Bug 233250

Summary:	Porter's handbook: Undocumented OPT_USE variable
Product:	Documentation	Reporter:	Lorenzo Salvadore <salvadore>
Component:	Books & Articles	Assignee:	freebsd-doc (Nobody) <doc>
Status:	Closed Not A Bug
Severity:	Affects Only Me
Priority:	---
Version:	Latest
Hardware:	Any
OS:	Any

Description Lorenzo Salvadore freebsd_committer

2018-11-16 09:13:36 UTC

It seems the OPT_USE variable (where OPT stands for any option name) seems to be undocumented. In particular, it is not listed in "5.13.3.11. Generic Variables Replacement, OPT_VARIABLE and OPT_VARIABLE_OFF" (see https://www.freebsd.org/doc/en/books/porters-handbook/makefile-options.html ), although OPT_USES is different.

For an example of use, here is the bug report where I discovered it's existence: bug #233240.

Comment 1 Lorenzo Salvadore freebsd_committer

2018-11-16 09:22:39 UTC

Sorry I have written badly about the difference USE/USES, I will explain better.

OPT_USES is in the list, but OPT_USE is not. The two variables are different and have different behaviors. My guess is (but someone should confirm it) that OPT_USE= A=B adds USE_A= B conditionally depending on the state of OPT.

If someone confirms I can try to write a first draft.

Comment 2 Tobias Kortkamp freebsd_committer

2018-11-16 11:00:18 UTC

(In reply to Lorenzo Salvadore from comment #1)
It is already documented here:

https://www.freebsd.org/doc/en/books/porters-handbook/makefile-options.html#options-use

Comment 3 Lorenzo Salvadore freebsd_committer

2018-11-16 11:19:50 UTC

Thanks, I had not seen it.