WebGL Error: Not all control paths return a value
<p>Some of my clients are failing to initialize a webGL program. I'm catching the error with</p>

<pre><code>gl.linkProgram(program);

if (!gl.getProgramParameter(program, gl.LINK_STATUS)) {
  throw new Error("Unable to initialize the shader program: " + gl.getProgramInfoLog(program));
}
</code></pre>

<p>The log I'm getting is</p>

<pre><code>Unable to initialize the shader program:
C:\fakepath(72,30-133): error X3507: '_directionToColor':
  Not all control paths return a value
</code></pre>

<p>I've not been able to reproduce this error on my computer. Does anyone has an idea of what is going wrong? I'm happy to share more code if that's helpful :)</p>