diff --git a/build-constraints.yaml b/build-constraints.yaml
index 1384524a..f21f679f 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -8428,7 +8428,7 @@ expected-test-failures:
     # these if we want them fixed
     - domain-optics # `demo`: executable not found
     - ghci-hexcalc # https://github.com/takenobu-hs/ghci-hexcalc/issues/2
-    - isocline # segfault https://github.com/daanx/isocline/issues/1
+    - isocline # hung with ghc-9.12.4 RC1
     - rounded # segfault
     - shake-language-c # Cannot reproduce locally, looks like it may be a bug in Stack or curator
     - skein # openfile: does not exist https://github.com/fpco/stackage/issues/1187