Steps to reproduce:
1. Create a new Unity project
2. Set scripting backend to IL2CPP in Player Settings
3. Attempt to build the project

Expected result: Build succeeds
Actual result: Build fails due to missing file errors:
c1: fatal error C1083: Cannot open source file: 'Files\Unity\Hub\Editor\2021.2.0a8\Editor\Data\il2cpp\libil2cpp\pch\pch-c.h': No such file or directory
pch-c-14212280230507549953.cpp
C:\Users\username\Downloads\il2cpp\Library\il2cpp_cache\buildstate\y2vq\pch-c-14212280230507549953.cpp: fatal error C1083: Cannot open include file: 'C:\Program': No such file or directory

Workaround: Install Unity in a directory with no space in the path.

Reproduced with: 2021.2.0a8
Didn't reproduce with: 2021.1.0b11, 2020.3.0f1, 2019.4.22f1, 2018.4