Update Go version used for project to 1.16

When this update was done for Arduino CLI, some difficulties were encountered with the release build system, the
workarounds for which required some changes to the "DistTasks.yml" taskfile. The extensive comments added in that file
explain the situation.

Author: per1234

.github/workflows/check-go-task.yml

@@ -3,7 +3,7 @@ name: Check Go
 
 env:
   # See: https://github.com/actions/setup-go/tree/v2#readme
-  GO_VERSION: "1.14"
+  GO_VERSION: "1.16"
 
 # See: https://docs.github.com/en/actions/reference/events-that-trigger-workflows
 on:

.github/workflows/test.yml

@@ -47,7 +47,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v2
         with:
-          go-version: "1.14"
+          go-version: "1.16"
 
       - name: Install Taskfile
         uses: arduino/setup-task@v1

DistTasks.yml

@@ -19,7 +19,7 @@ version: "3"
 
 vars:
   CONTAINER: "docker.elastic.co/beats-dev/golang-crossbuild"
-  GO_VERSION: "1.14.7"
+  GO_VERSION: "1.16.4"
   CHECKSUM_FILE: "{{.VERSION}}-checksums.txt"
 
 tasks:
@@ -141,7 +141,7 @@ tasks:
       PLATFORM_DIR: "{{.PROJECT_NAME}}_linux_arm_7"
       BUILD_COMMAND: "go build -o {{.DIST_DIR}}/{{.PLATFORM_DIR}}/{{.PROJECT_NAME}} {{.LDFLAGS}}"
       BUILD_PLATFORM: "linux/armv7"
-      CONTAINER_TAG: "{{.GO_VERSION}}-arm"
+      CONTAINER_TAG: "{{.GO_VERSION}}-armhf"
       PACKAGE_PLATFORM: "Linux_ARMv7"
       PACKAGE_NAME: "{{.PROJECT_NAME}}_{{.VERSION}}_{{.PACKAGE_PLATFORM}}.tar.gz"
 
@@ -163,7 +163,35 @@ tasks:
       PLATFORM_DIR: "{{.PROJECT_NAME}}_linux_arm_6"
       BUILD_COMMAND: "go build -o {{.DIST_DIR}}/{{.PLATFORM_DIR}}/{{.PROJECT_NAME}} {{.LDFLAGS}}"
       BUILD_PLATFORM: "linux/armv6"
-      CONTAINER_TAG: "{{.GO_VERSION}}-arm"
+      # We are experiencing the following error with ARMv6 build:
+      #
+      #   # github.com/arduino/arduino-cli
+      #   net(.text): unexpected relocation type 296 (R_ARM_V4BX)
+      #   panic: runtime error: invalid memory address or nil pointer dereference
+      #   [signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x51ae53]
+      #
+      #   goroutine 1 [running]:
+      #   cmd/link/internal/loader.(*Loader).SymName(0xc000095c00, 0x0, 0xc0000958d8, 0x5a0ac)
+      #           /usr/local/go/src/cmd/link/internal/loader/loader.go:684 +0x53
+      #   cmd/link/internal/ld.dynrelocsym2(0xc000095880, 0x5a0ac)
+      #           /usr/local/go/src/cmd/link/internal/ld/data.go:777 +0x295
+      #   cmd/link/internal/ld.(*dodataState).dynreloc2(0xc007df9800, 0xc000095880)
+      #           /usr/local/go/src/cmd/link/internal/ld/data.go:794 +0x89
+      #   cmd/link/internal/ld.(*Link).dodata2(0xc000095880, 0xc007d00000, 0x60518, 0x60518)
+      #           /usr/local/go/src/cmd/link/internal/ld/data.go:1434 +0x4d4
+      #   cmd/link/internal/ld.Main(0x8729a0, 0x4, 0x8, 0x1, 0xd, 0xe, 0x0, 0x0, 0x6d7737, 0x12, ...)
+      #           /usr/local/go/src/cmd/link/internal/ld/main.go:302 +0x123a
+      #   main.main()
+      #           /usr/local/go/src/cmd/link/main.go:68 +0x1dc
+      #   Error: failed building for linux/armv6: exit status 2
+      #
+      # This seems to be a problem in the go builder 1.16.x that removed support for the R_ARM_V4BX instruction:
+      #    https://github.com/golang/go/pull/44998
+      #    https://groups.google.com/g/golang-codereviews/c/yzN80xxwu2E
+      #
+      # Until there is a fix released we must use a recent gcc for Linux_ARMv6 build, so for this
+      # build we select the debian10 based container.
+      CONTAINER_TAG: "{{.GO_VERSION}}-armel-debian10"
       PACKAGE_PLATFORM: "Linux_ARMv6"
       PACKAGE_NAME: "{{.PROJECT_NAME}}_{{.VERSION}}_{{.PACKAGE_PLATFORM}}.tar.gz"
 
@@ -207,6 +235,19 @@ tasks:
       PLATFORM_DIR: "{{.PROJECT_NAME}}_osx_darwin_amd64"
       BUILD_COMMAND: "go build -o {{.DIST_DIR}}/{{.PLATFORM_DIR}}/{{.PROJECT_NAME}} {{.LDFLAGS}}"
       BUILD_PLATFORM: "darwin/amd64"
-      CONTAINER_TAG: "{{.GO_VERSION}}-darwin"
+      # We are experiencing the following error with macOS_64bit build:
+      #
+      #   Undefined symbols for architecture x86_64:
+      #     "_clock_gettime", referenced from:
+      #         _runtime.walltime_trampoline in go.o
+      #   ld: symbol(s) not found for architecture x86_64
+      #   clang: error: linker command failed with exit code 1 (use -v to see invocation)
+      #
+      # The reason seems that go 1.16.x use a macos API which is available since 10.12
+      #    https://github.com/techknowlogick/xgo/issues/100#issuecomment-780894190
+      #
+      # To compile it we need an SDK >=10.12 so we use the debian10 based container that
+      # has the SDK 10.14 installed.
+      CONTAINER_TAG: "{{.GO_VERSION}}-darwin-debian10"
       PACKAGE_PLATFORM: "macOS_64bit"
       PACKAGE_NAME: "{{.PROJECT_NAME}}_{{.VERSION}}_{{.PACKAGE_PLATFORM}}.tar.gz"

docs/CONTRIBUTING.md

@@ -76,7 +76,7 @@ submitting a PR:
 
 To build Arduino Lint from sources you need the following tools to be available in your local environment:
 
-- [Go](https://golang.org/doc/install) version 1.14 or later
+- [Go](https://golang.org/doc/install) version 1.16 or later
 - [Taskfile](https://taskfile.dev/#/installation) to help you run the most common tasks from the command line
 
 If you want to run integration tests or work on documentation, you will also need:

docsgen/go.mod

@@ -1,6 +1,6 @@
 module github.com/arduino/arduino-lint/docsgen
 
-go 1.14
+go 1.16
 
 replace github.com/arduino/arduino-lint => ../
 

go.mod

@@ -1,6 +1,6 @@
 module github.com/arduino/arduino-lint
 
-go 1.14
+go 1.16
 
 require (
 	github.com/Microsoft/go-winio v0.4.16 // indirect