#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 RyanGlScott): For reference, I decided to compare two builds of GHC 8.2.1-rc2 with and without reverting commit 283acec1d7307fdbd8cd7b3f1d984a036366d6b4, and the difference is astounding. If you revert commit 283acec1d7307fdbd8cd7b3f1d984a036366d6b4, you get: {{{ (Without -fwhole-archive-hs-libs) real 0m0.277s user 0m0.224s sys 0m0.036s (With -fwhole-archive-hs-libs) real 0m5.447s user 0m5.104s sys 0m0.328s }}} And if you use plain 8.2.1-rc2 (without reverting commit 283acec1d7307fdbd8cd7b3f1d984a036366d6b4), you get: {{{ (Without -fwhole-archive-hs-libs) real 0m13.648s user 0m12.716s sys 0m0.156s (With -fwhole-archive-hs-libs) real 0m3.077s user 0m2.500s sys 0m0.216s }}} So that commit at least explains the differences without the use of the `-fwhole-archive-hs-libs` flag. However, it doesn't account for the jump in times _with_ the the `-fwhole-archive-hs-libs` flag. I'll try investigating that next. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13739#comment:11 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler