diff --git a/compiler/semexprs.nim b/compiler/semexprs.nim
index 1dc952be51..55a58c7f04 100644
--- a/compiler/semexprs.nim
+++ b/compiler/semexprs.nim
@@ -1787,7 +1787,7 @@ proc propertyWriteAccess(c: PContext, n, nOrig, a: PNode): PNode =
   result = newTreeI(nkCall, n.info, setterId, a[0], n[1])
   result.flags.incl nfDotSetter
   let orig = newTreeI(nkCall, n.info, setterId, aOrig[0], nOrig[1])
-  result = semOverloadedCallAnalyseEffects(c, result, orig, {})
+  result = semOverloadedCallAnalyseEffects(c, result, orig, {efNoUndeclared})
 
   if result != nil:
     result = afterCallActions(c, result, nOrig, {})
diff --git a/tests/specialops/terrmsgs.nim b/tests/specialops/terrmsgs.nim
index 081bca4510..534c0c4543 100644
--- a/tests/specialops/terrmsgs.nim
+++ b/tests/specialops/terrmsgs.nim
@@ -26,8 +26,7 @@ block:
   block:
     template `.=`(a: Foo, b: untyped, c: untyped) = b = c
     b.x = 123 #[tt.Error
-        ^ undeclared field: 'x=' for type terrmsgs.Bar [type declared in terrmsgs.nim(15, 8)]]#
-    # yeah it says x= but does it matter in practice
+     ^ undeclared field: 'x' for type terrmsgs.Bar [type declared in terrmsgs.nim(15, 8)]]#
   block:
     template `()`(a: Foo, b: untyped, c: untyped) = echo "something"
 
diff --git a/tests/specialops/tmismatch.nim b/tests/specialops/tmismatch.nim
index 76c921b14a..7d0a4229dc 100644
--- a/tests/specialops/tmismatch.nim
+++ b/tests/specialops/tmismatch.nim
@@ -14,4 +14,4 @@ template `.=`*(flags: Flags, key: Flag, val: bool) =
 var flags: Flags
 
 flags.A = 123 #[tt.Error
-        ^ undeclared field: 'A=' for type tmismatch.Flags [type declared in tmismatch.nim(9, 5)]]#
+     ^ undeclared field: 'A' for type tmismatch.Flags [type declared in tmismatch.nim(9, 5)]]#
diff --git a/tests/specialops/tsetterfallback1.nim b/tests/specialops/tsetterfallback1.nim
new file mode 100644
index 0000000000..6a0b1104e3
--- /dev/null
+++ b/tests/specialops/tsetterfallback1.nim
@@ -0,0 +1,24 @@
+# issue #4711
+
+type
+  Vec4 = object
+    x,y,z,w : float32
+
+  Vec3 = object
+    x,y,z : float32
+
+proc `+=`(v0: var Vec3; v1: Vec3) =
+  v0.x += v1.x
+  v0.y += v1.y
+  v0.z += v1.z
+
+proc xyz(v: var Vec4): var Vec3 =
+  cast[ptr Vec3](v.x.addr)[]
+
+let tmp = Vec3(x: 1, y:2, z:3)
+var dst = Vec4(x: 4, y:4, z:4, w:4)
+
+xyz(dst)  = tmp # works
+dst.xyz() = tmp # works
+dst.xyz  += tmp # works
+dst.xyz   = tmp # attempting to call undeclared routine `xyz=`
diff --git a/tests/specialops/tsetterfallback2.nim b/tests/specialops/tsetterfallback2.nim
new file mode 100644
index 0000000000..8458b2dc8b
--- /dev/null
+++ b/tests/specialops/tsetterfallback2.nim
@@ -0,0 +1,8 @@
+# https://forum.nim-lang.org/t/12785
+
+proc x(pt: var array[2, float]): var float = pt[0]
+
+var pt = [0.0, 0.0]
+pt.x += 1.0 # <-- fine
+x(pt) = 1.0 # <-- fine
+pt.x = 1.0 # <-- does not compile