From 668a42e71a92c51f27e99a1974ae4890fe98cea3 Mon Sep 17 00:00:00 2001
From: biondizzle <biondizzle@gmail.com>
Date: Tue, 2 Jun 2026 04:02:34 +0000
Subject: [PATCH] debug: print mhc_sinkhorn CUDA kernel compile errors

---
 dsv4/layers/mhc.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/dsv4/layers/mhc.py b/dsv4/layers/mhc.py
index 88486589..eb95a2a9 100644
--- a/dsv4/layers/mhc.py
+++ b/dsv4/layers/mhc.py
@@ -99,7 +99,8 @@ def sinkhorn_knopp(
         from dsv4.kernels.cuda.loader import get_cuda_module
         mod = get_cuda_module("mhc_sinkhorn", ["mhc_sinkhorn.cu"])
         return mod.mhc_sinkhorn(logits.float(), t_max, eps)
-    except Exception:
+    except Exception as e:
+        import sys; print(f"mhc_sinkhorn CUDA kernel failed: {e}, falling back to Python", file=sys.stderr, flush=True)
         pass  # Fall back to Python
     
     # Python fallback