all: update Travis CI to Ubuntu Xenial

This lets us test with a more recent base, and should fix various
issues.

.travis.yml

@@ -1,14 +1,24 @@
 language: go
 
-go:
-  - "1.11"
+matrix:
+  include:
+  - dist: xenial
+    go: "1.11"
 
-before_install:
-  - echo "deb http://apt.llvm.org/trusty/ llvm-toolchain-trusty-7 main"            | sudo tee -a /etc/apt/sources.list
-  - echo "deb http://ppa.launchpad.net/ubuntu-toolchain-r/test/ubuntu trusty main" | sudo tee -a /etc/apt/sources.list
-  - sudo apt-get update -qq
-  - sudo apt-get install llvm-7-dev clang-7 libclang-7-dev binutils-arm-none-eabi qemu-system-arm --allow-unauthenticated -y
-  - sudo ln -s /usr/bin/clang-7 /usr/local/bin/cc # work around missing -no-pie in old GCC version
+addons:
+  apt:
+    sources:
+    - sourceline: 'ppa:ubuntu-toolchain-r'
+    - sourceline: 'deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-7 main'
+      key_url: 'https://apt.llvm.org/llvm-snapshot.gpg.key'
+    packages:
+    - llvm-7-dev
+    - clang-7
+    - libclang-7-dev
+    - binutils-arm-none-eabi
+    - qemu-system-arm
+    - gcc-avr
+    - avr-libc
 
 install:
   - curl https://raw.githubusercontent.com/golang/dep/master/install.sh | sh
@@ -26,7 +36,8 @@ script:
   - tinygo build -o test.nrf.elf       -target=nrf52840-mdk examples/blinky1
   - tinygo build -o blinky1.nrf51d.elf -target=pca10031     examples/blinky1
   - tinygo build -o blinky1.stm32.elf  -target=bluepill     examples/blinky1
-  - tinygo build -o blinky1.avr.o      -target=arduino      examples/blinky1 # TODO: avr-as/avr-gcc doesn't work
+  - tinygo build -o blinky1.avr.elf    -target=arduino      examples/blinky1
+  - tinygo build -o blinky1.avr.elf    -target=digispark    examples/blinky1
   - tinygo build -o blinky1.reel.elf   -target=reelboard    examples/blinky1
   - tinygo build -o blinky2.reel.elf   -target=reelboard    examples/blinky2
   - tinygo build -o blinky1.pca10056.elf    -target=pca10056     examples/blinky1

targets/nrf52.json

@@ -4,6 +4,7 @@
 	"build-tags": ["nrf52", "nrf"],
 	"cflags": [
 		"--target=armv7em-none-eabi",
+		"-mfloat-abi=soft",
 		"-Qunused-arguments",
 		"-DNRF52832_XXAA",
 		"-Ilib/CMSIS/CMSIS/Include"

targets/nrf52840.json

@@ -4,6 +4,7 @@
 	"build-tags": ["nrf52840", "nrf"],
 	"cflags": [
 		"--target=armv7em-none-eabi",
+		"-mfloat-abi=soft",
 		"-Qunused-arguments",
 		"-DNRF52840_XXAA",
 		"-Ilib/CMSIS/CMSIS/Include"