diff --git a/translator/src/main/kotlin/org/kotlinnative/translator/BlockCodegen.kt b/translator/src/main/kotlin/org/kotlinnative/translator/BlockCodegen.kt
index e3b12a32f55..0af24d3fae3 100644
--- a/translator/src/main/kotlin/org/kotlinnative/translator/BlockCodegen.kt
+++ b/translator/src/main/kotlin/org/kotlinnative/translator/BlockCodegen.kt
@@ -90,7 +90,7 @@ abstract class BlockCodegen(val state: TranslationState, val variableManager: Va
     fun evaluateExpression(expr: PsiElement?, scopeDepth: Int): LLVMSingleValue? {
         return when (expr) {
             is KtBlockExpression -> {
-                expressionWalker(expr.firstChild, null, scopeDepth + 1)
+                expressionWalker(expr.firstChild, breakLabel = null, scopeDepth = scopeDepth + 1)
                 return null
             }
             is KtBinaryExpression -> evaluateBinaryExpression(expr, scopeDepth)
@@ -636,6 +636,18 @@ abstract class BlockCodegen(val state: TranslationState, val variableManager: Va
                 codeBuilder.storeVariable(firstOp, resultOp)
                 return oldValue
             }
+            KtTokens.EXCLEXCL -> {
+                val nullLabel = codeBuilder.getNewLabel(prefix = "nullCheck")
+                val notNullLabel = codeBuilder.getNewLabel(prefix = "nullCheck")
+                val nullCheck = codeBuilder.nullCheck(firstOp)
+                codeBuilder.addCondition(nullCheck, nullLabel, notNullLabel)
+
+                codeBuilder.markWithLabel(nullLabel)
+                codeBuilder.addExceptionCall("KotlinNullPointerException")
+                codeBuilder.addUnconditionalJump(notNullLabel)
+                codeBuilder.markWithLabel(notNullLabel)
+                return firstOp
+            }
             else -> throw UnsupportedOperationException()
         }
     }
@@ -895,7 +907,8 @@ abstract class BlockCodegen(val state: TranslationState, val variableManager: Va
 
         when (expressionType) {
             is LLVMVoidType,
-            is LLVMNullType -> {}
+            is LLVMNullType -> {
+            }
             is LLVMReferenceType -> codeBuilder.allocStaticVar(resultVariable, asValue = true)
             else -> codeBuilder.allocStackVar(resultVariable, asValue = true)
         }
diff --git a/translator/src/main/kotlin/org/kotlinnative/translator/llvm/LLVMBuilder.kt b/translator/src/main/kotlin/org/kotlinnative/translator/llvm/LLVMBuilder.kt
index 63d994de64d..7207507eef3 100644
--- a/translator/src/main/kotlin/org/kotlinnative/translator/llvm/LLVMBuilder.kt
+++ b/translator/src/main/kotlin/org/kotlinnative/translator/llvm/LLVMBuilder.kt
@@ -1,9 +1,6 @@
 package org.kotlinnative.translator.llvm
 
-import org.kotlinnative.translator.llvm.types.LLVMCharType
-import org.kotlinnative.translator.llvm.types.LLVMIntType
-import org.kotlinnative.translator.llvm.types.LLVMStringType
-import org.kotlinnative.translator.llvm.types.LLVMType
+import org.kotlinnative.translator.llvm.types.*
 import java.util.*
 
 class LLVMBuilder(val arm: Boolean = false) {
@@ -18,22 +15,29 @@ class LLVMBuilder(val arm: Boolean = false) {
         initBuilder()
     }
 
+    var exceptions: Map<String, LLVMVariable> = mapOf()
+
     private fun initBuilder() {
         val declares = arrayOf(
                 "declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i32, i1)",
-                "declare i8* @malloc_static(i32)")
+                "declare i8* @malloc_static(i32)",
+                "declare i32 @printf(i8*, ...)",
+                "declare void @abort()")
 
         declares.forEach { globalCode.appendln(it) }
 
+        exceptions = mapOf(
+                Pair("KotlinNullPointerException", initializeString("Exception in thread main kotlin.KotlinNullPointerException")))
+
         val funcAttributes = """attributes #0 = { nounwind "stack-protector-buffer-size"="8" "target-cpu"="cortex-m3" "target-features"="+hwdiv,+strict-align" }"""
         if (arm) {
             globalCode.appendln(funcAttributes)
         }
     }
 
-    fun getNewVariable(type: LLVMType, pointer: Int = 0, kotlinName: String? = null, scope: LLVMScope = LLVMRegisterScope()): LLVMVariable {
+    fun getNewVariable(type: LLVMType, pointer: Int = 0, kotlinName: String? = null, scope: LLVMScope = LLVMRegisterScope(), prefix: String = "var"): LLVMVariable {
         variableCount++
-        return LLVMVariable("var$variableCount", type, kotlinName, scope, pointer)
+        return LLVMVariable("${prefix}$variableCount", type, kotlinName, scope, pointer)
     }
 
     fun getNewLabel(scope: LLVMScope = LLVMRegisterScope(), prefix: String): LLVMLabel {
@@ -77,9 +81,15 @@ class LLVMBuilder(val arm: Boolean = false) {
         localCode.appendln("ret $type $value")
     }
 
+    private fun initializeString(string: String): LLVMVariable {
+        val result = getNewVariable(LLVMStringType(string.length), pointer = 0, scope = LLVMVariableScope(), prefix = "exceptions.str.")
+        addStringConstant(result, string)
+        return result
+    }
+
     fun addStringConstant(variable: LLVMVariable, value: String) {
         val type = variable.type as LLVMStringType
-        globalCode.appendln("$variable = private unnamed_addr constant  ${type.fullType()} c\"$value\\00\", align 1")
+        globalCode.appendln("$variable = private unnamed_addr constant  ${type.fullType()} c\"${value.replace("\"", "\\\"")}\\00\", align 1")
     }
 
     fun addGlobalInitialize(target: LLVMVariable, fields: ArrayList<LLVMVariable>, initializers: Map<LLVMVariable, String>, classType: LLVMType) {
@@ -121,6 +131,17 @@ class LLVMBuilder(val arm: Boolean = false) {
         localCode.appendln(code)
     }
 
+    fun nullCheck(variable: LLVMVariable): LLVMVariable {
+        val result = getNewVariable(LLVMBooleanType(), pointer = 0)
+
+        val loaded = getNewVariable(variable.type, pointer = variable.pointer - 1)
+        loadVariable(loaded, variable)
+
+        val code = "$result = icmp eq ${loaded.getType()} null, $loaded"
+        localCode.appendln(code)
+        return result
+    }
+
     fun addComment(comment: String) {
         localCode.appendln("; " + comment)
     }
@@ -218,6 +239,17 @@ class LLVMBuilder(val arm: Boolean = false) {
         return empty
     }
 
+    fun addExceptionCall(exceptionName: String) {
+        val exception = exceptions[exceptionName]
+        val printResult = getNewVariable(LLVMIntType(), pointer = 0)
+        localCode.appendln("$printResult = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds (${(exception!!.type as LLVMStringType).fullType()}* $exception, i32 0, i32 0))")
+        addFunctionCall(LLVMVariable("abort", LLVMVoidType(), scope = LLVMVariableScope()), emptyList())
+    }
+
+    fun addFunctionCall(functionName: LLVMVariable, arguments: List<LLVMVariable>) {
+        localCode.appendln("call ${functionName.type} $functionName(${arguments.joinToString { it -> "${it.type} $it" }})")
+    }
+
     fun memcpy(castedDst: LLVMVariable, castedSrc: LLVMVariable, size: Int, align: Int = 4, volatile: Boolean = false) {
         val code = "call void @llvm.memcpy.p0i8.p0i8.i64(i8* $castedDst, i8* $castedSrc, i64 $size, i32 $align, i1 $volatile)"
         localCode.appendln(code)
diff --git a/translator/src/test/kotlin/tests/input/nullable_1.txt b/translator/src/test/kotlin/tests/input/nullable_1.txt
index 77d39cc8c32..3bab68cb5b7 100644
--- a/translator/src/test/kotlin/tests/input/nullable_1.txt
+++ b/translator/src/test/kotlin/tests/input/nullable_1.txt
@@ -1,2 +1,3 @@
-nullable_test_Int(1) == 1
-nullable_test_2_Int(4) == 5
+nullable_1_test_Int(1) == 1
+nullable_1_test_2_Int(4) == 5
+nullable_1_test_2_npe_operator_Int(23) == 578
diff --git a/translator/src/test/kotlin/tests/kotlin/nullable_1.kt b/translator/src/test/kotlin/tests/kotlin/nullable_1.kt
index 2ec1b26bbb2..f916d101a78 100644
--- a/translator/src/test/kotlin/tests/kotlin/nullable_1.kt
+++ b/translator/src/test/kotlin/tests/kotlin/nullable_1.kt
@@ -1,16 +1,21 @@
+class nullable_1_MyAwesomeClass(var i: Int)
 
-class MyAwesomeClass(var i: Int)
-
-fun nullable_test(i: Int): Int {
-    var x: MyAwesomeClass? = null
-    x = MyAwesomeClass(i)
+fun nullable_1_test(i: Int): Int {
+    var x: nullable_1_MyAwesomeClass? = null
+    x = nullable_1_MyAwesomeClass(i)
     return x.i
 }
 
-fun nullable_test_2(i: Int): Int {
-    var x: MyAwesomeClass? = MyAwesomeClass(i)
+fun nullable_1_test_2(i: Int): Int {
+    var x: nullable_1_MyAwesomeClass? = nullable_1_MyAwesomeClass(i)
     x = null
-    x = MyAwesomeClass(i)
+    x = nullable_1_MyAwesomeClass(i)
 
     return x.i + 1
+}
+
+fun nullable_1_test_2_npe_operator(i: Int): Int {
+    val x: nullable_1_MyAwesomeClass? = nullable_1_MyAwesomeClass(i)
+    x!!
+    return x.i + 555
 }
\ No newline at end of file