make: nothing can be done for all

Question

I'm trying to run make using the makefile below from my command line. I then receive the following error make: nothing can be done for all . The contents of the makefile are given below.

GENERATED_FILES = \
    dw.js/dw-2.0.js \
    www/static/css/datawrapper.css \
    www/static/css/chart.base.css

all: $(GENERATED_FILES)

clean:
    rm -f -- $(GENERATED_FILES)

dw.js/dw-2.0.js: dw.js/src/*.js
    cd dw.js
    grunt

assets: www/static/css/datawrapper.css www/static/css/chart.base.css

# www/static/js/dw-2.0.js: dw.js/dw-2.0.js
#   @cp dw.js/dw-2.0.js www/static/js/

# www/static/js/dw-2.0.min.js: dw.js/dw-2.0.js
#   @php -r "require 'vendor/autoload.php'; file_put_contents('www/static/js/dw-2.0.min.js', \JShrink\Minifier::minify(file_get_contents('dw.js/dw-2.0.js')));"

messages:
    scripts/update-messages.sh

www/static/css/datawrapper.css: assets/styles/datawrapper/* assets/styles/datawrapper/**/*
    node_modules/.bin/lessc assets/styles/datawrapper/main.less > $@

www/static/css/chart.base.css: assets/styles/chart.base/*
    node_modules/.bin/lessc assets/styles/chart.base/main.less > $@`

Answer 1

What is most likely happening is that the files you're attempting to generate already exist. Why does this prevent the make command from building you're files? It's because of the way make interprets makefiles.

Let's look at a generic makefile rule below and interpret it manually.

target: prerequistes
    actions

make target will check and compare the time-stamp of the file target to the timestamps of all the prerequisite files. If any of the prerequisites have a more recent time-stamp than the target (ie one of the prereqs is "younger"), then actions will be executed.

So, if the prerequisites have already been made and all have the same timestamp has target , then make will write the message make: nothing can be done for target

So, you can do two things. The best thing to do is to ensure that the files you're trying to generate do not exist. Another solution would to run make -B target which will cause make to always make your targets

Please read this question too for reference