Remove support for Go < 1.11

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        go: [ '1.9', '1.10', '1.11', '1.12', '1.13' ]
+        go: [ '1.11', '1.12', '1.13', '1.14' ]
 
     steps:
     - uses: actions/checkout@v1

Makefile

-SOURCES = $(shell script/build files)
+SOURCES = $(shell go list -f '{{range .GoFiles}}{{$$.Dir}}/{{.}}\
+{{end}}' ./...)
 SOURCE_DATE_EPOCH ?= $(shell date +%s)
 BUILD_DATE = $(shell date -u -d "@$(SOURCE_DATE_EPOCH)" '+%d %b %Y' 2>/dev/null || date -u -r "$(SOURCE_DATE_EPOCH)" '+%d %b %Y')
 HUB_VERSION = $(shell bin/hub version | tail -1)
-FLAGS_ALL = $(shell go version | grep -q 'go1.[89]' || echo 'all=')
-export GOFLAGS := $(shell go version | grep -q 'go1.1[^0]' && echo '-mod=vendor')
-export LDFLAGS := -extldflags '$(LDFLAGS)'
-export GCFLAGS := $(FLAGS_ALL)-trimpath '$(PWD)'
-export ASMFLAGS := $(FLAGS_ALL)-trimpath '$(PWD)'
 
-ifneq ($(GOFLAGS),)
-	export GO111MODULE=on
-	unexport GOPATH
-endif
+export GOFLAGS := -mod=vendor
+export GO111MODULE=on
+unexport GOPATH
+
+export LDFLAGS := -extldflags '$(LDFLAGS)'
+export GCFLAGS := all=-trimpath '$(PWD)'
+export ASMFLAGS := all=-trimpath '$(PWD)'
 
 MIN_COVERAGE = 90.2
 

README.md

@@ -85,7 +85,7 @@ it to your [repository secrets][].
 Prerequisites for building from source are:
 
 * `make`
-* [Go 1.9+](https://golang.org/doc/install)
+* [Go 1.11+](https://golang.org/doc/install)
 
 Clone this repository and run `make install`:
 

script/test

@@ -32,7 +32,6 @@ STATUS=0
 trap "exit 1" INT
 
 check_formatting() {
-  [[ "$(go version)" != *" go1.8."* ]] || return 0
   gofmt -l -w . >/dev/null
   git checkout -- vendor
   if ! git diff -U1 --exit-code; then