From 77db8396d09864111343dd13bdf5c42a251556fe Mon Sep 17 00:00:00 2001
From: Laurent Mazare <laurent.mazare@gmail.com>
Date: Wed, 22 Jan 2025 21:31:49 +0100
Subject: [PATCH] Explicit error when slice-set is called with the same src and
 dst. (#2733)

---
 candle-core/src/tensor_cat.rs     | 3 +++
 candle-core/tests/tensor_tests.rs | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/candle-core/src/tensor_cat.rs b/candle-core/src/tensor_cat.rs
index be6dfe61..20b805c7 100644
--- a/candle-core/src/tensor_cat.rs
+++ b/candle-core/src/tensor_cat.rs
@@ -248,6 +248,9 @@ impl Tensor {
         if !self.is_contiguous() || !src.is_contiguous() {
             Err(Error::RequiresContiguous { op: "slice-set" }.bt())?
         }
+        if self.same_storage(src) {
+            crate::bail!("cannot use slice_set when self and src share their storage")
+        }
         if self.dtype() != src.dtype() {
             Err(Error::DTypeMismatchBinaryOp {
                 lhs: self.dtype(),
diff --git a/candle-core/tests/tensor_tests.rs b/candle-core/tests/tensor_tests.rs
index e3246a33..17238dcd 100644
--- a/candle-core/tests/tensor_tests.rs
+++ b/candle-core/tests/tensor_tests.rs
@@ -729,6 +729,8 @@ fn slice_set(device: &Device) -> Result<()> {
         .sum_all()?
         .to_vec0::<f32>()?;
     assert_eq!(diff, 0.);
+    // This used to create a deadlock rather than returning an actual error.
+    assert!(cache.slice_set(&cache, 0, 0).is_err());
     Ok(())
 }