Hadrian fails to run the test suite

Summary

Hadrian complains it can't find a (existing) ghc executable:

Andi@Horzube MINGW64 /e/ghc_exportTags
$ bash hadrian/build.sh --flavour=quick -o_quick -j9 --no-colour
Up to date
shakeArgsWith                        0.001s    0%
Function shake                       0.011s    0%
Database read                        0.285s    9%  ==
With database                        0.019s    0%
Running rules                        2.787s   89%  =========================
Pool finished (5015 threads, 9 max)  0.002s    0%
Cleanup                              0.000s    0%
Total                                3.104s  100%
Build completed in 3.10s


Andi@Horzube MINGW64 /e/ghc_exportTags
$ bash hadrian/build.sh -j9 --no-colour test
Up to date
| Configure package 'template-haskell'
| Configure package 'directory'
| Configure package 'ghc-prim'
| Configure package 'Cabal'
| Configure package 'Win32'
| Configure package 'ghc-compact'
| Configure package 'rts'
| Configure package 'mtl'
| Configure package 'time'
| Configure package 'bytestring'
| Configure package 'parsec'
| Configure package 'ghc-boot'
| Configure package 'xhtml'
| Configure package 'binary'
| Configure package 'transformers'
| Configure package 'ghci'
# cabal-read (for OracleQ (PackageDataKey (Package {pkgType = Program, pkgName = "hp2ps", pkgPath = "utils/hp2ps"})))
| Configure package 'containers'
# cabal-read (for OracleQ (PackageDataKey (Package {pkgType = Program, pkgName = "deriveConstants", pkgPath = "utils/deriveConstants"})))
| Configure package 'array'
# ghc (for _build/test/bin/ghc-config.exe)
Error when running Shake build system:
  at want, called at src\Main.hs:89:30 in main:Main
* Depends on: test
  at need, called at src\Rules\Test.hs:168:9 in main:Rules.Test
* Depends on: _build/test/ghcconfig
  at need, called at src\Rules\Test.hs:71:13 in main:Rules.Test
* Depends on: _build/test/bin/ghc-config.exe
* Raised the exception:
/opt/ghc/bin/ghc.exe: createProcess: does not exist (No such file or directory)

$ bash hadrian/build.sh --flavour=quick -o_quick -j9 --no-colour test
Up to date
# ghc (for _quick/test/bin/ghc-config.exe)
Error when running Shake build system:
  at want, called at src\Main.hs:89:30 in main:Main
* Depends on: test
  at need, called at src\Rules\Test.hs:168:9 in main:Rules.Test
* Depends on: _quick/test/ghcconfig
  at need, called at src\Rules\Test.hs:71:13 in main:Rules.Test
* Depends on: _quick/test/bin/ghc-config.exe
* Raised the exception:
/opt/ghc/bin/ghc.exe: createProcess: does not exist (No such file or directory)


Andi@Horzube MINGW64 /e/ghc_exportTags
$ /opt/ghc/bin/ghc.exe --version
The Glorious Glasgow Haskell Compilation System, version 8.6.5

Steps to reproduce

bash hadrian/build.sh --flavour=quick -o_quick -j9 --no-colour
bash hadrian/build.sh --flavour=quick -o_quick -j9 --no-colour test

Expected behavior

Run the testsuite

Environment

• Operating System: Windows