#13739: Very slow linking of profiled executables -------------------------------------+------------------------------------- Reporter: duog | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1-rc2 Resolution: | Keywords: Operating System: Linux | Architecture: x86_64 Type of failure: Compile-time | (amd64) performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by niteria): I'm getting 2 minute compile times when linking profiled GHC HEAD. Running with `-v` reveals that GHC is stuck on gcc doing linking Here's the stuck command: https://phabricator.haskell.org/P151, it takes 135s to complete. When I remove `-Wl,--gc-sections`, it's only 11s. It's part of this GHC invocation: {{{ "inplace/bin/ghc-stage1" -o ghc/stage2/build/tmp/ghc-stage2 -hisuf p_hi -osuf p_o -hcsuf p_hc -static -prof -eventlog -O0 -H64m -Wall -hide-all-packages - i -ighc/. -ighc/stage2/build -Ighc/stage2/build -ighc/stage2/build/ghc/autogen -Ighc/stage2/build/ghc/autogen -optP- DGHCI -optP-include -optPghc/stage2/build/ghc/autogen/cabal_macros.h -package-id base-4.10.0.0 -package-id array-0.5.1.2 -package-id bytestring-0.10.8.2 -package-id directory-1.3.0.2 -package-id process-1.6.0.0 -package-id filepath-1.4.1.2 -pack age-id ghc-boot-8.3 -package-id ghc-8.3 -package-id unix-2.7.2.2 -package- id containers-0.5.10.2 -package-id deepseq-1.4.3.0 -package-id ghci-8.3 -package-id haskeline-0.7.4.0 -packa ge-id time-1.8.0.1 -package-id transformers-0.5.2.0 -Wall -fno-warn-name- shadowing -XHaskell2010 -O -no-hs-main -threaded -no-user-package-db -rtsopts -Wnoncanonical-monad-inst ances -odir ghc/stage2/build -hidir ghc/stage2/build -stubdir ghc/stage2/build -split-sections -static -prof -eventlog -O0 -H64m -Wall -hide-all-packages -i -ighc/. -ighc/ stage2/build -Ighc/stage2/build -ighc/stage2/build/ghc/autogen -Ighc/stage2/build/ghc/autogen -optP-DGHCI -optP-include -optPghc/stage2/build/ghc/autogen/cabal_macros.h -package-id base-4.10.0.0 -package-id array-0.5.1.2 -package-id bytestring-0.10.8.2 -package-id directory-1.3.0.2 -package-id process-1.6.0.0 -package-id filepath-1.4.1.2 -package-id ghc-boot- 8.3 -package-id ghc-8.3 -package-id unix-2.7.2.2 -package-id containers-0.5.10.2 -package-id deepseq-1.4.3.0 -package-id ghci-8.3 -package-id haskeline-0.7.4.0 -package-id time-1.8.0 .1 -package-id transformers-0.5.2.0 -Wall -fno-warn-name-shadowing -XHaskell2010 -O -no-hs-main -threaded -no-user-package-db -rtsopts -Wnoncanonical-monad-instances ghc/stage 2/build/Main.p_o ghc/stage2/build/GHCi/UI.p_o ghc/stage2/build/GHCi/UI/Info.p_o ghc/stage2/build/GHCi/UI/Monad.p_o ghc/stage2/build/GHCi/UI/Tags.p_o ghc/stage2/build/hschooks.p_o -v -keep- tmp-files }}} My gcc version: {{{ $ gcc --version gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-11) Copyright (C) 2015 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. }}} @doug: Can you run the command that hangs with: `cabal build cabal-install --ghc-options='-v'` to check if it's an instance of the same problem? If it's also stuck on `gcc` you can run it with `cabal build cabal-install --ghc-options='-v -keep-tmp-files'` and run the `gcc` command by itself. Then try removing `-Wl,--gc-sections`. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13739#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler