GHC bindist with DWARF support seems much slower than non-DWARF
Comparing the DWARF and non-DWARF binary distributions, I'm seeing times for a
cabal new-build --disable-profiling --disable-library-profiling all for a multi-library project showing e.g. 5:46.90 for DWARF, vs 3:56.40 for non-DWARF bindists.
I'm assuming this is unexpected since I don't see it proclaimed loudly anywhere.
I thought this was irrelevant, but I did try doing
cabal new-build ... --enable-debug-info=0 with the DWARF-supporting GHC but that didn't seem to improve compile time. I don't see anything relevant in my
Even more confused because I see the same slow timing (~ 5:45) for a
stack build in the same project, yet it looks like
stack pulls in a GHC without DWARF-compiled libs:
$ readelf --debug-dump $HOME/.stack/programs/x86_64-linux/ghc-8.6.3/lib/ghc-8.6.3/text-126.96.36.199/libHStext-188.8.131.52-ghc8.6.3.so | grep Version $
stack is compiling in a different way though, and the timing similarity is just a coincidence.
I first noticed this when building GHC from source. It seemed that uncommenting these caused the regression (though I haven't double-checked):
#GhcLibHcOpts += -g3 #GhcRtsHcOpts += -g3
Attached is the project repo I tested with (again, with
cabal new-clean && cabal new-build --disable-profiling --disable-library-profiling all).