Add c_flags and cxx_flags to env profile settings

CHANGES.md

@@ -93,6 +93,8 @@ unreleased
 - Generate `.merlin` files that account for normal preprocessors defined using a
   subset of the `action` language. (#1768, @rgrinberg)
 
+- Add c_flags and cxx_flags to env profile settings (#1700, @gretay-js)
+
 1.6.2 (05/12/2018)
 ------------------
 

doc/dune-files.rst

@@ -794,6 +794,10 @@ Fields supported in ``<settings>`` are:
 
 - any OCaml flags field, see `OCaml flags`_ for more details.
 
+- ``(c_flags <flags>)`` and ``(cxx_flags <flags>)``
+  to specify compilation flags for C and C++ stubs, respectively.
+  See `library`_ for more details.
+
 - ``(env-vars (<var1> <val1>) .. (<varN> <valN>))``. This will add the
   corresponding variables to the environment in which the build commands are
   executed, and under which ``dune exec`` runs. At the moment, this mechanism is

src/dune_env.ml

@@ -11,6 +11,8 @@ module Stanza = struct
     { flags          : Ordered_set_lang.Unexpanded.t
     ; ocamlc_flags   : Ordered_set_lang.Unexpanded.t
     ; ocamlopt_flags : Ordered_set_lang.Unexpanded.t
+    ; c_flags        : Ordered_set_lang.Unexpanded.t
+    ; cxx_flags      : Ordered_set_lang.Unexpanded.t
     ; env_vars       : Env.t
     ; binaries       : File_bindings.Unexpanded.t
     }
@@ -39,6 +41,10 @@ module Stanza = struct
     let%map flags = field_oslu "flags"
     and ocamlc_flags = field_oslu "ocamlc_flags"
     and ocamlopt_flags = field_oslu "ocamlopt_flags"
+    and c_flags = Ordered_set_lang.Unexpanded.field "c_flags"
+                    ~check:(Syntax.since Stanza.syntax (1, 7))
+    and cxx_flags = Ordered_set_lang.Unexpanded.field "cxx_flags"
+                    ~check:(Syntax.since Stanza.syntax (1, 7))
     and env_vars = env_vars_field
     and binaries = field ~default:File_bindings.empty "binaries"
                      (Syntax.since Stanza.syntax (1, 6)
@@ -47,6 +53,8 @@ module Stanza = struct
     { flags
     ; ocamlc_flags
     ; ocamlopt_flags
+    ; c_flags
+    ; cxx_flags
     ; env_vars
     ; binaries
     }

src/dune_env.mli

@@ -7,6 +7,8 @@ module Stanza : sig
     { flags          : Ordered_set_lang.Unexpanded.t
     ; ocamlc_flags   : Ordered_set_lang.Unexpanded.t
     ; ocamlopt_flags : Ordered_set_lang.Unexpanded.t
+    ; c_flags        : Ordered_set_lang.Unexpanded.t
+    ; cxx_flags      : Ordered_set_lang.Unexpanded.t
     ; env_vars       : Env.t
     ; binaries       : File_bindings.Unexpanded.t
     }

src/env_node.ml

@@ -7,6 +7,8 @@ type t =
   ; config                : Dune_env.Stanza.t option
   ; mutable local_binaries : string File_bindings.t option
   ; mutable ocaml_flags   : Ocaml_flags.t option
+  ; mutable c_flags       : (unit, string list) Build.t option
+  ; mutable cxx_flags     : (unit, string list) Build.t option
   ; mutable external_     : Env.t option
   ; mutable artifacts     : Artifacts.t option
   }
@@ -19,6 +21,8 @@ let make ~dir ~inherit_from ~scope ~config ~env =
   ; scope
   ; config
   ; ocaml_flags = None
+  ; c_flags = None
+  ; cxx_flags = None
   ; external_ = env
   ; artifacts = None
   ; local_binaries = None
@@ -109,3 +113,52 @@ let rec ocaml_flags t ~profile ~expander =
     in
     t.ocaml_flags <- Some flags;
     flags
+
+let rec c_flags t ~profile ~expander ~default_context_flags =
+  match t.c_flags with
+  | Some x -> x
+  | None ->
+    let default =
+      match t.inherit_from with
+      | None -> Build.return default_context_flags
+      | Some (lazy t) -> c_flags t ~profile ~expander ~default_context_flags
+    in
+    let flags =
+      match find_config t ~profile with
+      | None -> default
+      | Some cfg ->
+        let expander = Expander.set_dir expander ~dir:t.dir in
+        let eval = Expander.expand_and_eval_set expander in
+        let f = cfg.c_flags in
+        if  Ordered_set_lang.Unexpanded.has_special_forms f then
+          eval f ~standard:default
+        else
+          eval f ~standard:(Build.return [])
+    in
+    t.c_flags <- Some flags;
+    flags
+
+
+let rec cxx_flags t ~profile ~expander ~default_context_flags =
+  match t.cxx_flags with
+  | Some x -> x
+  | None ->
+    let default =
+      match t.inherit_from with
+      | None -> Build.return default_context_flags
+      | Some (lazy t) -> cxx_flags t ~profile ~expander ~default_context_flags
+    in
+    let flags =
+      match find_config t ~profile with
+      | None -> default
+      | Some cfg ->
+        let expander = Expander.set_dir expander ~dir:t.dir in
+        let eval = Expander.expand_and_eval_set expander in
+        let f = cfg.cxx_flags in
+        if  Ordered_set_lang.Unexpanded.has_special_forms f then
+          eval f ~standard:default
+        else
+          eval f ~standard:(Build.return [])
+    in
+    t.cxx_flags <- Some flags;
+    flags

src/env_node.mli

@@ -19,6 +19,20 @@ val external_ : t -> profile:string -> default:Env.t -> Env.t
 
 val ocaml_flags : t -> profile:string -> expander:Expander.t -> Ocaml_flags.t
 
+val c_flags
+  : t
+  -> profile:string
+  -> expander:Expander.t
+  -> default_context_flags:string list
+  -> (unit, string list) Build.t
+
+val cxx_flags
+  : t
+  -> profile:string
+  -> expander:Expander.t
+  -> default_context_flags:string list
+  -> (unit, string list) Build.t
+
 val local_binaries
   :  t
   -> profile:string

src/expander.ml

@@ -92,7 +92,7 @@ let expand_var_exn t var syn =
         (String_with_vars.Var.describe var))
 
 let make ~scope ~(context : Context.t) ~artifacts
-      ~artifacts_host ~cxx_flags =
+      ~artifacts_host =
   let expand_var ({ bindings; ocaml_config; env = _; scope
                   ; hidden_env = _
                   ; dir = _ ; artifacts = _; expand_var = _
@@ -109,7 +109,7 @@ let make ~scope ~(context : Context.t) ~artifacts
   in
   let ocaml_config = lazy (make_ocaml_config context.ocaml_config) in
   let dir = context.build_dir in
-  let bindings = Pform.Map.create ~context ~cxx_flags in
+  let bindings = Pform.Map.create ~context in
   let env = context.env in
   { dir
   ; hidden_env = Env.Var.Set.empty

src/expander.mli

@@ -20,7 +20,6 @@ val make
   -> context:Context.t
   -> artifacts:Artifacts.t
   -> artifacts_host:Artifacts.t
-  -> cxx_flags:string list
   -> t
 
 val set_env : t -> var:string -> value:string -> t

src/lib_rules.ml

@@ -162,10 +162,10 @@ module Gen (P : Install_rules.Params) = struct
     let cctx = Compilation_context.for_wrapped_compat cctx wrapped_compat in
     Module_compilation.build_modules cctx ~js_of_ocaml ~dynlink ~dep_graphs
 
-  let build_c_file (lib : Library.t) ~expander ~dir ~includes (loc, src, dst) =
+  let build_c_file (lib : Library.t) ~dir ~expander ~includes (loc, src, dst) =
+    let c_flags = SC.c_flags sctx ~dir ~expander ~lib in
     SC.add_rule sctx ~loc ~dir
-      (Expander.expand_and_eval_set expander lib.c_flags
-         ~standard:(Build.return (Context.cc_g ctx))
+      (c_flags
        >>>
        Build.run
          (* We have to execute the rule in the library directory as
@@ -180,25 +180,24 @@ module Gen (P : Install_rules.Params) = struct
          ]);
     dst
 
-  let build_cxx_file (lib : Library.t) ~expander ~dir ~includes (loc, src, dst) =
+  let build_cxx_file (lib : Library.t) ~dir ~expander ~includes (loc, src, dst) =
     let open Arg_spec in
     let output_param =
       if ctx.ccomp_type = "msvc" then
         [Concat ("", [A "/Fo"; Target dst])]
       else
         [A "-o"; Target dst]
     in
+    let cxx_flags = SC.cxx_flags sctx ~dir ~expander ~lib in
     SC.add_rule sctx ~loc ~dir
-      (Expander.expand_and_eval_set expander lib.cxx_flags
-         ~standard:(Build.return (Context.cc_g ctx))
+      (cxx_flags
        >>>
        Build.run
          (* We have to execute the rule in the library directory as
             the .o is produced in the current directory *)
          ~dir:(Path.parent_exn src)
          (SC.resolve_program ~loc:None ~dir sctx ctx.c_compiler)
          ([ S [A "-I"; Path ctx.stdlib_dir]
-          ; As (SC.cxx_flags sctx)
           ; includes
           ; Dyn (fun cxx_flags -> As cxx_flags)
           ] @ output_param @
@@ -288,9 +287,9 @@ module Gen (P : Install_rules.Params) = struct
         ]
     in
     List.map lib.c_names ~f:(fun name ->
-      build_c_file   lib ~expander ~dir ~includes (resolve_name name ~ext:".c")
+      build_c_file   lib ~dir ~expander ~includes (resolve_name name ~ext:".c")
     ) @ List.map lib.cxx_names ~f:(fun name ->
-      build_cxx_file lib ~expander ~dir ~includes (resolve_name name ~ext:".cpp")
+      build_cxx_file lib ~dir ~expander ~includes (resolve_name name ~ext:".cpp")
     )
 
   let build_stubs lib ~dir ~expander ~requires ~dir_contents ~vlib_stubs_o_files =

src/pform.ml

@@ -154,7 +154,7 @@ module Map = struct
       ; "env", since ~version:(1, 4) Macro.Env
       ]
 
-  let create ~(context : Context.t) ~cxx_flags =
+  let create ~(context : Context.t) =
     let ocamlopt =
       match context.ocamlopt with
       | None -> Path.relative context.ocaml_bin "ocamlopt"
@@ -168,6 +168,8 @@ module Map = struct
       | Some p -> path p
     in
     let cflags = context.ocamlc_cflags in
+    let cxx_flags = List.filter context.ocamlc_cflags
+                      ~f:(fun s -> not (String.is_prefix s ~prefix:"-std=")) in
     let strings s = values (Value.L.strings s) in
     let lowercased =
       [ "cpp"            , strings (context.c_compiler :: cflags @ ["-E"])

src/pform.mli

@@ -38,7 +38,7 @@ end
 module Map : sig
   type t
 
-  val create : context:Context.t -> cxx_flags:string list -> t
+  val create : context:Context.t -> t
 
   val superpose : t -> t -> t