From b426fc5d4c7dad43e6970eede68e0d84eb61b9d9 Mon Sep 17 00:00:00 2001
From: Matt Witherspoon <32485495+spoonincode@users.noreply.github.com>
Date: Thu, 7 Mar 2024 22:56:44 -0500
Subject: [PATCH] don't use BitInt when UBSAN is enabled

---
 src/CMakeLists.txt | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 8c2cfac..3bf8710 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -1,6 +1,12 @@
 include(CheckCXXSourceCompiles)
 
 check_cxx_source_compiles("
+#if defined(__has_feature)
+#  if __has_feature(undefined_behavior_sanitizer)
+#    error UBSAN and bitint don't work together yet, see https://github.com/llvm/llvm-project/issues/64100
+#  endif
+#endif
+
 int main() {
   using T=_ExtInt(512);
   return 0;