diff --git a/compiler/fir/resolve/testData/resolve/stdlib/problems/complexSmartCasts.kt b/compiler/fir/resolve/testData/resolve/stdlib/problems/complexSmartCasts.kt
new file mode 100644
index 00000000000..165543e7a17
--- /dev/null
+++ b/compiler/fir/resolve/testData/resolve/stdlib/problems/complexSmartCasts.kt
@@ -0,0 +1,57 @@
+fun <T> runHigherOrder(f: () -> T): T = f()
+
+val String.ext: Int get() = length
+
+fun foo(a: Any?) {
+    val s = a as? String
+    val length = s?.ext ?: return
+    runHigherOrder {
+        s.isNotEmpty()
+    }
+}
+
+fun bar(s: String?) {
+    if (s?.isNotEmpty() == true) {
+        s.<!INAPPLICABLE_CANDIDATE!>length<!>
+    }
+}
+
+fun baz(s: String?) {
+    when {
+        !s.isNullOrEmpty() -> s.<!INAPPLICABLE_CANDIDATE!>length<!>
+    }
+}
+
+fun bazz(s: String?) {
+    s?.let { use(it) }
+}
+
+class Wrapper(val s: String?) {
+    fun withThis() {
+        if (s != null) {
+            use(this.s)
+        }
+        if (this.s != null) {
+            use(s)
+        }
+    }
+}
+
+fun Any.withInvoke(f: String.() -> Unit) {
+    if (this is String) {
+        <!INAPPLICABLE_CANDIDATE!>f<!>()
+    }
+}
+
+fun String.withInvoke(f: String.() -> Unit) {
+    f()
+}
+
+fun <X> withBangBang(a: X) {
+    if (a is String?) {
+        <!INAPPLICABLE_CANDIDATE!>use<!>(a!!)
+    }
+}
+
+fun use(s: String) {}
+
diff --git a/compiler/fir/resolve/testData/resolve/stdlib/problems/complexSmartCasts.txt b/compiler/fir/resolve/testData/resolve/stdlib/problems/complexSmartCasts.txt
new file mode 100644
index 00000000000..f041a578478
--- /dev/null
+++ b/compiler/fir/resolve/testData/resolve/stdlib/problems/complexSmartCasts.txt
@@ -0,0 +1,91 @@
+FILE: complexSmartCasts.kt
+    public final fun <T> runHigherOrder(f: R|() -> T|): R|T| {
+        ^runHigherOrder R|<local>/f|.R|FakeOverride<kotlin/Function0.invoke: R|T|>|()
+    }
+    public final val R|kotlin/String|.ext: R|kotlin/Int|
+        public get(): R|kotlin/Int| {
+            ^ this@R|/ext|.R|kotlin/String.length|
+        }
+    public final fun foo(a: R|kotlin/Any?|): R|kotlin/Unit| {
+        lval s: R|kotlin/String?| = (R|<local>/a| as? R|kotlin/String|)
+        lval length: R|kotlin/Int| = when (lval <elvis>: R|kotlin/Int?| = R|<local>/s|?.R|/ext|) {
+            ==($subj$, Null(null)) ->  {
+                ^foo Unit
+            }
+            else ->  {
+                R|<local>/<elvis>|
+            }
+        }
+
+        R|/runHigherOrder|<R|kotlin/Boolean|>(<L> = runHigherOrder@fun <anonymous>(): R|kotlin/Boolean| {
+            R|<local>/s|.R|kotlin/text/isNotEmpty|()
+        }
+        )
+    }
+    public final fun bar(s: R|kotlin/String?|): R|kotlin/Unit| {
+        when () {
+            ==(R|<local>/s|?.R|kotlin/text/isNotEmpty|(), Boolean(true)) ->  {
+                R|<local>/s|.<Inapplicable(WRONG_RECEIVER): [kotlin/String.length]>#
+            }
+        }
+
+    }
+    public final fun baz(s: R|kotlin/String?|): R|kotlin/Unit| {
+        when () {
+            R|<local>/s|.R|kotlin/text/isNullOrEmpty|().R|kotlin/Boolean.not|() ->  {
+                R|<local>/s|.<Inapplicable(WRONG_RECEIVER): [kotlin/String.length]>#
+            }
+        }
+
+    }
+    public final fun bazz(s: R|kotlin/String?|): R|kotlin/Unit| {
+        R|<local>/s|?.R|kotlin/let|<R|kotlin/String|, R|kotlin/Unit|>(<L> = let@fun <anonymous>(it: R|kotlin/String|): R|kotlin/Unit| <kind=EXACTLY_ONCE>  {
+            R|/use|(R|<local>/it|)
+        }
+        )
+    }
+    public final class Wrapper : R|kotlin/Any| {
+        public constructor(s: R|kotlin/String?|): R|Wrapper| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final val s: R|kotlin/String?| = R|<local>/s|
+            public get(): R|kotlin/String?|
+
+        public final fun withThis(): R|kotlin/Unit| {
+            when () {
+                !=(this@R|/Wrapper|.R|/Wrapper.s|, Null(null)) ->  {
+                    R|/use|(this@R|/Wrapper|.R|/Wrapper.s|)
+                }
+            }
+
+            when () {
+                !=(this@R|/Wrapper|.R|/Wrapper.s|, Null(null)) ->  {
+                    R|/use|(this@R|/Wrapper|.R|/Wrapper.s|)
+                }
+            }
+
+        }
+
+    }
+    public final fun R|kotlin/Any|.withInvoke(f: R|kotlin/String.() -> kotlin/Unit|): R|kotlin/Unit| {
+        when () {
+            (this@R|/withInvoke| is R|kotlin/String|) ->  {
+                <Inapplicable(INAPPLICABLE): [kotlin/Function1.invoke]>#()
+            }
+        }
+
+    }
+    public final fun R|kotlin/String|.withInvoke(f: R|kotlin/String.() -> kotlin/Unit|): R|kotlin/Unit| {
+        R|<local>/f|.R|FakeOverride<kotlin/Function1.invoke: R|kotlin/Unit|>|(this@R|/withInvoke|)
+    }
+    public final fun <X> withBangBang(a: R|X|): R|kotlin/Unit| {
+        when () {
+            (R|<local>/a| is R|kotlin/String?|) ->  {
+                <Inapplicable(INAPPLICABLE): [/use]>#(R|<local>/a|!!)
+            }
+        }
+
+    }
+    public final fun use(s: R|kotlin/String|): R|kotlin/Unit| {
+    }
diff --git a/compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirDiagnosticsWithStdlibTestGenerated.java b/compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirDiagnosticsWithStdlibTestGenerated.java
index f13578b9a2e..d7c07944881 100644
--- a/compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirDiagnosticsWithStdlibTestGenerated.java
+++ b/compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirDiagnosticsWithStdlibTestGenerated.java
@@ -627,6 +627,11 @@ public class FirDiagnosticsWithStdlibTestGenerated extends AbstractFirDiagnostic
             runTest("compiler/fir/resolve/testData/resolve/stdlib/problems/cloneArray.kt");
         }
 
+        @TestMetadata("complexSmartCasts.kt")
+        public void testComplexSmartCasts() throws Exception {
+            runTest("compiler/fir/resolve/testData/resolve/stdlib/problems/complexSmartCasts.kt");
+        }
+
         @TestMetadata("delegateTypeMismatch.kt")
         public void testDelegateTypeMismatch() throws Exception {
             runTest("compiler/fir/resolve/testData/resolve/stdlib/problems/delegateTypeMismatch.kt");