diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsCompiledJavaTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsCompiledJavaTestGenerated.java
index 3ab4739fe63..6c6ffac2af6 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsCompiledJavaTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsCompiledJavaTestGenerated.java
@@ -925,6 +925,12 @@ public class FirOldFrontendForeignAnnotationsCompiledJavaTestGenerated extends A
                 runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48261.kt");
             }
 
+            @Test
+            @TestMetadata("kt48778.kt")
+            public void testKt48778() throws Exception {
+                runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.kt");
+            }
+
             @Test
             @TestMetadata("methodWithTypeParameter.kt")
             public void testMethodWithTypeParameter() throws Exception {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsCompiledJavaWithPsiClassReadingTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsCompiledJavaWithPsiClassReadingTestGenerated.java
index 3c4ab38c7e0..f4bde3a6554 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsCompiledJavaWithPsiClassReadingTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsCompiledJavaWithPsiClassReadingTestGenerated.java
@@ -925,6 +925,12 @@ public class FirOldFrontendForeignAnnotationsCompiledJavaWithPsiClassReadingTest
                 runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48261.kt");
             }
 
+            @Test
+            @TestMetadata("kt48778.kt")
+            public void testKt48778() throws Exception {
+                runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.kt");
+            }
+
             @Test
             @TestMetadata("methodWithTypeParameter.kt")
             public void testMethodWithTypeParameter() throws Exception {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsSourceJavaTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsSourceJavaTestGenerated.java
index 82530bc5020..a008a340a76 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsSourceJavaTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendForeignAnnotationsSourceJavaTestGenerated.java
@@ -925,6 +925,12 @@ public class FirOldFrontendForeignAnnotationsSourceJavaTestGenerated extends Abs
                 runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48261.kt");
             }
 
+            @Test
+            @TestMetadata("kt48778.kt")
+            public void testKt48778() throws Exception {
+                runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.kt");
+            }
+
             @Test
             @TestMetadata("methodWithTypeParameter.kt")
             public void testMethodWithTypeParameter() throws Exception {
diff --git a/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/NewTypeSubstitutor.kt b/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/NewTypeSubstitutor.kt
index 3bab1500451..fb65eaaacc0 100644
--- a/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/NewTypeSubstitutor.kt
+++ b/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/NewTypeSubstitutor.kt
@@ -9,6 +9,7 @@ import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
 import org.jetbrains.kotlin.descriptors.annotations.CompositeAnnotations
 import org.jetbrains.kotlin.resolve.calls.inference.isCaptured
 import org.jetbrains.kotlin.resolve.calls.inference.model.TypeVariableFromCallableDescriptor
+import org.jetbrains.kotlin.resolve.calls.inference.model.TypeVariableTypeConstructor
 import org.jetbrains.kotlin.resolve.calls.inference.substitute
 import org.jetbrains.kotlin.types.*
 import org.jetbrains.kotlin.types.checker.NewCapturedType
@@ -157,7 +158,11 @@ interface NewTypeSubstitutor : TypeSubstitutorMarker {
             replacement = replacement.makeDefinitelyNotNullOrNotNull()
         }
         if (type is CustomTypeParameter) {
-            replacement = type.substitutionResult(replacement).unwrap()
+            replacement = type.substitutionResult(replacement).unwrap().run {
+                if (type is NotNullTypeVariable && replacement.constructor is TypeVariableTypeConstructor) {
+                    makeDefinitelyNotNullOrNotNull()
+                } else this
+            }
         }
 
         return replacement
diff --git a/compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/jspecify/warnMode/TypeParameterBounds.kt b/compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/jspecify/warnMode/TypeParameterBounds.kt
index c2aa20fbe18..c56d8c881c4 100644
--- a/compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/jspecify/warnMode/TypeParameterBounds.kt
+++ b/compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/jspecify/warnMode/TypeParameterBounds.kt
@@ -23,24 +23,24 @@ public class Test {}
 // jspecify_nullness_mismatch, jspecify_nullness_mismatch
 fun <T : Test> main(a1: A<<!UPPER_BOUND_VIOLATED_BASED_ON_JAVA_ANNOTATIONS!>Any?<!>>, a2: A<Test>, b1: B<<!UPPER_BOUND_VIOLATED_BASED_ON_JAVA_ANNOTATIONS!>Any?<!>>, b2: B<Test>, x: T): Unit {
     a1.foo(null)
-    // jspecify_nullness_mismatch
-    a1.bar<<!UPPER_BOUND_VIOLATED_BASED_ON_JAVA_ANNOTATIONS!>T?<!>>(null)
+    // jspecify_nullness_mismatch, jspecify_nullness_mismatch
+    a1.bar<<!UPPER_BOUND_VIOLATED_BASED_ON_JAVA_ANNOTATIONS!>T?<!>>(<!NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS!>null<!>)
     a1.bar<T>(x)
 
     a2.foo(null)
-    // jspecify_nullness_mismatch
-    a2.bar<<!UPPER_BOUND_VIOLATED_BASED_ON_JAVA_ANNOTATIONS!>T?<!>>(null)
+    // jspecify_nullness_mismatch, jspecify_nullness_mismatch
+    a2.bar<<!UPPER_BOUND_VIOLATED_BASED_ON_JAVA_ANNOTATIONS!>T?<!>>(<!NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS!>null<!>)
     a2.bar<T>(x)
 
     // jspecify_nullness_mismatch
     b1.foo(<!NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS!>null<!>)
-    // jspecify_nullness_mismatch
-    b1.bar<<!UPPER_BOUND_VIOLATED_BASED_ON_JAVA_ANNOTATIONS!>T?<!>>(null)
+    // jspecify_nullness_mismatch, jspecify_nullness_mismatch
+    b1.bar<<!UPPER_BOUND_VIOLATED_BASED_ON_JAVA_ANNOTATIONS!>T?<!>>(<!NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS!>null<!>)
     b1.bar<T>(x)
 
     // jspecify_nullness_mismatch
     b2.foo(<!NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS!>null<!>)
-    // jspecify_nullness_mismatch
-    b2.bar<<!UPPER_BOUND_VIOLATED_BASED_ON_JAVA_ANNOTATIONS!>T?<!>>(null)
+    // jspecify_nullness_mismatch, jspecify_nullness_mismatch
+    b2.bar<<!UPPER_BOUND_VIOLATED_BASED_ON_JAVA_ANNOTATIONS!>T?<!>>(<!NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS!>null<!>)
     b2.bar<T>(x)
 }
diff --git a/compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.kt b/compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.kt
new file mode 100644
index 00000000000..641110863d0
--- /dev/null
+++ b/compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.kt
@@ -0,0 +1,14 @@
+// FIR_IDENTICAL
+// WITH_RUNTIME
+
+// FILE: Java.java
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+public interface Java<T extends @Nullable Object> {
+    @NonNull T getFoo();
+}
+
+// FILE: main.kt
+fun usingMethod(java : Java<String?>) : String = java.getFoo()
+fun usingProperty(java : Java<String?>) : String = java.foo
diff --git a/compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.txt b/compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.txt
new file mode 100644
index 00000000000..2eb59226ee2
--- /dev/null
+++ b/compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.txt
@@ -0,0 +1,11 @@
+package
+
+public fun usingMethod(/*0*/ java: Java<kotlin.String?>): kotlin.String
+public fun usingProperty(/*0*/ java: Java<kotlin.String?>): kotlin.String
+
+public interface Java</*0*/ T> {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    @org.checkerframework.checker.nullness.qual.NonNull public abstract fun getFoo(): @org.checkerframework.checker.nullness.qual.NonNull T
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
diff --git a/compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableWarnings.kt b/compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableWarnings.kt
index f0f37293165..c8a764df606 100644
--- a/compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableWarnings.kt
+++ b/compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableWarnings.kt
@@ -21,13 +21,13 @@ fun <V> SLRUMap<V>.getOrPut(value: V, l: List<V>) {
     takeV(<!NULLABLE_TYPE_PARAMETER_AGAINST_NOT_NULL_TYPE_PARAMETER!>value<!>)
     takeVList(<!NULLABLE_TYPE_PARAMETER_AGAINST_NOT_NULL_TYPE_PARAMETER!>l<!>)
 
-    takeE(<!NULLABLE_TYPE_PARAMETER_AGAINST_NOT_NULL_TYPE_PARAMETER!>value<!>)
-    takeEList(<!NULLABLE_TYPE_PARAMETER_AGAINST_NOT_NULL_TYPE_PARAMETER!>l<!>)
-    takeE(<!NULLABLE_TYPE_PARAMETER_AGAINST_NOT_NULL_TYPE_PARAMETER!>id(value)<!>)
+    takeE(<!TYPE_MISMATCH!>value<!>)
+    takeEList(<!TYPE_MISMATCH!>l<!>)
+    takeE(<!TYPE_MISMATCH!>id(value)<!>)
 
     if (value != null) {
         takeV(value)
-        takeE(value)
+        takeE(<!DEBUG_INFO_SMARTCAST!>value<!>)
         takeE(id(value))
     }
 }
diff --git a/compiler/testData/resolvedCalls/enhancedSignatures/optional/optionalOf.txt b/compiler/testData/resolvedCalls/enhancedSignatures/optional/optionalOf.txt
index 7638f81b666..26d2e30bafc 100644
--- a/compiler/testData/resolvedCalls/enhancedSignatures/optional/optionalOf.txt
+++ b/compiler/testData/resolvedCalls/enhancedSignatures/optional/optionalOf.txt
@@ -3,7 +3,7 @@ import java.util.*
 fun use() {
     val x: String? = "x"
     Optional.of(x)
-        // UNSAFE_CALL_ERROR
+        // SUCCESS
         // ORIGINAL:    fun <T : Any!> of(T): Optional<T> defined in java.util.Optional
         // SUBSTITUTED: fun <T : Any!> of(String): Optional<String> defined in java.util.Optional
 
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsCompiledJavaTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsCompiledJavaTestGenerated.java
index d46e1232411..cc4040602e9 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsCompiledJavaTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsCompiledJavaTestGenerated.java
@@ -925,6 +925,12 @@ public class ForeignAnnotationsCompiledJavaTestGenerated extends AbstractForeign
                 runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48261.kt");
             }
 
+            @Test
+            @TestMetadata("kt48778.kt")
+            public void testKt48778() throws Exception {
+                runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.kt");
+            }
+
             @Test
             @TestMetadata("methodWithTypeParameter.kt")
             public void testMethodWithTypeParameter() throws Exception {
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsCompiledJavaWithPsiClassReadingTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsCompiledJavaWithPsiClassReadingTestGenerated.java
index 0d8c86fb688..6651aebfe73 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsCompiledJavaWithPsiClassReadingTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsCompiledJavaWithPsiClassReadingTestGenerated.java
@@ -925,6 +925,12 @@ public class ForeignAnnotationsCompiledJavaWithPsiClassReadingTestGenerated exte
                 runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48261.kt");
             }
 
+            @Test
+            @TestMetadata("kt48778.kt")
+            public void testKt48778() throws Exception {
+                runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.kt");
+            }
+
             @Test
             @TestMetadata("methodWithTypeParameter.kt")
             public void testMethodWithTypeParameter() throws Exception {
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsSourceJavaTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsSourceJavaTestGenerated.java
index ac848241006..93ec1ec5715 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsSourceJavaTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ForeignAnnotationsSourceJavaTestGenerated.java
@@ -925,6 +925,12 @@ public class ForeignAnnotationsSourceJavaTestGenerated extends AbstractForeignAn
                 runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48261.kt");
             }
 
+            @Test
+            @TestMetadata("kt48778.kt")
+            public void testKt48778() throws Exception {
+                runTest("compiler/testData/diagnostics/foreignAnnotationsTests/java8Tests/misc/kt48778.kt");
+            }
+
             @Test
             @TestMetadata("methodWithTypeParameter.kt")
             public void testMethodWithTypeParameter() throws Exception {