3 files changed, 14 insertions, 0 deletions
diff --git a/testsuite/tests/typecheck/should_fail/T17284.hs b/testsuite/tests/typecheck/should_fail/T17284.hs
new file mode 100644
index 0000000000..d32dce2ba0
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T17284.hs
@@ -0,0 +1,9 @@
+{-# LANGUAGE MonomorphismRestriction #-}
+{-# LANGUAGE PartialTypeSignatures #-}
+
+module MonoPoly where
+
+f :: Num a => a -> _
+f x = x + y
+
+y = f 1
diff --git a/testsuite/tests/typecheck/should_fail/T17284.stderr b/testsuite/tests/typecheck/should_fail/T17284.stderr
new file mode 100644
index 0000000000..992f147089
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T17284.stderr
@@ -0,0 +1,4 @@
+
+T17284.hs:6:1: error: [GHC-16675]
+    Overloaded signature conflicts with monomorphism restriction
+      [partial signature] f :: Num a => a -> _
diff --git a/testsuite/tests/typecheck/should_fail/all.T b/testsuite/tests/typecheck/should_fail/all.T
index f13dd45b08..f62ee5e355 100644
--- a/testsuite/tests/typecheck/should_fail/all.T
+++ b/testsuite/tests/typecheck/should_fail/all.T
@@ -681,3 +681,4 @@ test('LazyFieldsDisabled', normal, compile_fail, [''])
 test('TyfamsDisabled', normal, compile_fail, [''])
 test('CommonFieldResultTypeMismatch', normal, compile_fail, [''])
 test('CommonFieldTypeMismatch', normal, compile_fail, [''])
+test('T17284', normal, compile_fail, [''])