diff --git a/llvm/_core.cpp b/llvm/_core.cpp
index b0f1919..2f99ae3 100644
--- a/llvm/_core.cpp
+++ b/llvm/_core.cpp
@@ -200,8 +200,11 @@ _wLLVMGetNativeCodeFromModule(PyObject * self, PyObject * args)
 
     m = (LLVMModuleRef) PyCapsule_GetPointer(arg_m, NULL);
 
-    if ( !(bytes = LLVMGetNativeCodeFromModule(m, arg_use_asm, &len)) )
-        Py_RETURN_NONE;
+    std::string error;
+    bytes = LLVMGetNativeCodeFromModule(m, arg_use_asm, &len, error);
+    if ( !error.empty() ){
+        PyErr_SetString(PyExc_RuntimeError, error.c_str());
+    }
 
     ret = PyBytes_FromStringAndSize((char *)bytes, (Py_ssize_t)len);
     delete [] bytes;
@@ -1013,7 +1016,13 @@ _wLLVMTargetMachineLookup(PyObject * self, PyObject * args)
     if (!PyArg_ParseTuple(args, "sssi", &arch, &cpu, &features, &opt))
         return NULL;
 
-    LLVMTargetMachineRef tm = LLVMTargetMachineLookup(arch, cpu, features, opt);
+    std::string error;
+    LLVMTargetMachineRef tm = LLVMTargetMachineLookup(arch, cpu, features, opt,
+                                                      error);
+    if(!error.empty()){
+        PyErr_SetString(PyExc_RuntimeError, error.c_str());
+        return NULL;
+    }
     return ctor_LLVMTargetMachineRef(tm);
 }
 
@@ -1035,8 +1044,12 @@ _wLLVMTargetMachineEmitFile(PyObject * self, PyObject * args)
     tm = (LLVMTargetMachineRef) PyCapsule_GetPointer(arg_tm, NULL);
     m = (LLVMModuleRef) PyCapsule_GetPointer(arg_m, NULL);
 
-    if ( !(bytes = LLVMTargetMachineEmitFile(tm, m, arg_use_asm, &len)) )
-        Py_RETURN_NONE;
+    std::string error;
+    bytes = LLVMTargetMachineEmitFile(tm, m, arg_use_asm, &len, error);
+    if ( !error.empty() ){
+        PyErr_SetString(PyExc_RuntimeError, error.c_str());
+        return NULL;
+    }
 
     ret = PyBytes_FromStringAndSize((char *)bytes, (Py_ssize_t)len);
     delete [] bytes;
diff --git a/llvm/extra.cpp b/llvm/extra.cpp
index 7e27d10..2fde2ba 100644
--- a/llvm/extra.cpp
+++ b/llvm/extra.cpp
@@ -133,10 +133,10 @@ int LLVMInitializeNativeTargetAsmPrinter()
 
 
 LLVMTargetMachineRef LLVMTargetMachineLookup(const char *arch, const char *cpu,
-                                             const char *features, int opt)
+                                             const char *features, int opt,
+                                             std::string &error)
 {
     using namespace llvm;
-    std::string error;
     Triple TheTriple;
 
     // begin borrow from LLVM 3.2 code
@@ -153,7 +153,7 @@ LLVMTargetMachineRef LLVMTargetMachineLookup(const char *arch, const char *cpu,
     }
 
     if (!TheTarget) {
-        fprintf(stderr, "%s\n", error.c_str());
+        error = "Unknown arch";
         return NULL;
     }
 
@@ -165,7 +165,7 @@ LLVMTargetMachineRef LLVMTargetMachineLookup(const char *arch, const char *cpu,
     // end borrow from LLVM 3.2 code
 
     if (!TheTarget->hasTargetMachine()){
-        fprintf(stderr, "No target machine for %s\n", arch);
+        error = "No target machine for the arch";
         return NULL;
     }
 
@@ -177,7 +177,7 @@ LLVMTargetMachineRef LLVMTargetMachineLookup(const char *arch, const char *cpu,
                                      OptLevelMap[opt]);
 
     if (!tm){
-        fprintf(stderr, "Cannot create target machine!\n");
+        error = "Cannot create target machine";
         return NULL;
     }
     return wrap(tm);
@@ -198,7 +198,8 @@ void LLVMDisposeTargetMachine(LLVMTargetMachineRef tm){
 
 unsigned char* LLVMTargetMachineEmitFile(LLVMTargetMachineRef tmref,
                                          LLVMModuleRef modref,
-                                         int assembly, unsigned * lenp)
+                                         int assembly, unsigned * lenp,
+                                         std::string &error)
 {
     using namespace llvm;
     assert(lenp);
@@ -217,7 +218,7 @@ unsigned char* LLVMTargetMachineEmitFile(LLVMTargetMachineRef tmref,
     PassManager pm;
 
     if (!tm->getTargetData()){
-        fprintf(stderr, "No target data in target machine");
+        error = "No target data in target machine";
         return NULL;
     }
 
@@ -231,8 +232,7 @@ unsigned char* LLVMTargetMachineEmitFile(LLVMTargetMachineRef tmref,
     }
 
     if ( failed ) {
-        fprintf(stderr, "No support\n");
-        fprintf(stderr, "%s\n", tm->getTargetData()->getStringRepresentation().c_str());
+        error = "No support for emit file";
         return NULL;
     }
 
@@ -248,6 +248,7 @@ unsigned char* LLVMTargetMachineEmitFile(LLVMTargetMachineRef tmref,
     size_t bclen = bc.size();
     unsigned char *bytes = new unsigned char[bclen];
     if (!bytes){
+        error = "Out of memory";
         return NULL;
     }
     memcpy(bytes, bc.data(), bclen);
@@ -295,7 +296,7 @@ LLVMTargetDataRef LLVMTargetMachineGetTargetData(LLVMTargetMachineRef tm)
 }
 
 unsigned char* LLVMGetNativeCodeFromModule(LLVMModuleRef module, int assembly,
-                                           unsigned * lenp)
+                                           unsigned * lenp, std::string &error)
 {
     using namespace llvm;
     assert(lenp);
@@ -306,7 +307,7 @@ unsigned char* LLVMGetNativeCodeFromModule(LLVMModuleRef module, int assembly,
     // select native default machine
     TargetMachine * tm = EngineBuilder(modulep).selectTarget();
 
-    return LLVMTargetMachineEmitFile(wrap(tm), module, assembly, lenp);
+    return LLVMTargetMachineEmitFile(wrap(tm), module, assembly, lenp, error);
 }
 
 static
diff --git a/llvm/extra.h b/llvm/extra.h
index 832d725..a335a58 100644
--- a/llvm/extra.h
+++ b/llvm/extra.h
@@ -49,7 +49,8 @@ int LLVMInitializeNativeTargetAsmPrinter();
 
 
 LLVMTargetMachineRef LLVMTargetMachineLookup(const char *arch, const char *cpu,
-                                             const char *features, int opt);
+                                             const char *features, int opt,
+                                             std::string &error);
 
 /*
  * Wraps EngineBuilder::selectTarget
@@ -66,7 +67,8 @@ void LLVMDisposeTargetMachine(LLVMTargetMachineRef tm);
  */
 unsigned char* LLVMTargetMachineEmitFile(LLVMTargetMachineRef tmref,
                                          LLVMModuleRef modref,
-                                         int assembly, unsigned * lenp);
+                                         int assembly, unsigned * lenp,
+                                         std::string &error);
 
 /*
  * Wraps TargetMachine::getTargetData
@@ -107,7 +109,7 @@ void LLVMPrintRegisteredTargetsForVersion();
  * Wraps TargetMachine::addPassesToEmitFile
  */
 unsigned char* LLVMGetNativeCodeFromModule(LLVMModuleRef module, int assembly,
-                                           unsigned * lenp);
+                                           unsigned * lenp, std::string &error);
 
 /*
  * Wraps IRBuilder::CreateFence
diff --git a/test/targetmachines.py b/test/targetmachines.py
index a91411d..9ce85dd 100644
--- a/test/targetmachines.py
+++ b/test/targetmachines.py
@@ -42,6 +42,11 @@ class TestTargetMachines(unittest.TestCase):
         m.verify()
         return m, func
 
+    def _build_bad_archname(self):
+        with self.assertRaises(RuntimeError):
+            tm = TargetMachine.lookup("ain't no arch name")
+
+
 if __name__ == '__main__':
     unittest.main()