Hey all,
I'm trying to debug a segfault caused by my optimization. GHC only segfaults when compiled with -O2 and my flag, i.e., I used the "perf" flavour:
> ./hadrian/build -j "stage1.*.ghc.hs.opts += -fregs-ssa" --flavour=perf
However, I can't get a stack trace.
[1] suggests I need a profiling build for that. So I tried:
> ./hadrian/build -j "stage1.*.ghc.hs.opts += -fregs-ssa" --flavour=perf+debug_info+profiled_ghc+no_dynamic_ghc
Unfortunately, I'm using GHC 9.2.1 from ghcup to bootstrap and this version doesn't come with profiling enabled base [2].
8.10.7, which I have installed, can't compile ghc anymore (it seems). So I tried 9.2.3 from ghcup and that gives me the strangest errors. Basically, the compiler seems completely bricked.
I installed 9.2.3, ran "hadrian/build clean", "./configure && ./boot" and the same line as above with both "default" and "perf" flavours.
When I try to compile nofib/spectral/simple, I get:
> /home/ben/Projekte/haskell/ghc/_build/stage1/bin/ghc -O2 Main.hs
> [1 of 2] Compiling Main ( Main.hs, Main.o )
> Main.hs:1125:1: error: lexical error (UTF-8 decoding error)
(Main.hs only has 1124 lines though, file was not modified, compiles fine with any other ghc version)
But most programs I tried give me:
> /home/ben/Projekte/haskell/ghc/_build/stage1/bin/ghc -O2 Main.hs
> ghc: Unable to commit 283468890112 bytes of memory
> ghc: Exiting. The system might be out of memory.
Oh kay. I got 16GB RAM, 10 gig available. GHC 9.2.3 works fine.
Is my flavour combination bad, or what is broken here?