diff --git a/Makefile.common b/Makefile.common
index b65017c3f..18cae8922 100644
--- a/Makefile.common
+++ b/Makefile.common
@@ -29,23 +29,27 @@ GO           ?= go
 GOFMT        ?= $(GO)fmt
 FIRST_GOPATH := $(firstword $(subst :, ,$(shell $(GO) env GOPATH)))
 GOOPTS       ?=
-ifneq (,$(wildcard go.mod))
+unexport GOVENDOR
 ifeq ($(shell $(GO) version | grep -E 'go1\.(10|[0-9])\.'),)
-ifneq (,$(wildcard vendor))
-	# Always use the local vendor/ directory to satisfy the dependencies.
-	GOOPTS      := $(GOOPTS) -mod=vendor
-endif
-	# Enable module support forcibly just in case the directory is inside GOPATH (and Travis CI).
-	GO111MODULE := on
+	ifneq (,$(wildcard go.mod))
+		# Enforce Go modules support just in case the directory is inside GOPATH (and for Travis CI).
+		GO111MODULE := on
 
-	unexport GOVENDOR
+		ifneq (,$(wildcard vendor))
+			# Always use the local vendor/ directory to satisfy the dependencies.
+			GOOPTS := $(GOOPTS) -mod=vendor
+		endif
+	endif
 else
+	ifneq (,$(wildcard go.mod))
+		ifneq (,$(wildcard vendor))
 $(warning This repository requires Go >= 1.11 because of Go modules)
 $(warning Some recipes may not work as expected as the current Go runtime is '$(shell $(GO) version)')
-endif
-else
-# This repository isn't using Go modules (yet).
-	GOVENDOR    := $(FIRST_GOPATH)/bin/govendor
+		endif
+	else
+		# This repository isn't using Go modules (yet).
+		GOVENDOR := $(FIRST_GOPATH)/bin/govendor
+	endif
 
 	unexport GO111MODULE
 endif
@@ -110,7 +114,7 @@ common-vet:
 .PHONY: common-staticcheck
 common-staticcheck: $(STATICCHECK)
 	@echo ">> running staticcheck"
-ifeq (,$(wildcard go.mod))
+ifndef GO111MODULE
 	$(STATICCHECK) -ignore "$(STATICCHECK_IGNORE)" $(pkgs)
 else
 	$(STATICCHECK) -ignore "$(STATICCHECK_IGNORE)" -checks "SA*" $(pkgs)
@@ -118,10 +122,11 @@ endif
 
 .PHONY: common-unused
 common-unused: $(GOVENDOR)
-ifeq (,$(wildcard go.mod))
+ifdef GOVENDOR
 	@echo ">> running check for unused packages"
 	@$(GOVENDOR) list +unused | grep . && exit 1 || echo 'No unused packages'
 else
+ifdef GO111MODULE
 	@echo ">> running check for unused/missing packages in go.mod"
 	GO111MODULE=$(GO111MODULE) $(GO) mod tidy
 	@git diff --exit-code -- go.sum go.mod
@@ -131,6 +136,7 @@ ifneq (,$(wildcard vendor))
 	@git diff --exit-code -- go.sum go.mod vendor/
 endif
 endif
+endif
 
 .PHONY: common-build
 common-build: promu
@@ -160,10 +166,10 @@ promu:
 
 .PHONY: $(STATICCHECK)
 $(STATICCHECK):
-ifneq (,$(wildcard go.mod))
-	# Get staticcheck from a temporary directory to avoid modifying the local go.{mod,sum}.
-	# See https://github.com/golang/go/issues/27643.
-	# For now, we are using the next branch of staticcheck because master isn't compatible yet with Go modules.
+ifdef GO111MODULE
+# Get staticcheck from a temporary directory to avoid modifying the local go.{mod,sum}.
+# See https://github.com/golang/go/issues/27643.
+# For now, we are using the next branch of staticcheck because master isn't compatible yet with Go modules.
 	tmpModule=$$(mktemp -d 2>&1) && \
 	mkdir -p $${tmpModule}/staticcheck && \
 	cd "$${tmpModule}"/staticcheck && \
@@ -171,8 +177,10 @@ ifneq (,$(wildcard go.mod))
 	GO111MODULE=on GOOS= GOARCH= $(GO) get -u honnef.co/go/tools/cmd/staticcheck@next && \
 	rm -rf $${tmpModule};
 else
-	GOOS= GOARCH= $(GO) get -u honnef.co/go/tools/cmd/staticcheck
+	GOOS= GOARCH= GO111MODULE=off $(GO) get -u honnef.co/go/tools/cmd/staticcheck
+endif
 
+ifdef GOVENDOR
 .PHONY: $(GOVENDOR)
 $(GOVENDOR):
 	GOOS= GOARCH= $(GO) get -u github.com/kardianos/govendor