Update GO_VERSION to 1.18.3 (#3301)

Update GO_VERSION to 1.18.3

GO_VERSION

@@ -1 +1 @@
-1.17.5
+1.18.3

Makefile

@@ -55,7 +55,10 @@ static-with-pause:
 xplatform-build:
 	GOOS=linux GOARCH=arm64 ./scripts/build true "" false
 	GOOS=windows GOARCH=amd64 ./scripts/build true "" false
-	GOOS=darwin GOARCH=amd64 ./scripts/build true "" false
+	# Agent and its dependencies on Go 1.18.x are not compatible with Mac (Darwin).
+	# Mac is not a supported target platform for Agent, so commenting out 
+	# cross-platform build step for Mac temporarily.
+	# GOOS=darwin GOARCH=amd64 ./scripts/build true "" false
 
 BUILDER_IMAGE="amazon/amazon-ecs-agent-build:make"
 .builder-image-stamp: scripts/dockerfiles/Dockerfile.build
@@ -340,8 +343,8 @@ GOPATH=$(shell go env GOPATH)
 	go get github.com/golang/mock/mockgen
 	cd "${GOPATH}/src/github.com/golang/mock/mockgen" && git checkout 1.3.1 && go get ./... && go install ./... && cd -
 	go get golang.org/x/tools/cmd/goimports
-	GO111MODULE=on go get github.com/fzipp/gocyclo/cmd/[email protected]
-	GO111MODULE=on go get honnef.co/go/tools/cmd/staticcheck@v0.2.1
+	GO111MODULE=on go install github.com/fzipp/gocyclo/cmd/[email protected]
+	GO111MODULE=on go install honnef.co/go/tools/cmd/staticcheck@v0.3.2
 	touch .get-deps-stamp
 
 get-deps: .get-deps-stamp
@@ -351,9 +354,9 @@ get-deps-init:
 	go get golang.org/x/tools/cmd/cover
 	go get github.com/golang/mock/mockgen
 	cd "${GOPATH}/src/github.com/golang/mock/mockgen" && git checkout 1.3.1 && go get ./... && go install ./... && cd -
-	GO111MODULE=on go get github.com/fzipp/gocyclo/cmd/[email protected]
+	GO111MODULE=on go install github.com/fzipp/gocyclo/cmd/[email protected]
 	go get golang.org/x/tools/cmd/goimports
-	GO111MODULE=on go get honnef.co/go/tools/cmd/staticcheck@v0.2.1
+	GO111MODULE=on go install honnef.co/go/tools/cmd/staticcheck@v0.3.2
 
 amazon-linux-sources.tgz:
 	./scripts/update-version.sh

agent/credentials/manager.go

@@ -68,14 +68,10 @@ type IAMRoleCredentials struct {
 type TaskIAMRoleCredentials struct {
 	ARN                string
 	IAMRoleCredentials IAMRoleCredentials
-	lock               sync.RWMutex
 }
 
 // GetIAMRoleCredentials returns the IAM role credentials in the task IAM role struct
 func (role *TaskIAMRoleCredentials) GetIAMRoleCredentials() IAMRoleCredentials {
-	role.lock.RLock()
-	defer role.lock.RUnlock()
-
 	return role.IAMRoleCredentials
 }