draft: compile flags feature

src/dune/cinaps.ml

@@ -9,6 +9,7 @@ type t =
   ; preprocess : Preprocess.Without_instrumentation.t Preprocess.Per_module.t
   ; preprocessor_deps : Dep_conf.t list
   ; flags : Ocaml_flags.Spec.t
+  ; compile_flags : Ocaml_flags.Spec.t
   }
 
 let name = "cinaps"
@@ -32,8 +33,9 @@ let decode =
        field "libraries"
          (Dune_file.Lib_deps.decode ~allow_re_export:false)
          ~default:[]
-     and+ flags = Ocaml_flags.Spec.decode in
-     { loc; files; libraries; preprocess; preprocessor_deps; flags })
+     and+ flags = Ocaml_flags.Spec.decode 
+     and+ compile_flags =Ocaml_flags.Spec.decode in
+     { loc; files; libraries; preprocess; preprocessor_deps; flags; compile_flags })
 
 let () =
   let open Dune_lang.Decoder in
@@ -100,6 +102,7 @@ let gen_rules sctx t ~dir ~scope =
       ~requires_compile:(Lib.Compile.direct_requires compile_info)
       ~requires_link:(Lib.Compile.requires_link compile_info)
       ~flags:(Ocaml_flags.of_list [ "-w"; "-24" ])
+      ~compile_flags:(Ocaml_flags.of_list [ "-w"; "-24" ])
       ~js_of_ocaml:None ~dynlink:false ~package:None
   in
   Exe.build_and_link cctx

src/dune/compilation_context.ml

@@ -56,6 +56,7 @@ type t =
   ; obj_dir : Path.Build.t Obj_dir.t
   ; modules : Modules.t
   ; flags : Ocaml_flags.t
+  ; compile_flags : Ocaml_flags.t
   ; requires_compile : Lib.t list Or_exn.t
   ; requires_link : Lib.t list Or_exn.t Lazy.t
   ; includes : Includes.t
@@ -84,6 +85,8 @@ let modules t = t.modules
 
 let flags t = t.flags
 
+let compile_flags t = t.compile_flags
+
 let requires_compile t = t.requires_compile
 
 let requires_link t = Lazy.force t.requires_link
@@ -110,7 +113,7 @@ let modes t = t.modes
 
 let context t = Super_context.context t.super_context
 
-let create ~super_context ~scope ~expander ~obj_dir ~modules ~flags
+let create ~super_context ~scope ~expander ~obj_dir ~modules ~flags ~compile_flags
     ~requires_compile ~requires_link ?(preprocessing = Preprocessing.dummy)
     ~opaque ?stdlib ~js_of_ocaml ~dynlink ~package ?vimpl ?modes () =
   let requires_compile =
@@ -139,6 +142,7 @@ let create ~super_context ~scope ~expander ~obj_dir ~modules ~flags
   ; obj_dir
   ; modules
   ; flags
+  ; compile_flags
   ; requires_compile
   ; requires_link
   ; includes = Includes.make ~opaque ~requires:requires_compile
@@ -159,6 +163,11 @@ let for_alias_module t =
     let dune_version = Dune_project.dune_version project in
     Ocaml_flags.default ~profile:(SC.profile t.super_context) ~dune_version
   in
+  let compile_flags =
+    let project = Scope.project t.scope in
+    let dune_version = Dune_project.dune_version project in
+    Ocaml_flags.default ~profile:(SC.profile t.super_context) ~dune_version
+  in
   let sandbox =
     let ctx = Super_context.context t.super_context in
     (* If the compiler reads the cmi for module alias even with [-w -49
@@ -173,6 +182,9 @@ let for_alias_module t =
     flags =
       Ocaml_flags.append_common flags
         [ "-w"; "-49"; "-nopervasives"; "-nostdlib" ]
+  ; compile_flags =
+      Ocaml_flags.append_common compile_flags
+        [ "-w"; "-49"; "-nopervasives"; "-nostdlib" ]
   ; includes = Includes.empty
   ; stdlib = None
   ; sandbox

src/dune/compilation_context.mli

@@ -28,6 +28,7 @@ val create :
   -> obj_dir:Path.Build.t Obj_dir.t
   -> modules:Modules.t
   -> flags:Ocaml_flags.t
+  -> compile_flags:Ocaml_flags.t
   -> requires_compile:Lib.t list Or_exn.t
   -> requires_link:Lib.t list Or_exn.t Lazy.t
   -> ?preprocessing:Preprocessing.t
@@ -60,6 +61,8 @@ val modules : t -> Modules.t
 
 val flags : t -> Ocaml_flags.t
 
+val compile_flags : t -> Ocaml_flags.t
+
 val requires_link : t -> Lib.t list Or_exn.t
 
 val requires_compile : t -> Lib.t list Or_exn.t

src/dune/exe_rules.ml

@@ -87,6 +87,7 @@ let executables_rules ~sctx ~dir ~expander ~dir_contents ~scope ~compile_info
       l
   in
   let flags = SC.ocaml_flags sctx ~dir exes.buildable.flags in
+  let compile_flags = SC.ocaml_flags sctx ~dir exes.buildable.flags in
   let link_deps = Dep_conf_eval.unnamed ~expander exes.link_deps in
   let foreign_archives = exes.buildable.foreign_archives |> List.map ~f:snd in
   let link_flags =
@@ -129,8 +130,9 @@ let executables_rules ~sctx ~dir ~expander ~dir_contents ~scope ~compile_info
              | _ -> false)
     in
     Compilation_context.create () ~super_context:sctx ~expander ~scope ~obj_dir
-      ~modules ~flags ~requires_link ~requires_compile ~preprocessing:pp
-      ~js_of_ocaml ~opaque:Inherit_from_settings ~dynlink ~package:exes.package
+      ~modules ~flags ~compile_flags ~requires_link ~requires_compile
+      ~preprocessing:pp ~js_of_ocaml ~opaque:Inherit_from_settings ~dynlink
+      ~package:exes.package
   in
   let o_files =
     if not (Executables.has_foreign exes) then
@@ -172,7 +174,7 @@ let executables_rules ~sctx ~dir ~expander ~dir_contents ~scope ~compile_info
   Exe.build_and_link_many cctx ~programs ~linkages ~link_args ~o_files
     ~promote:exes.promote ~embed_in_plugin_libraries;
   ( cctx
-  , Merlin.make () ~requires:requires_compile ~flags ~modules
+  , Merlin.make () ~requires:requires_compile ~flags ~modules ~compile_flags
       ~preprocess:(Preprocess.Per_module.single_preprocess preprocess)
       ~obj_dir )
 

src/dune/inline_tests.ml

@@ -283,9 +283,11 @@ include Sub_system.Register_end_point (struct
         ~obj_dir ~modules ~opaque:(Explicit false) ~requires_compile:runner_libs
         ~requires_link:(lazy runner_libs)
         ~flags:
-          (Ocaml_flags.append_common
-             (Super_context.ocaml_flags sctx ~dir lib.buildable.flags)
-             [ "-w"; "-24"; "-g" ])
+        (Ocaml_flags.of_list [ "-w"; "-24"; "-g" ])
+        ~compile_flags:
+        (Ocaml_flags.append_common
+           (Super_context.ocaml_flags sctx ~dir lib.buildable.flags)
+           [ "-w"; "-24"; "-g" ])
         ~js_of_ocaml:(Some lib.buildable.js_of_ocaml) ~dynlink:false
         ~package:(Option.map lib.public ~f:Dune_file.Public_lib.package)
     in

src/dune/lib_rules.ml

@@ -338,6 +338,7 @@ let cctx (lib : Library.t) ~sctx ~source_modules ~dir ~expander ~scope
       Required
   in
   let flags = Super_context.ocaml_flags sctx ~dir lib.buildable.flags in
+  let compile_flags = Super_context.ocaml_flags sctx ~dir lib.buildable.flags in
   let obj_dir = Library.obj_dir ~dir lib in
   let vimpl = Virtual_rules.impl sctx ~lib ~scope in
   let ctx = Super_context.context sctx in
@@ -371,7 +372,7 @@ let cctx (lib : Library.t) ~sctx ~source_modules ~dir ~expander ~scope
     ~opaque:Inherit_from_settings ~js_of_ocaml:(Some lib.buildable.js_of_ocaml)
     ~dynlink ?stdlib:lib.stdlib
     ~package:(Option.map lib.public ~f:Dune_file.Public_lib.package)
-    ?vimpl ~modes
+    ?vimpl ~modes ~compile_flags
 
 let library_rules (lib : Library.t) ~cctx ~source_modules ~dir_contents
     ~compile_info =
@@ -383,6 +384,7 @@ let library_rules (lib : Library.t) ~cctx ~source_modules ~dir_contents
   let obj_dir = Compilation_context.obj_dir cctx in
   let vimpl = Compilation_context.vimpl cctx in
   let flags = Compilation_context.flags cctx in
+  let compile_flags = Compilation_context.compile_flags cctx in
   let sctx = Compilation_context.super_context cctx in
   let dir = Compilation_context.dir cctx in
   let scope = Compilation_context.scope cctx in
@@ -416,7 +418,7 @@ let library_rules (lib : Library.t) ~cctx ~source_modules ~dir_contents
     ; compile_info
     };
   ( cctx
-  , Merlin.make () ~requires:requires_compile ~flags ~modules
+  , Merlin.make () ~requires:requires_compile ~flags  ~compile_flags ~modules
       ~preprocess:(Preprocess.Per_module.single_preprocess preprocess)
       ~libname:(snd lib.name) ~obj_dir )
 

src/dune/merlin.ml

@@ -95,13 +95,15 @@ end
 type t =
   { requires : Lib.Set.t
   ; flags : string list Build.t
+  ; compile_flags : string list Build.t
   ; preprocess : Preprocess.Without_instrumentation.t Preprocess.t
   ; libname : Lib_name.Local.t option
   ; source_dirs : Path.Source.Set.t
   ; objs_dirs : Path.Set.t
   }
 
-let make ?(requires = Ok []) ~flags ?(preprocess = Preprocess.No_preprocessing)
+let make ?(requires = Ok []) ~flags ~compile_flags
+    ?(preprocess = Preprocess.No_preprocessing)
     ?libname ?(source_dirs = Path.Source.Set.empty) ~modules ~obj_dir () =
   (* Merlin shouldn't cause the build to fail, so we just ignore errors *)
   let requires =
@@ -121,8 +123,18 @@ let make ?(requires = Ok []) ~flags ?(preprocess = Preprocess.No_preprocessing)
         flags
       |> Ocaml_flags.common
   in
+  let compile_flags =
+    match Modules.alias_module modules with
+    | None -> Ocaml_flags.common compile_flags
+    | Some m ->
+      Ocaml_flags.prepend_common
+        [ "-open"; Module_name.to_string (Module.name m) ]
+        compile_flags
+      |> Ocaml_flags.common
+  in
   { requires
   ; flags = Build.catch flags ~on_error:(fun _ -> [])
+  ; compile_flags = Build.catch compile_flags ~on_error:(fun _ -> [])
   ; preprocess
   ; libname
   ; source_dirs
@@ -267,6 +279,10 @@ let merge_two ~allow_approx_merlin a b =
       (let+ a = a.flags
        and+ b = b.flags in
        a @ b)
+  ; compile_flags =
+  (let+ a = a.compile_flags
+  and+ b = b.compile_flags in
+  a @ b)
   ; preprocess = Pp.merge ~allow_approx_merlin a.preprocess b.preprocess
   ; libname =
       ( match a.libname with

src/dune/merlin.mli

@@ -8,6 +8,7 @@ type t
 val make :
      ?requires:Lib.t list Or_exn.t
   -> flags:Ocaml_flags.t
+  -> compile_flags:Ocaml_flags.t
   -> ?preprocess:Preprocess.Without_instrumentation.t Preprocess.t
   -> ?libname:Lib_name.Local.t
   -> ?source_dirs:Path.Source.Set.t

src/dune/toplevel.ml

@@ -174,10 +174,16 @@ module Stanza = struct
         (Ocaml_flags.default ~dune_version ~profile)
         [ "-w"; "-24" ]
     in
+    let compile_flags =
+      let profile = Super_context.profile sctx in
+      Ocaml_flags.append_common
+        (Ocaml_flags.default ~dune_version ~profile)
+        [ "-w"; "-24" ]
+    in
     let cctx =
       Compilation_context.create () ~super_context:sctx ~scope ~obj_dir
         ~expander
-        ~modules:(Source.modules source preprocessing)
+        ~modules:(Source.modules source preprocessing) ~compile_flags
         ~opaque:(Explicit false) ~requires_compile ~requires_link ~flags
         ~js_of_ocaml:None ~dynlink:false ~package:None ~preprocessing
     in

src/dune/utop.ml

@@ -109,9 +109,16 @@ let setup sctx ~dir =
       (Ocaml_flags.default ~dune_version ~profile:(Super_context.profile sctx))
       [ "-w"; "-24" ]
   in
+  let compile_flags =
+    let project = Scope.project scope in
+    let dune_version = Dune_project.dune_version project in
+    Ocaml_flags.append_common
+      (Ocaml_flags.default ~dune_version ~profile:(Super_context.profile sctx))
+      [ "-w"; "-24" ]
+  in
   let cctx =
     Compilation_context.create () ~super_context:sctx ~expander ~scope ~obj_dir
-      ~modules ~opaque:(Explicit false)
+      ~modules ~opaque:(Explicit false) ~compile_flags
       ~requires_link:(lazy requires)
       ~requires_compile:requires ~flags ~js_of_ocaml:None ~dynlink:false
       ~package:None ~preprocessing

test/blackbox-tests/dune.inc

@@ -1602,6 +1602,17 @@
    test-cases/incremental-rebuilds.t
    (progn (run dune-cram run run.t) (diff? run.t run.t.corrected)))))
 
+(rule
+ (alias inline_tests-compile-flags)
+ (deps
+  (package dune)
+  (source_tree test-cases/inline_tests/compile-flags.t)
+  (alias test-deps))
+ (action
+  (chdir
+   test-cases/inline_tests/compile-flags.t
+   (progn (run dune-cram run run.t) (diff? run.t run.t.corrected)))))
+
 (rule
  (alias inline_tests-dune-file)
  (deps
@@ -3347,6 +3358,7 @@
   (alias include-loop)
   (alias include-qualified)
   (alias incremental-rebuilds)
+  (alias inline_tests-compile-flags)
   (alias inline_tests-dune-file)
   (alias inline_tests-many-backends-choose)
   (alias inline_tests-missing-backend)
@@ -3647,6 +3659,7 @@
   (alias include-loop)
   (alias include-qualified)
   (alias incremental-rebuilds)
+  (alias inline_tests-compile-flags)
   (alias inline_tests-dune-file)
   (alias inline_tests-many-backends-choose)
   (alias inline_tests-missing-backend)

test/blackbox-tests/test-cases/inline_tests/compile-flags.t/run.t

@@ -0,0 +1,20 @@
+  $ cat >dune-project <<EOF
+  > (lang dune 2.7)
+  > EOF
+  $ cat >dune <<EOF
+  > (library
+  >  (name backend_foo)
+  >  (modules ())
+  >  (inline_tests.backend
+  >   (generate_runner (echo "let () = print_endline \"backend_foo\""))))
+  > 
+  > (library
+  >   (name compile_flags_test)
+  >   (inline_tests
+  >     (backend backend_foo)
+  >     (compile_flags -flag-that-is-not-accepted-by-ocaml)))
+  > EOF
+
+  $ dune runtest
+  inline_test_runner_compile_flags_test alias runtest
+  backend_foo

test/blackbox-tests/test-cases/inline_tests/dune-file.t/run.t

@@ -30,10 +30,3 @@ package:
   Entering directory 'dune-file-user'
   inline_test_runner_foo_tests alias runtest
   414243
-
-We run the inline tests with a program that passes in specifc compile flags:
-
-  $ export OCAMLPATH=$PWD/_install/lib; dune runtest --root dune-file-compile-flags
-  Entering directory 'dune-file-compile-flags'
-  inline_test_runner_compile_flags_test alias runtest
-  414243