[Patch 1/2] BaseTools GNUmakefile: Move HOST_ARCH detection into common makefile

[Liming Gao <liming.gao@intel.com>]

With this change, enter single tool directory, make can pass.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
---
 BaseTools/Source/C/Makefiles/header.makefile | 28 ++++++++++++++++++++++++++--
 1 file changed, 26 insertions(+), 2 deletions(-)

diff --git a/BaseTools/Source/C/Makefiles/header.makefile b/BaseTools/Source/C/Makefiles/header.makefile
index e034da2..0976973 100644
--- a/BaseTools/Source/C/Makefiles/header.makefile
+++ b/BaseTools/Source/C/Makefiles/header.makefile
@@ -6,7 +6,7 @@
 # HOST_ARCH = ia64 or IA64 for IA64 build
 # HOST_ARCH = Arm or ARM for ARM build
 #
-# Copyright (c) 2007 - 2016, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) 2007 - 2018, Intel Corporation. All rights reserved.<BR>
 # This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.    The full text of the license may be found at
@@ -15,7 +15,31 @@
 # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 
-HOST_ARCH ?= IA32
+ifndef HOST_ARCH
+  #
+  # If HOST_ARCH is not defined, then we use 'uname -m' to attempt
+  # try to figure out the appropriate HOST_ARCH.
+  #
+  uname_m = $(shell uname -m)
+  $(info Attempting to detect HOST_ARCH from 'uname -m': $(uname_m))
+  ifneq (,$(strip $(filter $(uname_m), x86_64 amd64)))
+    HOST_ARCH=X64
+  endif
+  ifeq ($(patsubst i%86,IA32,$(uname_m)),IA32)
+    HOST_ARCH=IA32
+  endif
+  ifneq (,$(findstring aarch64,$(uname_m)))
+    HOST_ARCH=AARCH64
+  endif
+  ifneq (,$(findstring arm,$(uname_m)))
+    HOST_ARCH=ARM
+  endif
+  ifndef HOST_ARCH
+    $(info Could not detected HOST_ARCH from uname results)
+    $(error HOST_ARCH is not defined!)
+  endif
+  $(info Detected HOST_ARCH of $(HOST_ARCH) using uname.)
+endif
 
 CYGWIN:=$(findstring CYGWIN, $(shell uname -s))
 LINUX:=$(findstring Linux, $(shell uname -s))
-- 
2.8.0.windows.1