[makefile] rule with spaces

[whired123]

$ cat makefile
default: "a b"

$ touch "a b"

$ make
make: *** No rule to make target '"a', needed by 'default'.  Stop.

Why?

 

[dos2unix]

Make sees a and b and two separate targets. Double quotes work a little differently in makefiles.

try this...

default: a\ b

a\ b:
    touch "a b"

Or this...

FILE = a\ b
default: $(FILE)
$(FILE):
    touch "a b"

 

[whired123]

Make sees a and b and two separate targets. Double quotes work a little differently in makefiles.

try this...

default: a\ b

a\ b:
    touch "a b"

Or this...

FILE = a\ b
default: $(FILE)
$(FILE):
    touch "a b"

OK, but

$ tree
├── a b
└── makefile

$ cat makefile
spaces := $(shell echo "a b")
default: $(spaces)

$ make
make: *** No rule to make target 'a', needed by 'default'.  Stop.

 

[dos2unix]

spaces := $(shell echo "a b")

That won't work in a makefile. make is not bash, it handles double quotes differently.
As long as you keep doing this, it will fail.