Merge pull request #10 from snapcore/fix-cross-building

use on/to in build-packages, fix --target-arch use

README.md

@@ -31,8 +31,7 @@ projects better than what is available with Github issues.
 
 To build the gadget snap locally on an armhf system please use `snapcraft`.
 
-To cross build this gadget snap on a PC please install the gcc-arm-linux-gnueabihf package
-before running `snapcraft`
+To cross build this gadget snap on a PC please run `snapcraft --target-arch=armhf`
 
 ## Launchpad Mirror and Automatic Builds.
 

snapcraft.yaml

@@ -1,5 +1,5 @@
 name: pi2
-version: 16.04-0.18
+version: 16.04-0.19
 summary: Raspberry Pi 2 support package
 description: |
  Support files for booting Raspberry Pi
@@ -10,18 +10,14 @@ confinement: strict
 grade: stable
 parts:
   uboot:
-    plugin: make
+    plugin: nil
     source: git://git.denx.de/u-boot.git
     source-branch: v2017.05
     prepare: |
       git apply ../../../uboot.patch
       make rpi_2_defconfig
     build: |
       if [ "$(arch)" = "x86_64" ]; then
-        if [ ! -x /usr/bin/arm-linux-gnueabihf-gcc ]; then
-          echo "ERROR: You are cross building this snap, please install gcc-arm-linux-gnueabihf"
-          exit 1
-        fi
         CROSS_COMPILE=arm-linux-gnueabihf- make
       else
         make
@@ -37,6 +33,8 @@ parts:
       - device-tree-compiler
       - libpython2.7-dev
       - python-minimal
+      - on amd64 to armhf:
+          - gcc-arm-linux-gnueabihf:amd64
   boot-firmware:
     plugin: nil
     source: .