#16256: -fexternal-interpreter slow for profiling with template haskell -------------------------------------+------------------------------------- Reporter: guibou | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.6.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- I'm trying to build the following program (in `Foo.hs`) with profiling enabled: {{{#!haskell {-# LANGUAGE TemplateHaskell #-} main = print $([| 10 |]) }}} With the "alternate object file suffix" method, I have correct build time: {{{ $ time ghc -prof -osuf o_p Foo.hs [1 of 1] Compiling Main ( Foo.hs, Foo.o_p ) Linking Foo ... real 0m1.698s user 0m1.518s sys 0m0.184s }}} However with `-fexternal-interpreter`, times are abysmally slow: {{{ $ time ghc -prof -fexternal-interpreter -osuf "p_o" Foo.hs [1 of 1] Compiling Main ( Foo.hs, Foo.p_o ) Linking Foo ... real 0m26.077s user 0m1.531s sys 0m0.190s }}} I'm using `ghc-8.6.3` on nixos. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/16256 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler