GHC newcomer here -- attempting to work on my first patch.

I decided to try Hadrian, but ran into a problem.

I think I obtained the source using 
> git clone --recursive https://gitlab.haskell.org/ghc/ghc
Then:
> ./boot && ./configure
> hadrian/build.sh -j --flavour=devel2

This ran for maybe 15 minutes, then showed the error below. Apparently I ended up with too many tarballs? Any suggestions?

Thanks,
Eric

... 
 ...
| Run Ghc CompileCWithGhc Stage1: rts/Inlines.c => _build/stage1/rts/build/c/Inlines.thr_o
| Run Cc FindCDependencies Stage1: rts/Compact.cmm => _build/stage1/rts/build/cmm/Compact.o.d
| Run Cc FindCDependencies Stage1: rts/PathUtils.c => _build/stage1/rts/build/c/PathUtils.o.d
| Run Ghc CompileHs Stage1: rts/Compact.cmm => _build/stage1/rts/build/cmm/Compact.o
| Run Ghc CompileCWithGhc Stage1: rts/PathUtils.c => _build/stage1/rts/build/c/PathUtils.o
| Remove file _build/stage1/rts/build/libHSrts-1.0.a
| Run Ar Pack Stage1: _build/stage1/rts/build/c/Adjustor.o (and 113 more) => _build/stage1/rts/build/libHSrts-1.0.a
/usr/bin/ar: creating _build/stage1/rts/build/libHSrts-1.0.a
/---------------------------------------------------\
| Successfully built library 'rts' (Stage1, way v). |
| Library: _build/stage1/rts/build/libHSrts-1.0.a   |
\---------------------------------------------------/
| Remove file _build/stage1/rts/build/libHSrts-1.0_thr.a
| Run Ar Pack Stage1: _build/stage1/rts/build/c/Adjustor.thr_o (and 115 more) => _build/stage1/rts/build/libHSrts-1.0_thr.a
/usr/bin/ar: creating _build/stage1/rts/build/libHSrts-1.0_thr.a
/-----------------------------------------------------\
| Successfully built library 'rts' (Stage1, way thr). |
| Library: _build/stage1/rts/build/libHSrts-1.0_thr.a |
\-----------------------------------------------------/
| Copy file: _build/generated/ghcplatform.h => _build/stage1/rts/build/ghcplatform.h
| Copy file: _build/generated/ghcversion.h => _build/stage1/rts/build/ghcversion.h
| Copy file: _build/generated/DerivedConstants.h => _build/stage1/rts/build/DerivedConstants.h
| Copy file: _build/generated/ghcautoconf.h => _build/stage1/rts/build/ghcautoconf.h
| Remove directory _build/stage1/libffi/build
shakeArgsWith    0.000s    0%
Function shake   0.005s    0%
Database read    0.000s    0%
With database    0.000s    0%
Running rules  548.377s   99%  =========================
Total          548.383s  100%
Error when running Shake build system:
  at src/Rules.hs:(35,19)-(52,17):
  at src/Rules.hs:52:5-17:
* Depends on: _build/stage1/lib/package.conf.d/rts-1.0.conf
  at src/Rules/Register.hs:(94,9)-(98,34):
* Depends on: _build/stage1/rts/build/ffi.h
  at src/Rules/Libffi.hs:(49,7)-(52,48):
* Depends on: _build/stage1/rts/build/ffi.h _build/stage1/rts/build/ffitarget.h
  at src/Rules/Libffi.hs:52:13-48:
* Depends on: _build/stage1/libffi/build/inst/lib/libffi.a
  at src/Hadrian/Builder.hs:70:5-23:
* Depends on: _build/stage1/libffi/build/Makefile
  at src/Rules/Libffi.hs:107:9-27:
* Depends on: _build/stage1/libffi/build/Makefile.in
* Raised the exception:
Exactly one LibFFI tarball is expected
CallStack (from HasCallStack):
  error, called at src/Hadrian/Utilities.hs:60:27 in main:Hadrian.Utilities