From 47f99500e68e40f34a1dab8b0350f32c2ed62d9d Mon Sep 17 00:00:00 2001 From: Daniel Llorens Date: Thu, 4 Nov 2021 16:02:42 +0100 Subject: [PATCH 2/2] Avoid ash with arguments that might overflow in (language cps types) Fixes https://debbugs.gnu.org/50609 * module/languages/cps/types.scm (ulsh): As stated. --- module/language/cps/types.scm | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/module/language/cps/types.scm b/module/language/cps/types.scm index d3be176bf..87c58d5bc 100644 --- a/module/language/cps/types.scm +++ b/module/language/cps/types.scm @@ -1444,7 +1444,9 @@ minimum, and maximum." (define! result &s64 &s64-min &s64-max)))) (define-type-inferrer (ulsh a b result) - (if (<= (ash (&max/u64 a) (&max/u64 b)) &u64-max) + (if (and + (or (zero? (&max/u64 a)) (< (&max/u64 b) 64)) ; don't even try + (<= (ash (&max/u64 a) (&max/u64 b)) &u64-max)) ;; No overflow; we can be precise. (define! result &u64 (ash (&min/0 a) (&min/0 b)) -- 2.33.1