[NaCl SDK] Enable linux host build for nacl_io and nacl_io_tests.

native_client_sdk/src/tools/nacl_gcc.mk

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 #
 # GNU Make based build file.  For details on GNU Make see:
 #   http://www.gnu.org/software/make/manual/make.html
 #
 
 
@@ skipping 434 matching lines @@
 else
 LIB_NAME = lib64
 endif
 
 
 ifeq (newlib,$(TOOLCHAIN))
 GDB_DEBUG_TARGET = $(abspath $(OUTDIR))/$(TARGET)_$(SYSARCH).nexe
 else
 GDB_DEBUG_TARGET = $(abspath $(OUTDIR))/$(LIB_NAME)/runnable-ld.so
 endif
+
+ifdef STANDALONE
+run: all
+ifndef NACL_ARCH
+        $(error Cannot run in sel_ldr unless $$NACL_ARCH is set)
+endif
+        $(SEL_LDR_PATH) $(SEL_LDR_ARGS) $(OUTDIR)/$(TARGET)_$(NACL_ARCH).nexe -- $(EXE_ARGS)
+
+debug: all
+ifndef NACL_ARCH
+        $(error Cannot run in sel_ldr unless $$NACL_ARCH is set)
+endif
+        $(SEL_LDR_PATH) -d $(SEL_LDR_ARGS) $(OUTDIR)/$(TARGET)_$(NACL_ARCH).nexe -- $(EXE_ARGS)
+endif