the impossible pprPanic, called at compiler/cmm/CmmLive.hs:70:8 in ghc:CmmLive
Summary
Whilst upgrading our project to use 8.8.1 to avoid a bug in 8.6.5 I encountered the following. I had everything building with -O0
and then tried to do an -O2
build but received this.
ghc: panic! (the 'impossible' happened)
(GHC version 8.8.1 for x86_64-unknown-linux):
LocalReg's live-in to graph
cxl1 {_svLx::P64, _svLy::P64, _svLz::P64, _svLA::P64, _svLB::P64}
Call stack:
CallStack (from HasCallStack):
callStackDoc, called at compiler/utils/Outputable.hs:1159:37 in ghc:Outputable
pprPanic, called at compiler/cmm/CmmLive.hs:70:8 in ghc:CmmLive
Whilst trying to remove code (there's a lot) to produce something shareable i removed {-# INLINE f #-}
from some functions and the error went away.
I do not yet have a small reproduction but am able to try any suggestions
Steps to reproduce
compile my code with -O1
or -O2
Expected behavior
it to build
Environment
- GHC version used: 8.8.1
Optional:
- Operating System: ubuntu 18.04
- System Architecture: x86_64