diff --git a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosisCompilerTestFE10TestdataTestGenerated.java b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosisCompilerTestFE10TestdataTestGenerated.java
index 8d7a5b22f4d..d8279553742 100644
--- a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosisCompilerTestFE10TestdataTestGenerated.java
+++ b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosisCompilerTestFE10TestdataTestGenerated.java
@@ -21356,6 +21356,12 @@ public class DiagnosisCompilerTestFE10TestdataTestGenerated extends AbstractDiag
                 runTest("compiler/testData/diagnostics/tests/multiplatform/implFakeOverride.kt");
             }
 
+            @Test
+            @TestMetadata("incDecOperatorsInExpectClass.kt")
+            public void testIncDecOperatorsInExpectClass() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/multiplatform/incDecOperatorsInExpectClass.kt");
+            }
+
             @Test
             @TestMetadata("incompatibles.kt")
             public void testIncompatibles() throws Exception {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java
index 36f89435ace..403c4e5d884 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java
@@ -21362,6 +21362,12 @@ public class FirOldFrontendDiagnosticsTestGenerated extends AbstractFirDiagnosti
                 runTest("compiler/testData/diagnostics/tests/multiplatform/implFakeOverride.kt");
             }
 
+            @Test
+            @TestMetadata("incDecOperatorsInExpectClass.kt")
+            public void testIncDecOperatorsInExpectClass() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/multiplatform/incDecOperatorsInExpectClass.kt");
+            }
+
             @Test
             @TestMetadata("incompatibles.kt")
             public void testIncompatibles() throws Exception {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsWithLightTreeTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsWithLightTreeTestGenerated.java
index 05d6e5f6748..90bc1154bae 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsWithLightTreeTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsWithLightTreeTestGenerated.java
@@ -21356,6 +21356,12 @@ public class FirOldFrontendDiagnosticsWithLightTreeTestGenerated extends Abstrac
                 runTest("compiler/testData/diagnostics/tests/multiplatform/implFakeOverride.kt");
             }
 
+            @Test
+            @TestMetadata("incDecOperatorsInExpectClass.kt")
+            public void testIncDecOperatorsInExpectClass() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/multiplatform/incDecOperatorsInExpectClass.kt");
+            }
+
             @Test
             @TestMetadata("incompatibles.kt")
             public void testIncompatibles() throws Exception {
diff --git a/compiler/testData/diagnostics/tests/IncDecOperatorsInExpectClass.fir.kt b/compiler/testData/diagnostics/tests/IncDecOperatorsInExpectClass.fir.kt
new file mode 100644
index 00000000000..b5b055f8731
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/IncDecOperatorsInExpectClass.fir.kt
@@ -0,0 +1,13 @@
+// In FIR, declaring the same `expect` and `actual` classes in one compiler module is not possible (see KT-55177). Hence the `.fir.kt` test
+// expects a diagnostic here. The multi-module test corresponding to this test is called: `multiplatform/incDecOperatorsInExpectClass.kt`.
+
+// !LANGUAGE: +MultiPlatformProjects
+// SKIP_TXT
+// Issue: KT-49714
+
+expect class Counter {
+    operator fun inc(): Counter
+    operator fun dec(): Counter
+}
+
+<!ACTUAL_WITHOUT_EXPECT!>actual typealias Counter = Int<!>
diff --git a/compiler/testData/diagnostics/tests/IncDecOperatorsInExpectClass.kt b/compiler/testData/diagnostics/tests/IncDecOperatorsInExpectClass.kt
index cb90b5e2b99..581eb66e89d 100644
--- a/compiler/testData/diagnostics/tests/IncDecOperatorsInExpectClass.kt
+++ b/compiler/testData/diagnostics/tests/IncDecOperatorsInExpectClass.kt
@@ -1,4 +1,6 @@
-// FIR_IDENTICAL
+// In FIR, declaring the same `expect` and `actual` classes in one compiler module is not possible (see KT-55177). Hence the `.fir.kt` test
+// expects a diagnostic here. The multi-module test corresponding to this test is called: `multiplatform/incDecOperatorsInExpectClass.kt`.
+
 // !LANGUAGE: +MultiPlatformProjects
 // SKIP_TXT
 // Issue: KT-49714
diff --git a/compiler/testData/diagnostics/tests/multiplatform/incDecOperatorsInExpectClass.kt b/compiler/testData/diagnostics/tests/multiplatform/incDecOperatorsInExpectClass.kt
new file mode 100644
index 00000000000..cce27b4ee51
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/multiplatform/incDecOperatorsInExpectClass.kt
@@ -0,0 +1,12 @@
+// FIR_IDENTICAL
+// Issue: KT-49714
+
+// MODULE: common
+// TARGET_PLATFORM: Common
+expect class Counter {
+    operator fun inc(): Counter
+    operator fun dec(): Counter
+}
+
+// MODULE: main()()(common)
+actual typealias Counter = Int
diff --git a/compiler/testData/diagnostics/tests/multiplatform/incDecOperatorsInExpectClass.txt b/compiler/testData/diagnostics/tests/multiplatform/incDecOperatorsInExpectClass.txt
new file mode 100644
index 00000000000..43f6f0dc15e
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/multiplatform/incDecOperatorsInExpectClass.txt
@@ -0,0 +1,15 @@
+// -- Module: <common> --
+package
+
+public final expect class Counter {
+    public final expect operator fun dec(): Counter
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public final expect operator fun inc(): Counter
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+// -- Module: <main> --
+package
+
+public actual typealias Counter = kotlin.Int
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 7a535aa9bd5..a4ed83c7306 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
@@ -21362,6 +21362,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
                 runTest("compiler/testData/diagnostics/tests/multiplatform/implFakeOverride.kt");
             }
 
+            @Test
+            @TestMetadata("incDecOperatorsInExpectClass.kt")
+            public void testIncDecOperatorsInExpectClass() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/multiplatform/incDecOperatorsInExpectClass.kt");
+            }
+
             @Test
             @TestMetadata("incompatibles.kt")
             public void testIncompatibles() throws Exception {