diff --git a/source/slang/slang-check-constraint.cpp b/source/slang/slang-check-constraint.cpp
index 90b0e44f52..b213653387 100644
--- a/source/slang/slang-check-constraint.cpp
+++ b/source/slang/slang-check-constraint.cpp
@@ -779,8 +779,8 @@ namespace Slang
                 SLANG_ASSERT(constraintDecl2);
                 return TryUnifyTypes(constraints,
                     unifyCtx,
-                    constraintDecl1.getDecl()->getSup().type,
-                    constraintDecl2.getDecl()->getSup().type);
+                    getSup(m_astBuilder, constraintDecl1),
+                    getSup(m_astBuilder, constraintDecl2));
             }
         }
 
diff --git a/tests/language-feature/generics/nested-gen-value-param-inference-2.slang b/tests/language-feature/generics/nested-gen-value-param-inference-2.slang
new file mode 100644
index 0000000000..038329e878
--- /dev/null
+++ b/tests/language-feature/generics/nested-gen-value-param-inference-2.slang
@@ -0,0 +1,41 @@
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=CHECK):-slang -compute -shaderobj -output-using-type
+//TEST(compute, vulkan):COMPARE_COMPUTE_EX(filecheck-buffer=CHECK):-vk -compute -shaderobj -output-using-type
+
+interface IValueGeneric<let D : int> {}
+struct ValGenericImpl<let D : int> : IValueGeneric<D> {}
+
+struct NestedValueGeneric<let D : int, S : IValueGeneric<D>>
+{
+    int x;
+}
+
+void acceptor<let D : int, S : IValueGeneric<D>>(NestedValueGeneric<D, S> x)
+{
+    outputBuffer[0] = D + x.x;
+}
+
+extension<let D : int, S : IValueGeneric<D>> NestedValueGeneric<D, S>
+{
+    void foo()
+    {
+        acceptor(this);
+    }
+}
+void test2(NestedValueGeneric<2, ValGenericImpl<2>> x)
+{
+    // 'foo' should be a member of 'NestedValueGeneric<2, ValGenericImpl<2>>' through
+    // the extension above.
+    x.foo();
+}
+
+//TEST_INPUT:ubuffer(data=[0 0 0 0], stride=4):out,name=outputBuffer
+RWStructuredBuffer<int> outputBuffer;
+
+[numthreads(1, 1, 1)]
+void computeMain(int3 dispatchThreadID: SV_DispatchThreadID)
+{
+    NestedValueGeneric<2, ValGenericImpl<2>> x;
+    x.x = 1;
+    test2(x);
+    // CHECK: 3
+}
\ No newline at end of file
diff --git a/tests/language-feature/generics/nested-gen-value-param-inference.slang b/tests/language-feature/generics/nested-gen-value-param-inference.slang
new file mode 100644
index 0000000000..cf7e5faf8d
--- /dev/null
+++ b/tests/language-feature/generics/nested-gen-value-param-inference.slang
@@ -0,0 +1,32 @@
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=CHECK):-slang -compute -shaderobj -output-using-type
+//TEST(compute, vulkan):COMPARE_COMPUTE_EX(filecheck-buffer=CHECK):-vk -compute -shaderobj -output-using-type
+
+interface IValueGeneric<let D : int> {}
+struct ValGenericImpl<let D : int> : IValueGeneric<D> {}
+
+struct NestedValueGeneric<let D : int, S : IValueGeneric<D>>
+{
+    int x;
+}
+
+void acceptor<let D : int, S : IValueGeneric<D>>(NestedValueGeneric<D, S> x)
+{
+    outputBuffer[0] = D + x.x;
+}
+void test(NestedValueGeneric<2, ValGenericImpl<2>> x)
+{
+    // Test that we can correctly infer acceptor.D and acceptor.S from `x`.
+    acceptor(x);
+}
+
+//TEST_INPUT:ubuffer(data=[0 0 0 0], stride=4):out,name=outputBuffer
+RWStructuredBuffer<int> outputBuffer;
+
+[numthreads(1, 1, 1)]
+void computeMain(int3 dispatchThreadID: SV_DispatchThreadID)
+{
+    NestedValueGeneric<2, ValGenericImpl<2>> x;
+    x.x = 1;
+    test(x);
+    // CHECK: 3
+}
\ No newline at end of file