diff --git a/pyproject.toml b/pyproject.toml
index 408cd00bf..4e0964295 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,3 +1,9 @@
 [build-system]
 requires = ["setuptools", "wheel", "pybind11~=2.11.1"]
 build-backend = "setuptools.build_meta"
+
+[tool.cibuildwheel.windows.environment]
+# CAUTION! This is /Od instead of /O2 because of bugs in the msvc compiler!
+# See: https://github.com/quantumlib/Stim/issues/1078
+CFLAGS = "/Od"
+CXXFLAGS = "/Od"
diff --git a/setup.py b/setup.py
index a310d368f..8305e8359 100644
--- a/setup.py
+++ b/setup.py
@@ -30,7 +30,9 @@
 if platform.system().startswith('Win'):
     common_compile_args = [
         '/std:c++20',
-        '/O2',
+        # CAUTION! This is /Od instead of /O2 because of bugs in the msvc compiler!
+        # See: https://github.com/quantumlib/Stim/issues/1078
+        '/Od',
         f'/DVERSION_INFO={__version__}',
     ]
     arch_avx = ['/arch:AVX2']