings)",
+      gpr_log(GPR_DEBUG, "Compressed[%s] %" PRIuPTR " bytes vs. %" PRIuPTR
+                         " bytes (%.2f%% savings)",
               algo_name, before_size, after_size, 100 * savings_ratio);
     }
     gpr_slice_buffer_swap(&calld->slices, &tmp);
@@ -188,10 +188,10 @@ static void finish_send_message(grpc_exec_ctx *exec_ctx,
       char *algo_name;
       GPR_ASSERT(grpc_compression_algorithm_name(calld->compression_algorithm,
                                                  &algo_name));
-      gpr_log(
-          GPR_DEBUG,
-          "Algorithm '%s' enabled but decided not to compress. Input size: %d",
-          algo_name, calld->slices.length);
+      gpr_log(GPR_DEBUG,
+              "Algorithm '%s' enabled but decided not to compress. Input size: "
+              "%" PRIuPTR,
+              algo_name, calld->slices.length);
     }
   }
 
diff --git a/src/core/lib/iomgr/iomgr.c b/src/core/lib/iomgr/iomgr.c
index 60cef8ba77..89292a153e 100644
--- a/src/core/lib/iomgr/iomgr.c
+++ b/src/core/lib/iomgr/iomgr.c
@@ -96,7 +96,8 @@ void grpc_iomgr_shutdown(void) {
             gpr_time_sub(gpr_now(GPR_CLOCK_REALTIME), last_warning_time),
             gpr_time_from_seconds(1, GPR_TIMESPAN)) >= 0) {
       if (g_root_object.next != &g_root_object) {
-        gpr_log(GPR_DEBUG, "Waiting for %d iomgr objects to be destroyed",
+        gpr_log(GPR_DEBUG,
+                "Waiting for %" PRIuPTR " iomgr objects to be destroyed",
                 count_objects());
       }
       last_warning_time = gpr_now(GPR_CLOCK_REALTIME);
@@ -114,9 +115,9 @@ void grpc_iomgr_shutdown(void) {
       if (gpr_cv_wait(&g_rcv, &g_mu, short_deadline)) {
         if (gpr_time_cmp(gpr_now(GPR_CLOCK_REALTIME), shutdown_deadline) > 0) {
           if (g_root_object.next != &g_root_object) {
-            gpr_log(GPR_DEBUG,
-                    "Failed to free %d iomgr objects before shutdown deadline: "
-                    "memory leaks are likely",
+            gpr_log(GPR_DEBUG, "Failed to free %" PRIuPTR
+                               " iomgr objects before shutdown deadline: "
+                               "memory leaks are likely",
                     count_objects());
             dump_objects("LEAKED");
             if (grpc_iomgr_abort_on_leaks()) {
diff --git a/src/core/lib/support/log_linux.c b/src/core/lib/support/log_linux.c
index ca04c022e3..508fae4eec 100644
--- a/src/core/lib/support/log_linux.c
+++ b/src/core/lib/support/log_linux.c
@@ -95,9 +95,9 @@ void gpr_default_log(gpr_log_func_args *args) {
     strcpy(time_buffer, "error:strftime");
   }
 
-  gpr_asprintf(&prefix, "%s%s.%09d %7tu %s:%d]",
+  gpr_asprintf(&prefix, "%s%s.%09" PRId32 " %7ld %s:%d]",
                gpr_log_severity_string(args->severity), time_buffer,
-               (int)(now.tv_nsec), gettid(), display_file, args->line);
+               now.tv_nsec, gettid(), display_file, args->line);
 
   fprintf(stderr, "%-60s %s\n", prefix, args->message);
   gpr_free(prefix);
diff --git a/src/core/lib/support/string.c b/src/core/lib/support/string.c
index a2ab6c5f1f..30c1e67647 100644
--- a/src/core/lib/support/string.c
+++ b/src/core/lib/support/string.c
@@ -194,6 +194,16 @@ int int64_ttoa(int64_t value, char *string) {
   return i;
 }
 
+char *gpr_leftpad(const char *str, char flag, size_t length) {
+  const size_t str_length = strlen(str);
+  const size_t out_length = str_length > length ? str_length : length;
+  char *out = gpr_malloc(out_length + 1);
+  memset(out, flag, out_length - str_length);
+  memcpy(out + out_length - str_length, str, str_length);
+  out[out_length] = 0;
+  return out;
+}
+
 char *gpr_strjoin(const char **strs, size_t nstrs, size_t *final_length) {
   return gpr_strjoin_sep(strs, nstrs, "", final_length);
 }
diff --git a/src/core/lib/support/string.h b/src/core/lib/support/string.h
index ea58610914..2b6bb3eec6 100644
--- a/src/core/lib/support/string.h
+++ b/src/core/lib/support/string.h
@@ -83,6 +83,10 @@ int int64_ttoa(int64_t value, char *output);
 /* Reverse a run of bytes */
 void gpr_reverse_bytes(char *str, int len);
 
+/* Pad a string with flag characters. The given length specifies the minimum
+   field width. The input string is never truncated. */
+char *gpr_leftpad(const char *str, char flag, size_t length);
+
 /* Join a set of strings, returning the resulting string.
    Total combined length (excluding null terminator) is returned in total_length
    if it is non-null. */
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index a9b1e25a77..c613f325dc 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -1182,7 +1182,7 @@ static void validate_filtered_metadata(grpc_exec_ctx *exec_ctx,
     if (algo >= GRPC_COMPRESS_ALGORITHMS_COUNT) {
       gpr_asprintf(&error_msg, "Invalid compression algorithm value '%d'.",
                    algo);
-      gpr_log(GPR_ERROR, error_msg);
+      gpr_log(GPR_ERROR, "%s", error_msg);
       close_with_status(exec_ctx, call, GRPC_STATUS_UNIMPLEMENTED, error_msg);
     } else if (grpc_compression_options_is_algorithm_enabled(
                    &compression_options, algo) == 0) {
@@ -1191,7 +1191,7 @@ static void validate_filtered_metadata(grpc_exec_ctx *exec_ctx,
       grpc_compression_algorithm_name(algo, &algo_name);
       gpr_asprintf(&error_msg, "Compression algorithm '%s' is disabled.",
                    algo_name);
-      gpr_log(GPR_ERROR, error_msg);
+      gpr_log(GPR_ERROR, "%s", error_msg);
       close_with_status(exec_ctx, call, GRPC_STATUS_UNIMPLEMENTED, error_msg);
     } else {
       call->incoming_compression_algorithm = algo;
diff --git a/src/core/lib/surface/call_log_batch.c b/src/core/lib/surface/call_log_batch.c
index a6d1d5149f..31c074f15d 100644
--- a/src/core/lib/surface/call_log_batch.c
+++ b/src/core/lib/surface/call_log_batch.c
@@ -112,7 +112,7 @@ void grpc_call_log_batch(char *file, int line, gpr_log_severity severity,
   size_t i;
   for (i = 0; i < nops; i++) {
     tmp = grpc_op_string(&ops[i]);
-    gpr_log(file, line, severity, "ops[%d]: %s", i, tmp);
+    gpr_log(file, line, severity, "ops[%" PRIuPTR "]: %s", i, tmp);
     gpr_free(tmp);
   }
 }
diff --git a/src/core/lib/transport/metadata.c b/src/core/lib/transport/metadata.c
index 79de54beb5..0677f29766 100644
--- a/src/core/lib/transport/metadata.c
+++ b/src/core/lib/transport/metadata.c
@@ -235,7 +235,7 @@ void grpc_mdctx_global_shutdown(void) {
     gc_mdtab(shard);
     /* TODO(ctiller): GPR_ASSERT(shard->count == 0); */
     if (shard->count != 0) {
-      gpr_log(GPR_DEBUG, "WARNING: %d metadata elements were leaked",
+      gpr_log(GPR_DEBUG, "WARNING: %" PRIuPTR " metadata elements were leaked",
               shard->count);
       if (grpc_iomgr_abort_on_leaks()) {
         abort();
@@ -248,7 +248,7 @@ void grpc_mdctx_global_shutdown(void) {
     gpr_mu_destroy(&shard->mu);
     /* TODO(ctiller): GPR_ASSERT(shard->count == 0); */
     if (shard->count != 0) {
-      gpr_log(GPR_DEBUG, "WARNING: %d metadata strings were leaked",
+      gpr_log(GPR_DEBUG, "WARNING: %" PRIuPTR " metadata strings were leaked",
               shard->count);
       for (size_t j = 0; j < shard->capacity; j++) {
         for (internal_string *s = shard->strs[j]; s; s = s->bucket_next) {
diff --git a/src/python/grpcio/grpc/_cython/imports.generated.h b/src/python/grpcio/grpc/_cython/imports.generated.h
index 16bb5cdfab..62865f8a0e 100644
--- a/src/python/grpcio/grpc/_cython/imports.generated.h
+++ b/src/python/grpcio/grpc/_cython/imports.generated.h
@@ -482,7 +482,7 @@ extern grpc_byte_buffer_reader_readall_type grpc_byte_buffer_reader_readall_impo
 typedef grpc_byte_buffer *(*grpc_raw_byte_buffer_from_reader_type)(grpc_byte_buffer_reader *reader);
 extern grpc_raw_byte_buffer_from_reader_type grpc_raw_byte_buffer_from_reader_import;
 #define grpc_raw_byte_buffer_from_reader grpc_raw_byte_buffer_from_reader_import
-typedef void(*gpr_log_type)(const char *file, int line, gpr_log_severity severity, const char *format, ...);
+typedef void(*gpr_log_type)(const char *file, int line, gpr_log_severity severity, const char *format, ...) GPRC_PRINT_FORMAT_CHECK(4, 5);
 extern gpr_log_type gpr_log_import;
 #define gpr_log gpr_log_import
 typedef void(*gpr_log_message_type)(const char *file, int line, gpr_log_severity severity, const char *message);
@@ -821,7 +821,7 @@ extern gpr_format_message_type gpr_format_message_import;
 typedef char *(*gpr_strdup_type)(const char *src);
 extern gpr_strdup_type gpr_strdup_import;
 #define gpr_strdup gpr_strdup_import
-typedef int(*gpr_asprintf_type)(char **strp, const char *format, ...);
+typedef int(*gpr_asprintf_type)(char **strp, const char *format, ...) GPRC_PRINT_FORMAT_CHECK(2, 3);
 extern gpr_asprintf_type gpr_asprintf_import;
 #define gpr_asprintf gpr_asprintf_import
 typedef const char *(*gpr_subprocess_binary_extension_type)();
diff --git a/src/ruby/ext/grpc/rb_grpc_imports.generated.h b/src/ruby/ext/grpc/rb_grpc_imports.generated.h
index 9c86a3690c..e9845cd7e2 100644
--- a/src/ruby/ext/grpc/rb_grpc_imports.generated.h
+++ b/src/ruby/ext/grpc/rb_grpc_imports.generated.h
@@ -482,7 +482,7 @@ extern grpc_byte_buffer_reader_readall_type grpc_byte_buffer_reader_readall_impo
 typedef grpc_byte_buffer *(*grpc_raw_byte_buffer_from_reader_type)(grpc_byte_buffer_reader *reader);
 extern grpc_raw_byte_buffer_from_reader_type grpc_raw_byte_buffer_from_reader_import;
 #define grpc_raw_byte_buffer_from_reader grpc_raw_byte_buffer_from_reader_import
-typedef void(*gpr_log_type)(const char *file, int line, gpr_log_severity severity, const char *format, ...);
+typedef void(*gpr_log_type)(const char *file, int line, gpr_log_severity severity, const char *format, ...) GPRC_PRINT_FORMAT_CHECK(4, 5);
 extern gpr_log_type gpr_log_import;
 #define gpr_log gpr_log_import
 typedef void(*gpr_log_message_type)(const char *file, int line, gpr_log_severity severity, const char *message);
@@ -821,7 +821,7 @@ extern gpr_format_message_type gpr_format_message_import;
 typedef char *(*gpr_strdup_type)(const char *src);
 extern gpr_strdup_type gpr_strdup_import;
 #define gpr_strdup gpr_strdup_import
-typedef int(*gpr_asprintf_type)(char **strp, const char *format, ...);
+typedef int(*gpr_asprintf_type)(char **strp, const char *format, ...) GPRC_PRINT_FORMAT_CHECK(2, 3);
 extern gpr_asprintf_type gpr_asprintf_import;
 #define gpr_asprintf gpr_asprintf_import
 typedef const char *(*gpr_subprocess_binary_extension_type)();
diff --git a/test/core/client_config/lb_policies_test.c b/test/core/client_config/lb_policies_test.c
index 1534360dea..3160312db6 100644
--- a/test/core/client_config/lb_policies_test.c
+++ b/test/core/client_config/lb_policies_test.c
@@ -135,7 +135,7 @@ static void drain_cq(grpc_completion_queue *cq) {
 }
 
 static void kill_server(const servers_fixture *f, size_t i) {
-  gpr_log(GPR_INFO, "KILLING SERVER %d", i);
+  gpr_log(GPR_INFO, "KILLING SERVER %" PRIuPTR, i);
   GPR_ASSERT(f->servers[i] != NULL);
   grpc_server_shutdown_and_notify(f->servers[i], f->cq, tag(10000));
   GPR_ASSERT(
@@ -157,7 +157,7 @@ typedef struct request_data {
 static void revive_server(const servers_fixture *f, request_data *rdata,
                           size_t i) {
   int got_port;
-  gpr_log(GPR_INFO, "RAISE AGAIN SERVER %d", i);
+  gpr_log(GPR_INFO, "RAISE AGAIN SERVER %" PRIuPTR, i);
   GPR_ASSERT(f->servers[i] == NULL);
 
   gpr_log(GPR_DEBUG, "revive: %s", f->servers_hostports[i]);
@@ -311,7 +311,7 @@ static int *perform_request(servers_fixture *f, grpc_channel *client,
             .type != GRPC_QUEUE_TIMEOUT) {
       GPR_ASSERT(ev.type == GRPC_OP_COMPLETE);
       read_tag = ((int)(intptr_t)ev.tag);
-      gpr_log(GPR_DEBUG, "EVENT: success:%d, type:%d, tag:%d iter:%d",
+      gpr_log(GPR_DEBUG, "EVENT: success:%d, type:%d, tag:%d iter:%" PRIuPTR,
               ev.success, ev.type, read_tag, iter_num);
       if (ev.success && read_tag >= 1000) {
         GPR_ASSERT(s_idx == -1); /* only one server must reply */
@@ -643,7 +643,8 @@ static void print_failed_expectations(const int *expected_connection_sequence,
                                       const size_t num_iters) {
   size_t i;
   for (i = 0; i < num_iters; i++) {
-    gpr_log(GPR_ERROR, "FAILURE: Iter (expected, actual): %d (%d, %d)", i,
+    gpr_log(GPR_ERROR,
+            "FAILURE: Iter (expected, actual): %" PRIuPTR " (%d, %d)", i,
             expected_connection_sequence[i % expected_seq_length],
             actual_connection_sequence[i]);
   }
@@ -726,8 +727,8 @@ static void verify_total_carnage_round_robin(
     const int actual = actual_connection_sequence[i];
     const int expected = -1;
     if (actual != expected) {
-      gpr_log(GPR_ERROR, "FAILURE: expected %d, actual %d at iter %d", expected,
-              actual, i);
+      gpr_log(GPR_ERROR, "FAILURE: expected %d, actual %d at iter %" PRIuPTR,
+              expected, actual, i);
       abort();
     }
   }
diff --git a/test/core/client_config/set_initial_connect_string_test.c b/test/core/client_config/set_initial_connect_string_test.c
index 438b949236..63371a6b34 100644
--- a/test/core/client_config/set_initial_connect_string_test.c
+++ b/test/core/client_config/set_initial_connect_string_test.c
@@ -69,7 +69,7 @@ static void handle_read(grpc_exec_ctx *exec_ctx, void *arg, bool success) {
   GPR_ASSERT(success);
   gpr_slice_buffer_move_into(&state.temp_incoming_buffer,
                              &state.incoming_buffer);
-  gpr_log(GPR_DEBUG, "got %d bytes, magic is %d bytes",
+  gpr_log(GPR_DEBUG, "got %" PRIuPTR " bytes, magic is %" PRIuPTR " bytes",
           state.incoming_buffer.length, strlen(magic_connect_string));
   if (state.incoming_buffer.length > strlen(magic_connect_string)) {
     gpr_atm_rel_store(&state.done_atm, 1);
@@ -173,8 +173,8 @@ static void actually_poll_server(void *arg) {
     bool done = gpr_atm_acq_load(&state.done_atm) != 0;
     gpr_timespec time_left =
         gpr_time_sub(deadline, gpr_now(GPR_CLOCK_REALTIME));
-    gpr_log(GPR_DEBUG, "done=%d, time_left=%d.%09d", done, time_left.tv_sec,
-            time_left.tv_nsec);
+    gpr_log(GPR_DEBUG, "done=%d, time_left=%" PRId64 ".%09" PRId32, done,
+            time_left.tv_sec, time_left.tv_nsec);
     if (done || gpr_time_cmp(time_left, gpr_time_0(GPR_TIMESPAN)) < 0) {
       break;
     }
diff --git a/test/core/compression/message_compress_test.c b/test/core/compression/message_compress_test.c
index 1a93903346..47ecf72e08 100644
--- a/test/core/compression/message_compress_test.c
+++ b/test/core/compression/message_compress_test.c
@@ -66,13 +66,14 @@ static void assert_passthrough(gpr_slice value,
   char *algorithm_name;
 
   GPR_ASSERT(grpc_compression_algorithm_name(algorithm, &algorithm_name) != 0);
-  gpr_log(GPR_INFO,
-          "assert_passthrough: value_length=%d value_hash=0x%08x "
-          "algorithm='%s' uncompressed_split='%s' compressed_split='%s'",
-          GPR_SLICE_LENGTH(value), gpr_murmur_hash3(GPR_SLICE_START_PTR(value),
-                                                    GPR_SLICE_LENGTH(value), 0),
-          algorithm_name, grpc_slice_split_mode_name(uncompressed_split_mode),
-          grpc_slice_split_mode_name(compressed_split_mode));
+  gpr_log(
+      GPR_INFO, "assert_passthrough: value_length=%" PRIuPTR
+                " value_hash=0x%08x "
+                "algorithm='%s' uncompressed_split='%s' compressed_split='%s'",
+      GPR_SLICE_LENGTH(value),
+      gpr_murmur_hash3(GPR_SLICE_START_PTR(value), GPR_SLICE_LENGTH(value), 0),
+      algorithm_name, grpc_slice_split_mode_name(uncompressed_split_mode),
+      grpc_slice_split_mode_name(compressed_split_mode));
 
   gpr_slice_buffer_init(&input);
   gpr_slice_buffer_init(&compressed_raw);
diff --git a/test/core/end2end/tests/cancel_with_status.c b/test/core/end2end/tests/cancel_with_status.c
index 83629a9a02..673c7051ad 100644
--- a/test/core/end2end/tests/cancel_with_status.c
+++ b/test/core/end2end/tests/cancel_with_status.c
@@ -112,7 +112,7 @@ static void simple_request_body(grpc_end2end_test_fixture f, size_t num_ops) {
   char *details = NULL;
   size_t details_capacity = 0;
 
-  gpr_log(GPR_DEBUG, "test with %d ops", num_ops);
+  gpr_log(GPR_DEBUG, "test with %" PRIuPTR " ops", num_ops);
 
   c = grpc_channel_create_call(f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
                                "/foo", "foo.test.google.fr:1234", deadline,
diff --git a/test/core/end2end/tests/negative_deadline.c b/test/core/end2end/tests/negative_deadline.c
index fd56c8b4ff..dff7992f63 100644
--- a/test/core/end2end/tests/negative_deadline.c
+++ b/test/core/end2end/tests/negative_deadline.c
@@ -112,7 +112,7 @@ static void simple_request_body(grpc_end2end_test_fixture f, size_t num_ops) {
   char *details = NULL;
   size_t details_capacity = 0;
 
-  gpr_log(GPR_DEBUG, "test with %d ops", num_ops);
+  gpr_log(GPR_DEBUG, "test with %" PRIuPTR " ops", num_ops);
 
   c = grpc_channel_create_call(f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
                                "/foo", "foo.test.google.fr:1234", deadline,
diff --git a/test/core/iomgr/endpoint_tests.c b/test/core/iomgr/endpoint_tests.c
index 52082c3c6b..6d15ecf141 100644
--- a/test/core/iomgr/endpoint_tests.c
+++ b/test/core/iomgr/endpoint_tests.c
@@ -188,13 +188,15 @@ static void read_and_write_test(grpc_endpoint_test_config config,
   grpc_endpoint_test_fixture f =
       begin_test(config, "read_and_write_test", slice_size);
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  gpr_log(GPR_DEBUG, "num_bytes=%d write_size=%d slice_size=%d shutdown=%d",
+  gpr_log(GPR_DEBUG, "num_bytes=%" PRIuPTR " write_size=%" PRIuPTR
+                     " slice_size=%" PRIuPTR " shutdown=%d",
           num_bytes, write_size, slice_size, shutdown);
 
   if (shutdown) {
     gpr_log(GPR_INFO, "Start read and write shutdown test");
   } else {
-    gpr_log(GPR_INFO, "Start read and write test with %d bytes, slice size %d",
+    gpr_log(GPR_INFO, "Start read and write test with %" PRIuPTR
+                      " bytes, slice size %" PRIuPTR,
             num_bytes, slice_size);
   }
 
diff --git a/test/core/iomgr/fd_posix_test.c b/test/core/iomgr/fd_posix_test.c
index 0630f1d10e..24ba474680 100644
--- a/test/core/iomgr/fd_posix_test.c
+++ b/test/core/iomgr/fd_posix_test.c
@@ -398,7 +398,7 @@ static void test_grpc_fd(void) {
   client_wait_and_shutdown(&cl);
   server_wait_and_shutdown(&sv);
   GPR_ASSERT(sv.read_bytes_total == cl.write_bytes_total);
-  gpr_log(GPR_INFO, "Total read bytes %d", sv.read_bytes_total);
+  gpr_log(GPR_INFO, "Total read bytes %" PRIdPTR, sv.read_bytes_total);
 }
 
 typedef struct fd_change_data {
diff --git a/test/core/iomgr/tcp_posix_test.c b/test/core/iomgr/tcp_posix_test.c
index 7a98fa0e50..19ba258303 100644
--- a/test/core/iomgr/tcp_posix_test.c
+++ b/test/core/iomgr/tcp_posix_test.c
@@ -151,7 +151,7 @@ static void read_cb(grpc_exec_ctx *exec_ctx, void *user_data, bool success) {
   read_bytes = count_slices(state->incoming.slices, state->incoming.count,
                             &current_data);
   state->read_bytes += read_bytes;
-  gpr_log(GPR_INFO, "Read %d bytes of %d", read_bytes,
+  gpr_log(GPR_INFO, "Read %" PRIuPTR " bytes of %" PRIuPTR, read_bytes,
           state->target_read_bytes);
   if (state->read_bytes >= state->target_read_bytes) {
     gpr_mu_unlock(g_mu);
@@ -170,8 +170,8 @@ static void read_test(size_t num_bytes, size_t slice_size) {
   gpr_timespec deadline = GRPC_TIMEOUT_SECONDS_TO_DEADLINE(20);
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
-  gpr_log(GPR_INFO, "Read test of size %d, slice size %d", num_bytes,
-          slice_size);
+  gpr_log(GPR_INFO, "Read test of size %" PRIuPTR ", slice size %" PRIuPTR,
+          num_bytes, slice_size);
 
   create_sockets(sv);
 
@@ -179,7 +179,7 @@ static void read_test(size_t num_bytes, size_t slice_size) {
   grpc_endpoint_add_to_pollset(&exec_ctx, ep, g_pollset);
 
   written_bytes = fill_socket_partial(sv[0], num_bytes);
-  gpr_log(GPR_INFO, "Wrote %d bytes", written_bytes);
+  gpr_log(GPR_INFO, "Wrote %" PRIuPTR " bytes", written_bytes);
 
   state.ep = ep;
   state.read_bytes = 0;
@@ -216,7 +216,7 @@ static void large_read_test(size_t slice_size) {
   gpr_timespec deadline = GRPC_TIMEOUT_SECONDS_TO_DEADLINE(20);
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
-  gpr_log(GPR_INFO, "Start large read test, slice size %d", slice_size);
+  gpr_log(GPR_INFO, "Start large read test, slice size %" PRIuPTR, slice_size);
 
   create_sockets(sv);
 
@@ -225,7 +225,7 @@ static void large_read_test(size_t slice_size) {
   grpc_endpoint_add_to_pollset(&exec_ctx, ep, g_pollset);
 
   written_bytes = fill_socket(sv[0]);
-  gpr_log(GPR_INFO, "Wrote %d bytes", written_bytes);
+  gpr_log(GPR_INFO, "Wrote %" PRIuPTR " bytes", written_bytes);
 
   state.ep = ep;
   state.read_bytes = 0;
@@ -344,8 +344,9 @@ static void write_test(size_t num_bytes, size_t slice_size) {
   gpr_timespec deadline = GRPC_TIMEOUT_SECONDS_TO_DEADLINE(20);
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
-  gpr_log(GPR_INFO, "Start write test with %d bytes, slice size %d", num_bytes,
-          slice_size);
+  gpr_log(GPR_INFO,
+          "Start write test with %" PRIuPTR " bytes, slice size %" PRIuPTR,
+          num_bytes, slice_size);
 
   create_sockets(sv);
 
@@ -404,8 +405,9 @@ static void release_fd_test(size_t num_bytes, size_t slice_size) {
   int fd_released_done = 0;
   grpc_closure_init(&fd_released_cb, &on_fd_released, &fd_released_done);
 
-  gpr_log(GPR_INFO, "Release fd read_test of size %d, slice size %d", num_bytes,
-          slice_size);
+  gpr_log(GPR_INFO,
+          "Release fd read_test of size %" PRIuPTR ", slice size %" PRIuPTR,
+          num_bytes, slice_size);
 
   create_sockets(sv);
 
@@ -414,7 +416,7 @@ static void release_fd_test(size_t num_bytes, size_t slice_size) {
   grpc_endpoint_add_to_pollset(&exec_ctx, ep, g_pollset);
 
   written_bytes = fill_socket_partial(sv[0], num_bytes);
-  gpr_log(GPR_INFO, "Wrote %d bytes", written_bytes);
+  gpr_log(GPR_INFO, "Wrote %" PRIuPTR " bytes", written_bytes);
 
   state.ep = ep;
   state.read_bytes = 0;
diff --git a/test/core/support/slice_test.c b/test/core/support/slice_test.c
index 2df38376a9..0da483a321 100644
--- a/test/core/support/slice_test.c
+++ b/test/core/support/slice_test.c
@@ -164,7 +164,7 @@ static void test_slice_split_head_works(size_t length) {
   size_t i;
 
   LOG_TEST_NAME("test_slice_split_head_works");
-  gpr_log(GPR_INFO, "length=%d", length);
+  gpr_log(GPR_INFO, "length=%" PRIuPTR, length);
 
   /* Create a slice in which each byte is equal to the distance from it to the
      beginning of the slice. */
@@ -192,7 +192,7 @@ static void test_slice_split_tail_works(size_t length) {
   size_t i;
 
   LOG_TEST_NAME("test_slice_split_tail_works");
-  gpr_log(GPR_INFO, "length=%d", length);
+  gpr_log(GPR_INFO, "length=%" PRIuPTR, length);
 
   /* Create a slice in which each byte is equal to the distance from it to the
      beginning of the slice. */
diff --git a/test/core/support/string_test.c b/test/core/support/string_test.c
index d5f8107f21..553a824b3f 100644
--- a/test/core/support/string_test.c
+++ b/test/core/support/string_test.c
@@ -156,7 +156,7 @@ static void test_asprintf(void) {
   LOG_TEST_NAME("test_asprintf");
 
   /* Print an empty string. */
-  GPR_ASSERT(gpr_asprintf(&buf, "") == 0);
+  GPR_ASSERT(gpr_asprintf(&buf, "%s", "") == 0);
   GPR_ASSERT(buf[0] == '\0');
   gpr_free(buf);
 
@@ -334,6 +334,38 @@ static void test_int64toa() {
   GPR_ASSERT(0 == strcmp("-9223372036854775808", buf));
 }
 
+static void test_leftpad() {
+  char *padded;
+
+  padded = gpr_leftpad("foo", ' ', 5);
+  GPR_ASSERT(0 == strcmp("  foo", padded));
+  gpr_free(padded);
+
+  padded = gpr_leftpad("foo", ' ', 4);
+  GPR_ASSERT(0 == strcmp(" foo", padded));
+  gpr_free(padded);
+
+  padded = gpr_leftpad("foo", ' ', 3);
+  GPR_ASSERT(0 == strcmp("foo", padded));
+  gpr_free(padded);
+
+  padded = gpr_leftpad("foo", ' ', 2);
+  GPR_ASSERT(0 == strcmp("foo", padded));
+  gpr_free(padded);
+
+  padded = gpr_leftpad("foo", ' ', 1);
+  GPR_ASSERT(0 == strcmp("foo", padded));
+  gpr_free(padded);
+
+  padded = gpr_leftpad("foo", ' ', 0);
+  GPR_ASSERT(0 == strcmp("foo", padded));
+  gpr_free(padded);
+
+  padded = gpr_leftpad("foo", '0', 5);
+  GPR_ASSERT(0 == strcmp("00foo", padded));
+  gpr_free(padded);
+}
+
 int main(int argc, char **argv) {
   grpc_test_init(argc, argv);
   test_strdup();
@@ -346,5 +378,6 @@ int main(int argc, char **argv) {
   test_strsplit();
   test_ltoa();
   test_int64toa();
+  test_leftpad();
   return 0;
 }
diff --git a/test/core/surface/completion_queue_test.c b/test/core/surface/completion_queue_test.c
index 49a1fc441f..2fcd7f5a93 100644
--- a/test/core/surface/completion_queue_test.c
+++ b/test/core/surface/completion_queue_test.c
@@ -348,8 +348,8 @@ static void test_threading(size_t producers, size_t consumers) {
   size_t total_consumed = 0;
   static int optid = 101;
 
-  gpr_log(GPR_INFO, "%s: %d producers, %d consumers", "test_threading",
-          producers, consumers);
+  gpr_log(GPR_INFO, "%s: %" PRIuPTR " producers, %" PRIuPTR " consumers",
+          "test_threading", producers, consumers);
 
   /* start all threads: they will wait for phase1 */
   for (i = 0; i < producers + consumers; i++) {
diff --git a/test/core/transport/chttp2/bin_encoder_test.c b/test/core/transport/chttp2/bin_encoder_test.c
index 095861e974..08d10735a5 100644
--- a/test/core/transport/chttp2/bin_encoder_test.c
+++ b/test/core/transport/chttp2/bin_encoder_test.c
@@ -88,7 +88,8 @@ static void expect_combined_equiv(const char *s, size_t len, int line) {
     char *t = gpr_dump_slice(input, GPR_DUMP_HEX | GPR_DUMP_ASCII);
     char *e = gpr_dump_slice(expect, GPR_DUMP_HEX | GPR_DUMP_ASCII);
     char *g = gpr_dump_slice(got, GPR_DUMP_HEX | GPR_DUMP_ASCII);
-    gpr_log(GPR_ERROR, "FAILED:%d:\ntest: %s\ngot:  %s\nwant: %s", t, g, e);
+    gpr_log(GPR_ERROR, "FAILED:%d:\ntest: %s\ngot:  %s\nwant: %s", line, t, g,
+            e);
     gpr_free(t);
     gpr_free(e);
     gpr_free(g);
diff --git a/test/core/transport/metadata_test.c b/test/core/transport/metadata_test.c
index a4e9694a93..007892930c 100644
--- a/test/core/transport/metadata_test.c
+++ b/test/core/transport/metadata_test.c
@@ -166,7 +166,7 @@ static void test_things_stick_around(void) {
   grpc_init();
 
   for (i = 0; i < nstrs; i++) {
-    gpr_asprintf(&buffer, "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx%dx", i);
+    gpr_asprintf(&buffer, "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx%" PRIuPTR "x", i);
     strs[i] = grpc_mdstr_from_string(buffer);
     shuf[i] = i;
     gpr_free(buffer);
@@ -188,7 +188,8 @@ static void test_things_stick_around(void) {
   for (i = 0; i < nstrs; i++) {
     GRPC_MDSTR_UNREF(strs[shuf[i]]);
     for (j = i + 1; j < nstrs; j++) {
-      gpr_asprintf(&buffer, "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx%dx", shuf[j]);
+      gpr_asprintf(&buffer, "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx%" PRIuPTR "x",
+                   shuf[j]);
       test = grpc_mdstr_from_string(buffer);
       GPR_ASSERT(test == strs[shuf[j]]);
       GRPC_MDSTR_UNREF(test);
diff --git a/test/cpp/end2end/async_end2end_test.cc b/test/cpp/end2end/async_end2end_test.cc
index b839801500..8229bda6bf 100644
--- a/test/cpp/end2end/async_end2end_test.cc
+++ b/test/cpp/end2end/async_end2end_test.cc
@@ -229,9 +229,10 @@ class TestScenario {
         credentials_type(creds_type),
         message_content(content) {}
   void Log() const {
-    gpr_log(GPR_INFO,
-            "Scenario: disable_blocking %d, credentials %s, message size %d",
-            disable_blocking, credentials_type.c_str(), message_content.size());
+    gpr_log(
+        GPR_INFO,
+        "Scenario: disable_blocking %d, credentials %s, message size %" PRIuPTR,
+        disable_blocking, credentials_type.c_str(), message_content.size());
   }
   bool disable_blocking;
   const grpc::string credentials_type;
diff --git a/test/cpp/end2end/zookeeper_test.cc b/test/cpp/end2end/zookeeper_test.cc
index 12853a1b98..fdc500e535 100644
--- a/test/cpp/end2end/zookeeper_test.cc
+++ b/test/cpp/end2end/zookeeper_test.cc
@@ -101,7 +101,7 @@ class ZookeeperTest : public ::testing::Test {
       zookeeper_address_ = addr_str;
       gpr_free(addr);
     }
-    gpr_log(GPR_DEBUG, zookeeper_address_.c_str());
+    gpr_log(GPR_DEBUG, "%s", zookeeper_address_.c_str());
 
     // Connects to zookeeper server
     zoo_set_debug_level(ZOO_LOG_LEVEL_WARN);
diff --git a/test/cpp/interop/client.cc b/test/cpp/interop/client.cc
index 7727824979..addaf174f2 100644
--- a/test/cpp/interop/client.cc
+++ b/test/cpp/interop/client.cc
@@ -171,8 +171,9 @@ int main(int argc, char** argv) {
         "large_unary|large_compressed_unary|client_streaming|server_streaming|"
         "server_compressed_streaming|half_duplex|ping_pong|cancel_after_begin|"
         "cancel_after_first_response|timeout_on_sleeping_server|empty_stream|"
-        "compute_engine_creds|jwt_token_creds|oauth2_auth_token|per_rpc_creds",
-        "status_code_and_message|custom_metadata", FLAGS_test_case.c_str());
+        "compute_engine_creds|jwt_token_creds|oauth2_auth_token|per_rpc_creds|"
+        "status_code_and_message|custom_metadata",
+        FLAGS_test_case.c_str());
     ret = 1;
   }
 
diff --git a/test/cpp/interop/interop_client.cc b/test/cpp/interop/interop_client.cc
index a0479e8f68..0bf1fd6f73 100644
--- a/test/cpp/interop/interop_client.cc
+++ b/test/cpp/interop/interop_client.cc
@@ -433,7 +433,7 @@ bool InteropClient::DoResponseStreaming() {
     // most likely due to connection failure.
     gpr_log(GPR_ERROR,
             "DoResponseStreaming(): Read fewer streams (%d) than "
-            "response_stream_sizes.size() (%d)",
+            "response_stream_sizes.size() (%" PRIuPTR ")",
             i, response_stream_sizes.size());
     return TransientFailureOrAbort();
   }
@@ -517,9 +517,11 @@ bool InteropClient::DoResponseCompressedStreaming() {
         // stream->Read() failed before reading all the expected messages. This
         // is most likely due to a connection failure.
         gpr_log(GPR_ERROR,
-                "DoResponseCompressedStreaming(): Responses read (k=%d) is "
+                "DoResponseCompressedStreaming(): Responses read (k=%" PRIuPTR
+                ") is "
                 "less than the expected messages (i.e "
-                "response_stream_sizes.size() (%d)). (i=%d, j=%d)",
+                "response_stream_sizes.size() (%" PRIuPTR ")). (i=%" PRIuPTR
+                ", j=%" PRIuPTR ")",
                 k, response_stream_sizes.size(), i, j);
         return TransientFailureOrAbort();
       }
@@ -608,7 +610,7 @@ bool InteropClient::DoHalfDuplex() {
     // most likely due to a connection failure
     gpr_log(GPR_ERROR,
             "DoHalfDuplex(): Responses read (i=%d) are less than the expected "
-            "number of messages response_stream_sizes.size() (%d)",
+            "number of messages response_stream_sizes.size() (%" PRIuPTR ")",
             i, response_stream_sizes.size());
     return TransientFailureOrAbort();
   }
diff --git a/test/cpp/interop/metrics_client.cc b/test/cpp/interop/metrics_client.cc
index c8c2215fab..7a0cb994df 100644
--- a/test/cpp/interop/metrics_client.cc
+++ b/test/cpp/interop/metrics_client.cc
@@ -76,7 +76,7 @@ bool PrintMetrics(std::unique_ptr<MetricsService::Stub> stub, bool total_only,
   while (reader->Read(&gauge_response)) {
     if (gauge_response.value_case() == GaugeResponse::kLongValue) {
       if (!total_only) {
-        gpr_log(GPR_INFO, "%s: %ld", gauge_response.name().c_str(),
+        gpr_log(GPR_INFO, "%s: %lld", gauge_response.name().c_str(),
                 gauge_response.long_value());
       }
       overall_qps += gauge_response.long_value();
diff --git a/test/cpp/qps/driver.cc b/test/cpp/qps/driver.cc
index 57d8c22a95..83dbdc3e59 100644
--- a/test/cpp/qps/driver.cc
+++ b/test/cpp/qps/driver.cc
@@ -244,8 +244,8 @@ std::unique_ptr<ScenarioResult> RunScenario(
   // where class contained in std::vector must have a copy constructor
   auto* servers = new ServerData[num_servers];
   for (size_t i = 0; i < num_servers; i++) {
-    gpr_log(GPR_INFO, "Starting server on %s (worker #%d)", workers[i].c_str(),
-            i);
+    gpr_log(GPR_INFO, "Starting server on %s (worker #%" PRIuPTR ")",
+            workers[i].c_str(), i);
     servers[i].stub = WorkerService::NewStub(
         CreateChannel(workers[i], InsecureChannelCredentials()));
 
@@ -307,8 +307,8 @@ std::unique_ptr<ScenarioResult> RunScenario(
   auto* clients = new ClientData[num_clients];
   for (size_t i = 0; i < num_clients; i++) {
     const auto& worker = workers[i + num_servers];
-    gpr_log(GPR_INFO, "Starting client on %s (worker #%d)", worker.c_str(),
-            i + num_servers);
+    gpr_log(GPR_INFO, "Starting client on %s (worker #%" PRIuPTR ")",
+            worker.c_str(), i + num_servers);
     clients[i].stub = WorkerService::NewStub(
         CreateChannel(worker, InsecureChannelCredentials()));
     ClientConfig per_client_config = client_config;
diff --git a/test/cpp/qps/parse_json.cc b/test/cpp/qps/parse_json.cc
index be804281f8..e4fc35fa41 100644
--- a/test/cpp/qps/parse_json.cc
+++ b/test/cpp/qps/parse_json.cc
@@ -55,7 +55,7 @@ void ParseJson(const grpc::string& json, const grpc::string& type,
     grpc::string errmsg(status.error_message());
     gpr_log(GPR_ERROR, "Failed to convert json to binary: errcode=%d msg=%s",
             status.error_code(), errmsg.c_str());
-    gpr_log(GPR_ERROR, "JSON: ", json.c_str());
+    gpr_log(GPR_ERROR, "JSON: %s", json.c_str());
     abort();
   }
   GPR_ASSERT(msg->ParseFromString(binary));