hledger-lib 0.27.1 benchmark build failure (ghc bug)

[DanBurton]

> /tmp/stackage-build7/hledger-lib-0.27.1$ runghc -clear-package-db -global-pack
age-db -package-db=/home/stackage/work/builds/nightly/pkgdb Setup build
Building hledger-lib-0.27.1...
Preprocessing library hledger-lib-0.27.1...
[ 7 of 36] Compiling Hledger.Utils.Debug ( Hledger/Utils/Debug.hs, dist/build/Hl
edger/Utils/Debug.o ) [dist/build/autogen/cabal_macros.h changed]
[ 9 of 36] Compiling Hledger.Data.Types ( Hledger/Data/Types.hs, dist/build/Hled
ger/Data/Types.o ) [dist/build/autogen/cabal_macros.h changed]
[12 of 36] Compiling Hledger.Data.Dates ( Hledger/Data/Dates.hs, dist/build/Hledger/Data/Dates.o ) [dist/build/autogen/cabal_macros.h changed]
[14 of 36] Compiling Hledger.Data.Amount ( Hledger/Data/Amount.hs, dist/build/Hledger/Data/Amount.o ) [dist/build/autogen/cabal_macros.h changed]
[18 of 36] Compiling Hledger.Data.TimeLog ( Hledger/Data/TimeLog.hs, dist/build/Hledger/Data/TimeLog.o ) [dist/build/autogen/cabal_macros.h changed]
[24 of 36] Compiling Hledger.Read.JournalReader ( Hledger/Read/JournalReader.hs, dist/build/Hledger/Read/JournalReader.o ) [dist/build/autogen/cabal_macros.h changed]
[25 of 36] Compiling Hledger.Read.CsvReader ( Hledger/Read/CsvReader.hs, dist/build/Hledger/Read/CsvReader.o ) [dist/build/autogen/cabal_macros.h changed]
ghc: panic! (the 'impossible' happened)
  (GHC version 8.0.1 for x86_64-unknown-linux):
        Simplifier ticks exhausted
  When trying UnfoldingDone $s$fStream[]mtok_$cp1Stream_s3H5y
  To increase the limit, use -fsimpl-tick-factor=N (default 100)
  If you need to do this, let GHC HQ know, and what factor you needed
  To see detailed counts use -ddump-simpl-stats
  Total ticks: 523880

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

[RyanGlScott]

Pinging @simonmichael

[simonmichael]

I'm not able to reproduce this. Benchmarks with GHC 8 work normally here (and hledger-lib doesn't even have a benchmark):

~$ stack --resolver nightly-2016-07-19 bench hledger-lib 
Run from outside a project, using implicit global project config
Using resolver: nightly-2016-07-19 specified on command line
~$ stack --resolver nightly-2016-07-19 bench hledger
Run from outside a project, using implicit global project config
Using resolver: nightly-2016-07-19 specified on command line
hledger-0.27.1: download
hledger-0.27.1: configure
hledger-0.27.1: build
hledger-0.27.1: copy/register
~$ cd src/hledger
~/src/hledger$ stack --stack-yaml stack-ghc8.yaml --resolver nightly-2016-07-19 bench hledger-lib
~/src/hledger$ stack --stack-yaml stack-ghc8.yaml --resolver nightly-2016-07-19 bench hledger
hledger-0.28: benchmarks
Running 1 benchmarks...
Benchmark bench: RUNNING...
Benchmarking hledger in /Users/simon/src/hledger/hledger with timeit
read bench/10000x1000x10.journal        [1.49s]
print                                   [1.26s]
register                                [1.64s]
balance                                 [0.15s]
stats                                   [0.14s]
Total: 4.68s
Benchmark bench: FINISH

[simonmichael]

Oh good, now it's doing it and I can dig further.

[simonmichael]

It became severe at a time when I was doing concurrent GHC 7 and GHC 8 builds of project and deps. The GHC 8 build started giving the error for stack build, test or bench. stack clean made the error go away (and the other build had finished, if it matters) and I have not been able to reproduce it. I'm pretty sure adding hledger-lib to skipped-benchmarks is not the true fix.

[simonmichael]

Related GHC issues:

• https://ghc.haskell.org/trac/ghc/ticket/5539
• https://ghc.haskell.org/trac/ghc/ticket/8613
• https://ghc.haskell.org/trac/ghc/ticket/11263

These all seem to suggest reducing INLINE pragmas, but there aren't any of those in hledger.

[bergmark]

The test suite failed so I'll disable it as well