Revert the protobuf update, which had broad fallout.

Instead, silence a zlib warning in the emsdk transition.

Signed-off-by: Martijn Stevenson <mstevenson@google.com>

.bazelrc

@@ -1,5 +1,3 @@
-# Required for emsdk: https://github.com/emscripten-core/emsdk/blob/main/bazel/README.md
+# Claimed to be required for emsdk:
+# https://github.com/emscripten-core/emsdk/blob/main/bazel/README.md
 build --incompatible_enable_cc_toolchain_resolution
-
-# C++14 or higher is required by Abseil, which is included from protobuf.
-build --cxxopt=-std=c++17 --host_cxxopt=-std=c++17

BUILD

@@ -13,6 +13,7 @@ cc_library(
         "proxy_wasm_api.h",
         "proxy_wasm_externs.h",
     ],
+    copts = ["-std=c++17"],
     deps = [
         ":common_lib",
         "@com_google_protobuf//:protobuf_lite",
@@ -25,6 +26,7 @@ cc_library(
         "proxy_wasm_common.h",
         "proxy_wasm_enums.h",
     ],
+    copts = ["-std=c++17"],
 )
 
 cc_library(
@@ -39,6 +41,7 @@ cc_library(
         "proxy_wasm_externs.h",
         "proxy_wasm_intrinsics.h",
     ],
+    copts = ["-std=c++17"],
     visibility = ["//visibility:public"],
 )
 
@@ -62,6 +65,7 @@ proto_library(
 cc_library(
     name = "proxy_wasm_intrinsics_lite",
     hdrs = ["proxy_wasm_intrinsics_lite.h"],
+    copts = ["-std=c++17"],
     defines = ["PROXY_WASM_PROTOBUF_LITE"],
     visibility = ["//visibility:public"],
     deps = [
@@ -75,6 +79,7 @@ cc_library(
 cc_library(
     name = "proxy_wasm_intrinsics_full",
     hdrs = ["proxy_wasm_intrinsics_full.h"],
+    copts = ["-std=c++17"],
     defines = ["PROXY_WASM_PROTOBUF_FULL"],
     visibility = ["//visibility:public"],
     deps = [

bazel/defs.bzl

@@ -22,8 +22,13 @@ def _optimized_wasm_cc_binary_transition_impl(settings, attr):
     # Define STANDALONE_WASM at compile time as well as link time (below).
     # This influences Abseil libraries using conditional dependencies.
     # TODO(martijneken): Remove after Abseil stops using this define.
+    #
+    # Disable warning -Wdeprecated-non-prototype for zlib:
+    # https://github.com/madler/zlib/issues/633
+    # This is fixed in more recent versions of zlib / protobuf.
+    # TODO(martijneken): Remove after protobuf version update.
     return {
-        "//command_line_option:copt": ["-O3", "-DSTANDALONE_WASM"],
+        "//command_line_option:copt": ["-O3", "-DSTANDALONE_WASM", "-Wno-deprecated-non-prototype"],
         "//command_line_option:cxxopt": [],
         "//command_line_option:linkopt": [],
         "//command_line_option:collect_code_coverage": False,

bazel/repositories.bzl

@@ -30,18 +30,7 @@ def proxy_wasm_cpp_sdk_repositories():
     maybe(
         http_archive,
         name = "com_google_protobuf",
-        sha256 = "a700a49470d301f1190a487a923b5095bf60f08f4ae4cac9f5f7c36883d17971",
-        strip_prefix = "protobuf-23.4",
-        url = "https://github.com/protocolbuffers/protobuf/releases/download/v23.4/protobuf-23.4.tar.gz",
-    )
-
-    # Update protobuf dependency to fix unused function CodepointSkipBackwards.
-    # https://github.com/protocolbuffers/utf8_range/commit/d863bc33e15cba6d873c878dcca9e6fe52b2f8cb
-    # TODO(martijneken): Remove this when protobuf picks up the fix.
-    maybe(
-        http_archive,
-        name = "utf8_range",
-        sha256 = "568988b5f7261ca181468dba38849fabf59dd9200fb2ed4b2823da187ef84d8c",
-        strip_prefix = "utf8_range-d863bc33e15cba6d873c878dcca9e6fe52b2f8cb",
-        url = "https://github.com/protocolbuffers/utf8_range/archive/d863bc33e15cba6d873c878dcca9e6fe52b2f8cb.zip",
+        sha256 = "77ad26d3f65222fd96ccc18b055632b0bfedf295cb748b712a98ba1ac0b704b2",
+        strip_prefix = "protobuf-3.17.3",
+        url = "https://github.com/protocolbuffers/protobuf/releases/download/v3.17.3/protobuf-all-3.17.3.tar.gz",
     )

example/BUILD

@@ -5,16 +5,19 @@ licenses(["notice"])  # Apache 2
 proxy_wasm_cc_binary(
     name = "http_wasm_example.wasm",
     srcs = ["http_wasm_example.cc"],
+    copts = ["-std=c++17"],
 )
 
 proxy_wasm_cc_binary(
     name = "http_wasm_example_with_protobuf_lite.wasm",
     srcs = ["http_wasm_example.cc"],
+    copts = ["-std=c++17"],
     protobuf = "lite",
 )
 
 proxy_wasm_cc_binary(
     name = "http_wasm_example_with_protobuf_full.wasm",
     srcs = ["http_wasm_example.cc"],
+    copts = ["-std=c++17"],
     protobuf = "full",
 )