add a dedicated section for compiler environment variables in the unstable book#141526

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bors merged 2 commits intorust-lang:masterfrom

jyn514:env-vars

May 26, 2025

Commits on May 24, 2025

document existing setup
jyn514
committed

Commits on May 25, 2025

add "Compiler environment variables" section to the unstable book
jyn514
committed