Add a way to pass the context CFLAGS to foreign build sandboxing

[samoht]

Hi there,

I am trying to compile some C code, using the foreign build sandboxing. This is working nicely, but now I would like to be able to tweak the C flags (for instance to use the ones defined in the current workspace context).

Is there a way to do that properly?

I've tried various things, but I only succeeded to make dune explode:

$ echo dune
(rule
  (target foo)
  (action (setenv X %{c_flags} (run echo 1))))
$ dune build ./foo
Error: exception { exn =
    ("Pform.Map.expand_exn",
    { t =
        { vars =
            map
              { "-verbose" : No_info Values []
              ; "<" :
                  Deleted_in
                    "First_dep",(1, 0),[ "Use a named dependency instead:\n\
                                          \n\
                                         \  (deps (:x <dep>) ...)\n\
                                         \   ... %{x}\n\
                                          ..."
                                       ]
[...]

Same for:

(rule
  (target foo)
  (action (run echo %{c_flags})))

Or with (with is what I wanted to use to pass %{c_flags} to the sandboxed ./configure script):

(rule
  (target foo)
  (action (bash "echo %{c_flags}")))

[rgrinberg]

Just to clarify, you'd like to print the c_flags so that some script can process them?

[samoht]

Just to clarify, you'd like to print the c_flags so that some script can process them?

Yes. I found a way by printing %{cc} and removing the first word, so it's not blocking (just a bit surprising that it failed like that).

[snowleopard]

@samoht Thanks for reporting! I can look into this issue but probably not this/next week.

[dibrinsofor]

Any luck with this?

[snowleopard]

I'm not aware of anyone working on this at the moment. (Alas, I never found time to look.)