From 6acec6bf34b19821da7a4605586d0c1a5f340454 Mon Sep 17 00:00:00 2001 From: John MacFarlane Date: Mon, 23 Apr 2018 12:02:59 -0700 Subject: CONTRIBUTING.md: added note about --trace. --- CONTRIBUTING.md | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'CONTRIBUTING.md') diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md index 1145dd835..11a0c9c94 100644 --- a/CONTRIBUTING.md +++ b/CONTRIBUTING.md @@ -205,6 +205,10 @@ placed in the source directory): Profiling --------- +To diagnose a performance issue with parsing, first try using +the `--trace` option. This will give you a record of when block +parsers succeed, so you can spot backtracking issues. + To use the GHC profiler with cabal: cabal clean -- cgit v1.2.3