diff --git a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
index 9cab87d18b8..69f0cf57e02 100644
--- a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
+++ b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
@@ -17825,6 +17825,30 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
           runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareType.kt");
         }
 
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeAs.kt")
+        public void testLambdaParameterForBareTypeAs() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt")
+        public void testLambdaParameterForBareTypeEarlyFixationAffectsBehavior() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeOnOuterTypeVariable.kt")
+        public void testLambdaParameterForBareTypeOnOuterTypeVariable() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForNonBareType.kt")
+        public void testLambdaParameterForNonBareType() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.kt");
+        }
+
         @Test
         @TestMetadata("lambdaParameterTypeFixation.kt")
         public void testLambdaParameterTypeFixation() {
diff --git a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
index 645cd388eef..43485bf3c32 100644
--- a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
+++ b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
@@ -17825,6 +17825,30 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
           runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareType.kt");
         }
 
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeAs.kt")
+        public void testLambdaParameterForBareTypeAs() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt")
+        public void testLambdaParameterForBareTypeEarlyFixationAffectsBehavior() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeOnOuterTypeVariable.kt")
+        public void testLambdaParameterForBareTypeOnOuterTypeVariable() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForNonBareType.kt")
+        public void testLambdaParameterForNonBareType() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.kt");
+        }
+
         @Test
         @TestMetadata("lambdaParameterTypeFixation.kt")
         public void testLambdaParameterTypeFixation() {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java
index 4fc2ef7813e..986bc7baea9 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java
@@ -17819,6 +17819,30 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
           runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareType.kt");
         }
 
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeAs.kt")
+        public void testLambdaParameterForBareTypeAs() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt")
+        public void testLambdaParameterForBareTypeEarlyFixationAffectsBehavior() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeOnOuterTypeVariable.kt")
+        public void testLambdaParameterForBareTypeOnOuterTypeVariable() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForNonBareType.kt")
+        public void testLambdaParameterForNonBareType() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.kt");
+        }
+
         @Test
         @TestMetadata("lambdaParameterTypeFixation.kt")
         public void testLambdaParameterTypeFixation() {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java
index 4e5e27e9148..f70c15e6448 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java
@@ -17825,6 +17825,30 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
           runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareType.kt");
         }
 
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeAs.kt")
+        public void testLambdaParameterForBareTypeAs() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt")
+        public void testLambdaParameterForBareTypeEarlyFixationAffectsBehavior() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeOnOuterTypeVariable.kt")
+        public void testLambdaParameterForBareTypeOnOuterTypeVariable() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForNonBareType.kt")
+        public void testLambdaParameterForNonBareType() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.kt");
+        }
+
         @Test
         @TestMetadata("lambdaParameterTypeFixation.kt")
         public void testLambdaParameterTypeFixation() {
diff --git a/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.fir.kt b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.fir.kt
new file mode 100644
index 00000000000..ffd5d68faac
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.fir.kt
@@ -0,0 +1,28 @@
+// ISSUE: KT-64840
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface A<F> {
+    val a: F
+}
+
+interface B<G> : A<G> {
+    val b: G
+}
+
+fun <X> withCallback(x: X, c: Controller<in X>, p: (X) -> Unit) {}
+
+fun main(a: A<String>) {
+    val x = generate {
+        withCallback(a, this) {
+            (it as <!NO_TYPE_ARGUMENTS_ON_RHS!>B<!>).<!UNRESOLVED_REFERENCE!>b<!>.length
+            it.<!UNRESOLVED_REFERENCE!>b<!>.length
+            it.a.length
+        }
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("A<kotlin.String>")!>x<!>
+}
diff --git a/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.kt b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.kt
new file mode 100644
index 00000000000..7ea3c3e6bef
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.kt
@@ -0,0 +1,28 @@
+// ISSUE: KT-64840
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface A<F> {
+    val a: F
+}
+
+interface B<G> : A<G> {
+    val b: G
+}
+
+fun <X> withCallback(x: X, c: Controller<in X>, p: (X) -> Unit) {}
+
+fun main(a: A<String>) {
+    val x = generate {
+        withCallback(a, this) {
+            (it as B).b.length
+            <!DEBUG_INFO_SMARTCAST!>it<!>.b.length
+            it.a.length
+        }
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("A<kotlin.String>")!>x<!>
+}
diff --git a/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.fir.kt b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.fir.kt
new file mode 100644
index 00000000000..9bd5e18ba56
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.fir.kt
@@ -0,0 +1,37 @@
+// !CHECK_TYPE
+// ISSUE: KT-64840
+
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface CommonSupertype
+interface A<F> : CommonSupertype
+interface B<G> : A<G>
+interface C : CommonSupertype
+
+fun <X> predicate(x: X, c: Controller<X>, p: (X) -> Unit) {}
+
+fun main(a: A<*>, c: C) {
+    val x1 = generate {
+        predicate(a, this) { x ->
+            // x is B
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x1<!>
+
+    val x2 = generate {
+        predicate(a, this) { x ->
+            x is <!NO_TYPE_ARGUMENTS_ON_RHS!>B<!>
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x2<!>
+}
diff --git a/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt
new file mode 100644
index 00000000000..ca13fa480da
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt
@@ -0,0 +1,37 @@
+// !CHECK_TYPE
+// ISSUE: KT-64840
+
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface CommonSupertype
+interface A<F> : CommonSupertype
+interface B<G> : A<G>
+interface C : CommonSupertype
+
+fun <X> predicate(x: X, c: Controller<X>, p: (X) -> Unit) {}
+
+fun main(a: A<*>, c: C) {
+    val x1 = generate {
+        predicate(a, this) { x ->
+            // x is B
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x1<!>
+
+    val x2 = generate {
+        predicate(a, this) { x ->
+            <!USELESS_IS_CHECK!>x is <!NO_TYPE_ARGUMENTS_ON_RHS!>B<!><!>
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x2<!>
+}
diff --git a/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.fir.kt b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.fir.kt
new file mode 100644
index 00000000000..ccbbbf3ac3e
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.fir.kt
@@ -0,0 +1,20 @@
+// ISSUE: KT-64840
+class Controller<T> {
+    val t: T get() = TODO()
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface A<F> {
+    val a: F?
+}
+
+interface B<G> : A<G>
+
+fun main(a: A<*>) {
+    generate {
+        yield(a)
+        t is <!NO_TYPE_ARGUMENTS_ON_RHS!>B<!>
+    }.a
+}
diff --git a/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.kt b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.kt
new file mode 100644
index 00000000000..9160820606d
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.kt
@@ -0,0 +1,20 @@
+// ISSUE: KT-64840
+class Controller<T> {
+    val t: T get() = TODO()
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface A<F> {
+    val a: F?
+}
+
+interface B<G> : A<G>
+
+fun main(a: A<*>) {
+    generate {
+        yield(a)
+        <!USELESS_IS_CHECK!>t is <!NO_TYPE_ARGUMENTS_ON_RHS!>B<!><!>
+    }.a
+}
diff --git a/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.fir.kt b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.fir.kt
new file mode 100644
index 00000000000..4fe24c08f04
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.fir.kt
@@ -0,0 +1,27 @@
+// ISSUE: KT-64840
+
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface CommonSupertype
+interface A<F> : CommonSupertype
+interface B : A<String>
+interface C : CommonSupertype
+
+fun <X> predicate(x: X, c: Controller<X>, p: (X) -> Boolean) {}
+
+fun main(a: A<String>, c: C) {
+    val x2 = generate {
+        predicate(a, this) { x ->
+            // USELESS_IS_CHECK is errorenously reported in K1
+            x is B
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x2<!>
+}
diff --git a/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.kt b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.kt
new file mode 100644
index 00000000000..1f2c5582c21
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.kt
@@ -0,0 +1,27 @@
+// ISSUE: KT-64840
+
+class Controller<T> {
+    fun yield(t: T): Boolean = true
+}
+
+fun <S> generate(g: suspend Controller<S>.() -> Unit): S = TODO()
+
+interface CommonSupertype
+interface A<F> : CommonSupertype
+interface B : A<String>
+interface C : CommonSupertype
+
+fun <X> predicate(x: X, c: Controller<X>, p: (X) -> Boolean) {}
+
+fun main(a: A<String>, c: C) {
+    val x2 = generate {
+        predicate(a, this) { x ->
+            // USELESS_IS_CHECK is errorenously reported in K1
+            <!USELESS_IS_CHECK!>x is B<!>
+        }
+
+        yield(c)
+    }
+
+    <!DEBUG_INFO_EXPRESSION_TYPE("CommonSupertype")!>x2<!>
+}
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
index 2073f3b6194..39c3a850220 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
@@ -17825,6 +17825,30 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
           runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareType.kt");
         }
 
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeAs.kt")
+        public void testLambdaParameterForBareTypeAs() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeAs.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt")
+        public void testLambdaParameterForBareTypeEarlyFixationAffectsBehavior() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeEarlyFixationAffectsBehavior.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForBareTypeOnOuterTypeVariable.kt")
+        public void testLambdaParameterForBareTypeOnOuterTypeVariable() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForBareTypeOnOuterTypeVariable.kt");
+        }
+
+        @Test
+        @TestMetadata("lambdaParameterForNonBareType.kt")
+        public void testLambdaParameterForNonBareType() {
+          runTest("compiler/testData/diagnostics/tests/inference/builderInference/lambdaParameterForNonBareType.kt");
+        }
+
         @Test
         @TestMetadata("lambdaParameterTypeFixation.kt")
         public void testLambdaParameterTypeFixation() {