Add support for OSX up to 10.10 and CLI Tools

- Support using OSX versions 10.9 and 10.10 as the compilation host.
  Please note that the prebuilt darwin-x86 gcc is missing an upstream
  patch that properly identifies 10.10 as newer than 10.2, which
  restricts mac_sdk_versions_supported to 10.9.
- Support using Xcode Command Line Tools, waiving the requirement for
  installing the full Xcode development suite for 600k worth of C++
  headers.

These build modifications have been verified by successfully compiling a
cm12-hammerhead image from scratch on a OSX Yosemite 10.10.1 host with
Xcode Command Line Tools 6.1.1 installed.

Change-Id: Id1741ef583d186eb6a42093e5111431ae7b08a2c

1 files changed, 18 insertions, 3 deletions

diff --git a/core/combo/mac_version.mk b/core/combo/mac_version.mk
index 6defba7..d18e4c5 100644
--- a/core/combo/mac_version.mk
+++ b/core/combo/mac_version.mk
@@ -9,17 +9,19 @@ ifndef build_mac_version
 
 build_mac_version := $(shell sw_vers -productVersion)
 
-mac_sdk_versions_supported :=  10.6 10.7 10.8 10.9
+# Caution: Do not add 10.10 to this list until the prebuilts/darwin-x86 toolchains are updated.
+#          In the meantime, setting mac_sdk_version to 10.9 works on Yosemite (verified on 10.10.1).
+mac_sdk_versions_supported := 10.6 10.7 10.8 10.9
 ifneq ($(strip $(MAC_SDK_VERSION)),)
 mac_sdk_version := $(MAC_SDK_VERSION)
 ifeq ($(filter $(mac_sdk_version),$(mac_sdk_versions_supported)),)
 $(warning ****************************************************************)
-$(warning * MAC_SDK_VERSION $(MAC_SDK_VERSION) isn't one of the supported $(mac_sdk_versions_supported))
+$(warning * MAC_SDK_VERSION $(MAC_SDK_VERSION) isn\'t one of the supported $(mac_sdk_versions_supported))
 $(warning ****************************************************************)
 $(error Stop.)
 endif
 else
-mac_sdk_versions_installed := $(shell xcodebuild -showsdks | grep macosx | sort | sed -e "s/.*macosx//g")
+mac_sdk_versions_installed := $(shell xcodebuild -showsdks 2> /dev/null | grep macosx | sort | sed -e "s/.*macosx//g")
 mac_sdk_version := $(firstword $(filter $(mac_sdk_versions_installed), $(mac_sdk_versions_supported)))
 ifeq ($(mac_sdk_version),)
 mac_sdk_version := $(firstword $(mac_sdk_versions_supported))
@@ -27,6 +29,18 @@ endif
 endif
 
 mac_sdk_path := $(shell xcode-select -print-path)
+
+ifeq ($(strip "$(mac_sdk_path)"), "/Library/Developer/CommandLineTools")
+# Accept any modern version of Apple Command Line Tools
+mac_sdk_root := /
+
+# Override mac_sdk_version with build_mac_version (aka the version of the OSX host), but assume the latest
+# supported mac_sdk_version if the build_mac_version is not recognized.
+mac_sdk_version := $(shell echo $(build_mac_version) | cut -d '.' -f 1,2)
+ifeq ($(filter $(mac_sdk_version),$(mac_sdk_versions_supported)),)
+mac_sdk_version := $(lastword $(mac_sdk_versions_supported))
+endif
+else
 # try /Applications/Xcode*.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.?.sdk
 #  or /Volume/Xcode/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.?.sdk
 mac_sdk_root := $(mac_sdk_path)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX$(mac_sdk_version).sdk
@@ -40,6 +54,7 @@ $(warning * Can not find SDK $(mac_sdk_version) at $(mac_sdk_root))
 $(warning *****************************************************)
 $(error Stop.)
 endif
+endif # $(mac_sdk_path)
 
 ifeq ($(mac_sdk_version),10.6)
   gcc_darwin_version := 10