小编R D*_*R D的帖子

Javascript允许将缓冲区从源线程转移到Worker线程.否则,复制ArrayBuffer,然后传递给worker.传输缓冲区在源线程[1]中不可访问("neutered"):

// create data that can be transfered
var arr = new Uint8Array(5);

// outputs: 5
console.log(arr.buffer.byteLength);

var worker = new Worker("some_worker.js");

// transfer the buffer
worker.postMessage({arr: arr}, [arr.buff]);

// the buffer vanishes. is "Neutered"
// outputs: 0
console.log(arr.buffer.byteLength);

我想知道机制是如何工作的.然而,我很好奇它为何被引入.为什么工作线程之间没有共享数据,就像传统的线程模型一样,它允许多个线程访问同一个内存区域？

同一问题的其他措辞澄清:

为什么缓冲区在转移时会被阉割？/这种机制背后的原因是什么？/为什么介绍它？为什么工人之间不能共享内存区域？

我正在寻找可信和/或官方消息来源的答案.

[1] https://developer.mozilla.org/en/docs/Web/API/Worker/postMessage

当我尝试使用emcc将C代码编译为Javascript时,我收到以下错误:

emcc tests/hello_world.c 
CRITICAL root: fastcomp in use, but LLVM has not been built with the JavaScript backend as a target, llc reports:
===========================================================================
LLVM (http://llvm.org/):
  LLVM version 3.5.1
  Optimized build with assertions.
  Built Feb 22 2015 (00:08:56).
  Default target: x86_64-apple-darwin13.4.0
  Host CPU: corei7-avx

  Registered Targets:
    x86    - 32-bit X86: Pentium-Pro and above
    x86-64 - 64-bit X86: EM64T and AMD64
===========================================================================
CRITICAL root: you can fall back to the older (pre-fastcomp) compiler core, although that is not recommended, see https://github.com/kripken/emscripten/wiki/LLVM-Backend …