5 files changed, 39 insertions, 5 deletions
diff --git a/tests/autodiff/getter-setter.slang b/tests/autodiff/getter-setter.slang
index 705604bbb..06caadce8 100644
--- a/tests/autodiff/getter-setter.slang
+++ b/tests/autodiff/getter-setter.slang
@@ -45,7 +45,7 @@ typedef DifferentialPair<A> dpA;
 A f(A a)
 {
     A aout;
-    aout.y = 2 * a.x;
+    aout.y = detach(2 * a.x);
     aout.x = 5 * a.x;
 
     return aout;
diff --git a/tests/autodiff/reverse-inout-param-2.slang b/tests/autodiff/reverse-inout-param-2.slang
index 18eb825e6..813238863 100644
--- a/tests/autodiff/reverse-inout-param-2.slang
+++ b/tests/autodiff/reverse-inout-param-2.slang
@@ -28,7 +28,7 @@ void g(
     v1 = v2;
     v2.nd = v2.nd + 1.0;
     p.n = v1.nd + 1.0;
-    p.m = v2.nd + 1.0 + x; // == v2.nd + 2 + x == 1 + 2 + x == 3+x
+    p.m = detach(v2.nd + 1.0 + x); // == v2.nd + 2 + x == 1 + 2 + x == 3+x
     po = p;
     po.m += 1.0; // == 4+x
     y = p.m * x; // == (3+x)*x
@@ -39,7 +39,7 @@ void f(inout no_diff D p, out no_diff D p0, out ND v1, inout ND v2, float x, out
 {
     // v2.nd is 3.
     g(p, p0, v1, v2, x, y);
-    // v2.nd is now 4, now g is equivalent to (4+x)*x.
+    // v2.nd is now 4, now g is equivalent to detach(4+x)*x, so g' = 9.
     g(p, p0, v1, v2, x, y);
 }
 
@@ -64,7 +64,7 @@ void computeMain(uint3 dispatchThreadID : SV_DispatchThreadID)
     __bwd_diff(f)(p, v2, x, yDiffOut);
 
     outputBuffer[0] = x.p; // should be 5, since bwd_diff does not write back new primal val.
-    outputBuffer[1] = x.d; // 14
+    outputBuffer[1] = x.d; // 9
     outputBuffer[2] = p.m; // 1.0
     outputBuffer[3] = p.n; // 2.0
     outputBuffer[4] = v2.nd; // 1.0
diff --git a/tests/autodiff/reverse-inout-param-2.slang.expected.txt b/tests/autodiff/reverse-inout-param-2.slang.expected.txt
index 65933cc7d..492ad8d10 100644
--- a/tests/autodiff/reverse-inout-param-2.slang.expected.txt
+++ b/tests/autodiff/reverse-inout-param-2.slang.expected.txt
@@ -1,6 +1,6 @@
 type: float
 5.000000
-14.000000
+9.000000
 1.000000
 2.000000
 1.000000
diff --git a/tests/diagnostics/autodiff-data-flow-3.slang b/tests/diagnostics/autodiff-data-flow-3.slang
new file mode 100644
index 000000000..0a8e3e58a
--- /dev/null
+++ b/tests/diagnostics/autodiff-data-flow-3.slang
@@ -0,0 +1,26 @@
+//DIAGNOSTIC_TEST:SIMPLE:
+
+struct DiffT : IDifferentiable
+{
+    float f;
+}
+struct NoDiffField
+{
+    DiffT fp;
+}
+
+[BackwardDifferentiable]
+float g(float x)
+{
+    NoDiffField obj;
+    obj.fp.f = x * x; // Error, this location cannot hold derivative.
+    return obj.fp.f;
+}
+
+[BackwardDifferentiable]
+float h(float x)
+{
+    NoDiffField obj;
+    obj.fp.f = detach(x * x); // OK.
+    return obj.fp.f;
+}
diff --git a/tests/diagnostics/autodiff-data-flow-3.slang.expected b/tests/diagnostics/autodiff-data-flow-3.slang.expected
new file mode 100644
index 000000000..73381cf58
--- /dev/null
+++ b/tests/diagnostics/autodiff-data-flow-3.slang.expected
@@ -0,0 +1,8 @@
+result code = -1
+standard error = {
+tests/diagnostics/autodiff-data-flow-3.slang(16): error 41024: derivative is lost during assignment to non-differentiable location. Use 'detach()' to clarify intention.
+    obj.fp.f = x * x; // Error, this location cannot hold derivative.
+             ^
+}
+standard output = {
+}