Hadrian: could not execute: _build/stage1/lib/bin/_build/stage0/lib/bin/unlit

Summary

Running the testsuite with Hadrian results in a dozen of failures that look like this:

Compile failed (exit code 1) errors were:
ghc: could not execute: /home/int-index/Projects/ghc-ghc-43/_build/stage1/lib/bin/_build/stage0/lib/bin/unlit

Note that the path to unlit isn't right, it contains both _build/stage1/lib/bin/ and _build/stage0/lib/bin/ ― what's up with that?

Steps to reproduce

hadrian/build.sh --flavour=Quick test

Expected behavior

These tests should pass.

Environment

• GHC version used: HEAD
• Operating System: Linux
• System Architecture: x86_64