Suppress many compiler warnings

This includes ~200 -Wsign-compare warnings in TensorFlow, 15
-Wimplicit-function-declaration warnings in zlib, and more.

I'm also working on getting rid of 400 protobuf warnings here:
protocolbuffers/protobuf#2261
Change: 136555503

tensorflow/contrib/metrics/kernels/BUILD

@@ -10,6 +10,7 @@ package(default_visibility = ["//tensorflow:__subpackages__"])
 cc_library(
     name = "set_kernels",
     srcs = ["set_kernels.cc"],
+    copts = ["-Wno-sign-compare"],
     deps = [
         "//tensorflow/core:framework_headers_lib",
         "//third_party/eigen3",

tensorflow/contrib/tfprof/tools/tfprof/internal/BUILD

@@ -122,6 +122,7 @@ cc_library(
     name = "tfprof_utils",
     srcs = ["tfprof_utils.cc"],
     hdrs = ["tfprof_utils.h"],
+    copts = ["-Wno-sign-compare"],
     deps = [
         ":tfprof_options",
         "//tensorflow/core:lib",
@@ -182,6 +183,7 @@ cc_library(
     name = "tfprof_tensor",
     srcs = ["tfprof_tensor.cc"],
     hdrs = ["tfprof_tensor.h"],
+    copts = ["-Wno-sign-compare"],
     deps = [
         "//tensorflow/contrib/tfprof/tools/tfprof:protos_all_cc",
         "//tensorflow/core:framework",

tensorflow/core/kernels/BUILD

@@ -205,6 +205,7 @@ cc_library(
     name = "ops_util",
     srcs = ["ops_util.cc"],
     hdrs = ["ops_util.h"],
+    copts = ["-Wno-sign-compare"],
     deps = [
         "//tensorflow/core:framework",
         "//tensorflow/core:lib",
@@ -288,6 +289,7 @@ cc_library(
     name = "save_restore_tensor",
     srcs = ["save_restore_tensor.cc"],
     hdrs = ["save_restore_tensor.h"],
+    copts = ["-Wno-sign-compare"],
     deps = [
         ":bounds_check",
         "//tensorflow/core:framework",

tensorflow/core/platform/default/build_config.bzl

@@ -46,6 +46,7 @@ def tf_proto_library_cc(name, srcs = [], has_services = None,
       srcs = srcs + tf_deps(deps, "_proto_srcs"),
       deps = deps + ["@protobuf//:cc_wkt_protos"],
       cc_libs = cc_libs + ["@protobuf//:protobuf"],
+      copts = ["-Wno-unused-but-set-variable", "-Wno-sign-compare"],
       protoc = "@protobuf//:protoc",
       default_runtime = "@protobuf//:protobuf",
       use_grpc_plugin = use_grpc_plugin,

tensorflow/core/util/tensor_bundle/BUILD

@@ -24,6 +24,7 @@ cc_library(
     name = "tensor_bundle",
     srcs = ["tensor_bundle.cc"],
     hdrs = ["tensor_bundle.h"],
+    copts = ["-Wno-sign-compare"],
     deps = [
         ":naming",
         "//tensorflow/core:core_cpu_internal",

tensorflow/python/BUILD

@@ -175,6 +175,7 @@ cc_library(
 cc_binary(
     name = "framework/test_file_system.so",
     srcs = ["framework/test_file_system.cc"],
+    copts = ["-Wno-sign-compare"],
     linkopts = select({
         "//conditions:default": [
             "-lm",
@@ -217,6 +218,7 @@ cc_library(
     name = "cpp_shape_inference",
     srcs = ["framework/cpp_shape_inference.cc"],
     hdrs = ["framework/cpp_shape_inference.h"],
+    copts = ["-Wno-sign-compare"],
     visibility = ["//visibility:public"],
     deps = [
         ":numpy_lib",

tensorflow/tensorflow.bzl

@@ -142,9 +142,10 @@ def if_not_mobile(a):
   })
 
 def tf_copts():
-  return (["-fno-exceptions",
-           "-DEIGEN_AVOID_STL_ARRAY",
-           "-Iexternal/gemmlowp",] +
+  return (["-DEIGEN_AVOID_STL_ARRAY",
+           "-Iexternal/gemmlowp",
+           "-Wno-sign-compare",
+           "-fno-exceptions"] +
           if_cuda(["-DGOOGLE_CUDA=1"]) +
           if_android_arm(["-mfpu=neon"]) +
           select({
@@ -155,7 +156,7 @@ def tf_copts():
                   "-O2",
               ],
               "//tensorflow:darwin": [],
-              "//tensorflow:ios": ["-std=c++11",],
+              "//tensorflow:ios": ["-std=c++11"],
               "//conditions:default": ["-pthread"]}))
 
 def tf_opts_nortti_if_android():
@@ -770,7 +771,9 @@ def tf_py_wrap_cc(name, srcs, swig_includes=[], deps=[], copts=[], **kwargs):
   native.cc_binary(
       name=cc_library_name,
       srcs=[module_name + ".cc"],
-      copts=(copts + ["-Wno-self-assign", "-Wno-write-strings"]
+      copts=(copts + ["-Wno-self-assign",
+                      "-Wno-sign-compare",
+                      "-Wno-write-strings"]
              + tf_extension_copts()),
       linkopts=tf_extension_linkopts() + extra_linkopts,
       linkstatic=1,

zlib.BUILD

@@ -32,5 +32,6 @@ cc_library(
         "zutil.h",
     ],
     hdrs = ["zlib.h"],
+    copts = ["-Wno-implicit-function-declaration"],
     includes = ["."],
 )