Reproduction Steps:
1- Download attached "TestShader.shader".
2- Open a new Unity project and import downloaded shader.

Expected Result: Shader compiles without problems, or fails with errors.
Observed Result: Shader compiler crashes with error message:
"Shader compiler: internal error compiling shader snippet type=0 platform=4: Protocol error - failed to read correct magic number"

Reproducible: 5.6.0b5, 5.1.5f1

Note: Does not occur when C_MAXLIGHTCOUNT is less than 819. More specifically, when sum of all arrays' sizes is less than 4092. You can distribute this unevenly.
(TestShader.shader - line:31-40)