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lookupIdSubst panic with GHC 9.4.5 (#23762) · Issues · Glasgow Haskell Compiler / GHC · GitLab
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lookupIdSubst panic with GHC 9.4.5
Summary
GHC 9.4.5 panics with lookupIdSubst when building a benchmark of my library.
[2 of 3] Compiling IGA ( benchmark/IGA.hs, /tmp/haskell-floating-point/dist-newstyle/build/x86_64-linux/ghc-9.4.5/rounded-hw-0.3.0/build/rounded-hw-benchmark/rounded-hw-benchmark-tmp/IGA.o )
<no location info>: error:
panic! (the 'impossible' happened)
GHC version 9.4.5:
lookupIdSubst
df_sfFs
InScope {$dUnbox_X0 $dIArray_Xf $dFractional_Xg $dIArray_adxd
df_adxe $dUnbox_adxf $dFractional_adxs $dIArray_adxt df_adxu
$dUnbox_adxv $sintervalGaussianEliminationU_ddPi
$sintervalGaussianEliminationU_ddPj
$sintervalGaussianEliminationU_ddPk intervalGaussianElimination
intervalGaussianEliminationU benchmark $trModule $trModule_seOB
$trModule_seOC $trModule_seOD $trModule_seOE loc_seOF loc_seOG
loc_seOH loc_seOI loc_seOJ loc_seOK loc_seOL $dIP_seOM $dIP_seON
$dIP_seOO loc_seRU loc_seRV loc_seRW loc_seRX loc_seRY loc_seRZ
loc_seS0 $dIP_seS1 $dIP_seS2 $dIP_seS3 loc_seZA loc_seZB loc_seZC
loc_seZD loc_seZE loc_seZF loc_seZG $dIP_seZH $dIP_seZI $dIP_seZJ
benchmark_sfzR benchmark_sfzS}
Call stack:
CallStack (from HasCallStack):
callStackDoc, called at compiler/GHC/Utils/Panic.hs:182:37 in ghc:GHC.Utils.Panic
pprPanic, called at compiler/GHC/Core/Subst.hs:260:17 in ghc:GHC.Core.Subst
Please report this as a GHC bug: https://www.haskell.org/ghc/reportabug
Error: cabal: Failed to build rounded-hw-0.3.0.Steps to reproduce
$ git clone https://github.com/minoki/haskell-floating-point.git
$ cd haskell-floating-point/
$ cabal build -w ghc-9.4.5 --enable-benchmarks rounded-hwExpected behavior
The benchmark should build fine.
Environment
- GHC version used: 9.4.5
The GHC built from https://gitlab.haskell.org/ghc/ghc/-/commits/wip/9.4.6-backports/ is also affected, so this is a different issue from #22761 (closed).
Other series (9.2.x, 9.6.x, 9.8.1-alpha1) are not affected.
Optional:
- Operating System: x86_64 and AArch64
- System Architecture: Linux and macOS
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