|
|
# Idiom: Directories
|
|
|
|
|
|
|
|
|
In order to create directories, we use "order-only" make dependencies, e.g.
|
|
|
|
|
|
```wiki
|
|
|
build/foo.o : foo.c foo.h | $$(dir $$@)/.
|
|
|
gcc $< -o $@
|
|
|
```
|
|
|
|
|
|
|
|
|
Dependencies after the `|` are order-only, i.e. we only require that the directory exists, not that `build/foo.o` is newer than it. The doubled-dollars are because this needs to happen during the second-expansion phase, as $@ is not available during the first-expansion. |