Use include_bytes! instead of incbin. (#1182)

BUILD.gn

@@ -143,40 +143,12 @@ rust_executable("deno") {
 }
 
 source_set("snapshot") {
-  sources = [
-    "src/snapshot.cc",
-  ]
-  configs += [ ":deno_config" ]
   inputs = [
     "$target_gen_dir/snapshot_deno.bin",
   ]
   deps = [
     ":create_snapshot_deno",
   ]
-
-  # snapshot.cc doesn't need to depend on libdeno, it just needs deno_buf.
-  include_dirs = [ "libdeno/" ]
-
-  # src/snapshot.cc uses an assembly '.incbin' directive to embed the snapshot.
-  # This causes trouble when using sccache: since the snapshot file is not
-  # inlined by the c preprocessor, sccache doesn't take its contents into
-  # consideration, leading to false-positive cache hits.
-  # Maybe other caching tools have this issue too, but ccache is unaffected.
-  # Therefore, if a cc_wrapper is used that isn't ccache, include a generated
-  # header file that contains the the sha256 hash of the snapshot.
-  if (cc_wrapper != "" && cc_wrapper != "ccache") {
-    hash_h = "$target_gen_dir/bundle/hash.h"
-    inputs += [ hash_h ]
-    deps += [ ":bundle_hash_h" ]
-    if (is_win) {
-      cflags = [ "/FI" + rebase_path(hash_h, target_out_dir) ]
-    } else {
-      cflags = [
-        "-include",
-        rebase_path(hash_h, target_out_dir),
-      ]
-    }
-  }
 }
 
 rust_executable("hyper_hello") {

src/isolate.rs

@@ -139,7 +139,7 @@ impl Isolate {
     });
     let shared = empty(); // TODO Use shared for message passing.
     let libdeno_isolate = unsafe {
-      libdeno::deno_new(snapshot::deno_snapshot.clone(), shared, pre_dispatch)
+      libdeno::deno_new(snapshot::deno_snapshot(), shared, pre_dispatch)
     };
     // This channel handles sending async messages back to the runtime.
     let (tx, rx) = mpsc::channel::<(i32, Buf)>();

src/snapshot.cc

@@ -1,18 +0,0 @@
-// Copyright 2018 the Deno authors. All rights reserved. MIT license.
-
-#include "deno.h"
-
-extern "C" {
-
-extern const char snapshot_start asm("snapshot_start");
-extern const char snapshot_end asm("snapshot_end");
-asm(".data\n"
-    "snapshot_start: .incbin \"gen/snapshot_deno.bin\"\n"
-    "snapshot_end:\n"
-    ".globl snapshot_start;\n"
-    ".globl snapshot_end;");
-extern const deno_buf deno_snapshot = {
-  nullptr, 0, reinterpret_cast<uint8_t*>(const_cast<char*>(&snapshot_start)),
-  static_cast<size_t>(&snapshot_end - &snapshot_start)};
-
-}

src/snapshot.rs

@@ -1,5 +1,19 @@
 // Copyright 2018 the Deno authors. All rights reserved. MIT license.
 use libdeno::deno_buf;
-extern "C" {
-  pub static deno_snapshot: deno_buf;
+use std;
+
+pub fn deno_snapshot() -> deno_buf {
+  let data =
+    include_bytes!(concat!(env!("GN_OUT_DIR"), "/gen/snapshot_deno.bin"));
+  let ptr = data.as_ptr();
+  // TODO The transmute is not necessary here. deno_buf specifies mutable
+  // pointers when it doesn't necessarally need mutable. So maybe the deno_buf
+  // type should be broken into a mutable and non-mutable version?
+  let ptr_mut = unsafe { std::mem::transmute::<*const u8, *mut u8>(ptr) };
+  deno_buf {
+    alloc_ptr: std::ptr::null_mut(),
+    alloc_len: 0,
+    data_ptr: ptr_mut,
+    data_len: data.len(),
+  }
 }