To reproduce:
1. Open the attached project;
2. Attempt to Build the project.

Expected result: Unity builds the project successfully, no shader compile errors were thrown (or meaningful errors were thrown)
Actual result: Build fails,
"Assertion failed: Shader compiler: internal error compiling shader snippet type=1 platform=1: Protocol error - failed to read correct magic number"
"Assertion failed: Shader Compiler Socket Exception: Terminating shader compiler process, 0 retries left" were thrown into the console.

Reproduced on versions: 5.5.6f1, 5.6.5f1, 2017.1.3f1, 2017.2.1p1.
Not reproduced on versions: 2017.3.0a1-2017.3.0a6.

Fixed on version: 2017.2.2p3, 2017.4.3f1.

DirectX9 is deprecated in 2017.3 - 2018.x versions