Fix clang 11 and make icudata embed portable

.bazelrc

@@ -4,8 +4,8 @@ build --cxxopt='-stdlib=libc++' --host_cxxopt='-stdlib=libc++'
 build --linkopt='-stdlib=libc++' --host_linkopt='-stdlib=libc++'
 
 build --action_env=BAZEL_COMPILER=clang
-build --action_env=CC=/usr/lib/llvm-15/bin/clang
-build --action_env=CXX=/usr/lib/llvm-15/bin/clang++
+build --action_env=CC=clang
+build --action_env=CXX=clang++
 
 build --@capnp-cpp//src/kj:openssl=True --@capnp-cpp//src/kj:zlib=True --@capnp-cpp//src/kj:libdl=True
 
@@ -15,12 +15,10 @@ build --cxxopt='-Wextra' --host_cxxopt='-Wextra'
 build --cxxopt='-Wno-strict-aliasing' --host_cxxopt='-Wno-strict-aliasing'
 build --cxxopt='-Wno-sign-compare' --host_cxxopt='-Wno-sign-compare'
 build --cxxopt='-Wno-unused-parameter' --host_cxxopt='-Wno-unused-parameter'
-build --cxxopt='-Wno-deprecated-experimental-coroutine' --host_cxxopt='-Wno-deprecated-experimental-coroutine'
 build --cxxopt='-Wno-missing-field-initializers' --host_cxxopt='-Wno-missing-field-initializers'
 build --cxxopt='-Wno-ignored-qualifiers' --host_cxxopt='-Wno-ignored-qualifiers'
 
 # Our dependencies (ICU, zlib, etc.) produce a lot of these warnings, so we disable them.
 # TODO(cleanup): Can we disable warnings altogether from our dependencies, without disabling them
 #   for workerd?
 build --cxxopt='-Wno-ambiguous-reversed-operator' --host_cxxopt='-Wno-ambiguous-reversed-operator'
-build --copt='-Wno-deprecated-non-prototype' --host_copt='-Wno-deprecated-non-prototype'

BUILD.bazel

@@ -1,12 +1,10 @@
-load("//:build/wd_cc_embed.bzl", "wd_cc_embed")
+load("@capnp-cpp//src/capnp:cc_capnp_library.bzl", "cc_capnp_library")
 
-wd_cc_embed(
+cc_capnp_library(
     name = "icudata-embed",
-    base_name = "icudata-embed",
+    srcs = ["icudata-embed.capnp"],
     strip_include_prefix = "",
-    defines = [
-        "WORKERD_ICU_DATA_EMBED=EMBED_com_googlesource_chromium_icu_common_icudtl_dat"
-    ],
-    data = ["@com_googlesource_chromium_icu//:icudata"],
     visibility = ["//visibility:public"],
+    data = ["@com_googlesource_chromium_icu//:icudata"],
+    defines = [ "WORKERD_ICU_DATA_EMBED" ],
 )

README.md

@@ -70,8 +70,8 @@ Windows users should run `workerd` under WSL2.
 To build `workerd`, you need:
 
 * [Bazel](https://bazel.build/)
-* Clang 15
-* libc++ 15
+* Clang 11+ (e.g. package `clang` on Debian Bullseye)
+* libc++ 11+ (e.g. packages `libc++-dev` and `libc++abi-dev` on Debian Bullseye)
 
 You may then build using:
 

icudata-embed.capnp

@@ -0,0 +1,13 @@
+@0x9ed733e2dd15598b;
+# This file is a hack to embed the ICU data file which libicu needs at runtime to do its thing.
+# It's inconvenient to ship this file separately so we bake it into the binary. (V8's normal GN
+# build can actually do this for us, but we use the Bazel build which doesn't have this option.)
+#
+# We use Cap'n Proto to do the embedding because it's conveniently cross-platform, but this is
+# pretty ugly as it generates a 57MB C++ source file (containing a giant byte array literal).
+# It would be nice to use some more direct way of embedding binary data into a symbol in the
+# executable, but I couldn't figure out how to do this portably. (See the commit which introduced
+# this file to see the old Linux-only solution, but it didn't work on Mac and I didn't want to
+# figure it out.)
+
+const embeddedIcuDataFile :Data = embed "external/com_googlesource_chromium_icu/common/icudtl.dat";

src/workerd/api/r2-rpc.c++

@@ -113,7 +113,7 @@ kj::Promise<R2Result> doR2HTTPGetRequest(kj::Own<kj::HttpClient> client,
         });
       }
 
-      return result;
+      return kj::mv(result);
     }
 
     KJ_IF_MAYBE(m, response.headers->get(headerIds.cfBlobMetadataSize)) {

src/workerd/api/trace.c++

@@ -192,7 +192,7 @@ double TraceLog::getTimestamp() {
 
 kj::StringPtr TraceLog::getLevel() {
   switch (log.logLevel) {
-    case LogLevel::DEBUG: return "debug"_kj;
+    case LogLevel::DEBUG_: return "debug"_kj;
     case LogLevel::INFO: return "info"_kj;
     case LogLevel::LOG: return "log"_kj;
     case LogLevel::WARN: return "warn"_kj;

src/workerd/io/worker-interface.capnp

@@ -4,7 +4,8 @@
 
 @0xf7958855f6746344;
 
-$import "/capnp/c++.capnp".namespace("workerd::rpc");
+using Cxx = import "/capnp/c++.capnp";
+$Cxx.namespace("workerd::rpc");
 
 using import "/capnp/compat/http-over-capnp.capnp".HttpMethod;
 using import "/capnp/compat/http-over-capnp.capnp".HttpService;
@@ -17,7 +18,7 @@ struct Trace @0x8e8d911203762d34 {
 
     logLevel @1 :Level;
     enum Level {
-      debug @0;
+      debug @0 $Cxx.name("debug_");  # avoid collision with macro on Apple platforms
       info @1;
       log @2;
       warn @3;

src/workerd/io/worker.c++

@@ -624,7 +624,7 @@ struct Worker::Isolate::Impl {
           jsg::check(console.As<v8::Object>()->Set(context, methodStr, f));
         };
 
-        setHandler("debug", LogLevel::DEBUG);
+        setHandler("debug", LogLevel::DEBUG_);
         setHandler("error", LogLevel::ERROR);
         setHandler("info", LogLevel::INFO);
         setHandler("log", LogLevel::LOG);

src/workerd/jsg/iterator.h

@@ -156,13 +156,23 @@ class GeneratorImpl {
   friend Generator;
 };
 
+#if _LIBCPP_VERSION >= 15000
 template <class Func, class T>
 concept GeneratorCallback = std::invocable<Func, Lock&, T, GeneratorContext<T>&>
     && std::same_as<void, std::invoke_result_t<Func, Lock&, T, GeneratorContext<T>&>>;
 
 template <class Func, class T>
 concept AsyncGeneratorCallback = std::invocable<Func, Lock&, T, GeneratorContext<T>&>
     && std::same_as<Promise<void>, std::invoke_result_t<Func, Lock&, T, GeneratorContext<T>&>>;
+#else
+// These don't work in libc++ 11. I haven't tried 12-14, but they do work in 15. So we'll just
+// skip the extra type checking if we don't have libc++ 15 or newer.
+template <class Func, class T>
+concept GeneratorCallback = true;
+
+template <class Func, class T>
+concept AsyncGeneratorCallback = true;
+#endif
 
 template <typename T>
 class Generator final {

src/workerd/jsg/setup.c++

@@ -8,7 +8,7 @@
 #include <ucontext.h>
 
 #ifdef WORKERD_ICU_DATA_EMBED
-#include <icudata-embed.h>
+#include <icudata-embed.capnp.h>
 #include <unicode/udata.h>
 #endif
 
@@ -101,7 +101,7 @@ V8System::V8System(kj::Own<v8::Platform> platformParam, kj::ArrayPtr<const kj::S
   // ourselves. `WORKERD_ICU_DATA_EMBED`, if defined, will refer to a `kj::ArrayPtr<const byte>`
   // containing the data.
   UErrorCode err = U_ZERO_ERROR;
-  udata_setCommonData(WORKERD_ICU_DATA_EMBED.begin(), &err);
+  udata_setCommonData(EMBEDDED_ICU_DATA_FILE->begin(), &err);
   udata_setFileAccess(UDATA_ONLY_PACKAGES, &err);
   KJ_ASSERT(err == U_ZERO_ERROR);
 #else