diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/ConstraintSystemBuilderImpl.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/ConstraintSystemBuilderImpl.kt
index 16f505f84f2..9736a88dfc2 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/ConstraintSystemBuilderImpl.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/ConstraintSystemBuilderImpl.kt
@@ -378,8 +378,8 @@ public class ConstraintSystemBuilderImpl : ConstraintSystem.Builder {
     }
 
     override fun build(): ConstraintSystem {
-        return ConstraintSystemSnapshot(allTypeParameterBounds, externalTypeParameters, usedInBounds, errors, initialConstraints,
-                                        originalToVariables, variablesToOriginal)
+        return ConstraintSystemImpl(allTypeParameterBounds, externalTypeParameters, usedInBounds, errors, initialConstraints,
+                                    originalToVariables, variablesToOriginal)
     }
 }
 
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/ConstraintSystemSnapshot.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/ConstraintSystemImpl.kt
similarity index 99%
rename from compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/ConstraintSystemSnapshot.kt
rename to compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/ConstraintSystemImpl.kt
index 82988c0c4a7..1e6ddbd50b3 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/ConstraintSystemSnapshot.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/ConstraintSystemImpl.kt
@@ -33,7 +33,7 @@ import org.jetbrains.kotlin.types.typeUtil.getNestedArguments
 import org.jetbrains.kotlin.types.typeUtil.makeNotNullable
 import java.util.*
 
-class ConstraintSystemSnapshot(
+class ConstraintSystemImpl(
         private val allTypeParameterBounds: Map<TypeParameterDescriptor, TypeBoundsImpl>,
         private val externalTypeParameters: Set<TypeParameterDescriptor>,
         private val usedInBounds: Map<TypeParameterDescriptor, MutableList<TypeBounds.Bound>>,