From: Matthijs Kooijman <matthijs@stdin.nl>
Date: Wed, 10 Mar 2010 15:23:34 +0000 (+0100)
Subject: Don't inline == and /=.
X-Git-Url: https://git.stderr.nl/gitweb?a=commitdiff_plain;h=39c7a90c464192797000b109ad6c90154f2ff3ea;p=matthijs%2Fmaster-project%2Fc%CE%BBash.git

Don't inline == and /=.

This is a hack to prevent problems caused by the derived Eq instances.
This is not a real solution, though.
---

diff --git "a/c\316\273ash/CLasH/Normalize.hs" "b/c\316\273ash/CLasH/Normalize.hs"
index 4a5ceec..2fc34c6 100644
--- "a/c\316\273ash/CLasH/Normalize.hs"
+++ "b/c\316\273ash/CLasH/Normalize.hs"
@@ -338,6 +338,13 @@ inlinenonreptop = everywhere ("inlinenonrep", inlinebind ((Monad.liftM not) . is
 -- doesn't seem to set all those names as "system names", we apply some
 -- guessing here.
 inlinetoplevel, inlinetopleveltop :: Transform
+-- HACK: Don't inline == and /=. The default (derived) implementation
+-- for /= uses the polymorphic version of ==, which gets a dictionary
+-- for Eq passed in, which contains a reference to itself, resulting in
+-- an infinite loop in transformation. Not inlining == is really a hack,
+-- but for now it keeps things working with the most common symptom of
+-- this problem.
+inlinetoplevel expr@(Var f) | Name.getOccString f `elem` ["==", "/="] = return expr
 -- Any system name is candidate for inlining. Never inline user-defined
 -- functions, to preserve structure.
 inlinetoplevel expr@(Var f) | not $ isUserDefined f = do