Makefile check if folder and/or file exists - makefile

Question

I have the following Makefile:
build: clean
${GOPATH}/bin/dep ensure
env GOOS=linux go build -o ./bin/status ./lib/status/main.go
elm-app build
init:
${GOPATH}/bin/dep init -v
test:
env GOOS=linux go test -v ./lib/status
strip:
strip ./bin/status
clean:
if [ -f ./bin/status ]; then
rm -f ./bin/status
fi
but I get
if [ -f ./bin/status ]; then
/bin/sh: 1: Syntax error: end of file unexpected
Makefile:16: recipe for target 'clean' failed
make: *** [clean] Error 2
what am i missing?
any advice is much appreciated

Answer 1

Each line of a makefile is run in a separate shell. This means your rule here:
clean:
if [ -f ./bin/status ]; then
rm -f ./bin/status
fi
actually runs the following commands:
/bin/sh -c "if [ -f ./bin/status ]; then"
/bin/sh -c "rm -f ./bin/status"
/bin/sh -c "fi"
You can see why you get this message. To ensure that all lines are send into a single shell you need to use backslashes to continue the lines like this:
clean:
if [ -f ./bin/status ]; then \
rm -f ./bin/status; \
fi
Note this means you also need a semicolon after the rm command so separate it from the ending fi.
Now you get a shell invocation like this:
/bin/sh -c "if [ -f ./bin/status ]; then \
rm -f ./bin/status; \
fi"