Allow first character of OCAMLPARAM to specify an alternative separator

The alternative separator must be in ":|; ,".

4 files changed, 36 insertions, 9 deletions

diff --git a/Changes b/Changes
index 6f349eed2d..afb82c5f78 100644
--- a/Changes
+++ b/Changes
@@ -14,6 +14,10 @@ be mentioned in the 4.06 section below instead of here.)
 
 ### Compiler user-interface and warnings:
 
+- GPR#1166: In OCAMLPARAM, an alternative separator can be specified as
+  first character (instead of comma) in the set ":|; ,"
+  (Fabrice Le Fessant)
+
 ### Runtime system:
 
 ### Other libraries:
diff --git a/driver/compenv.ml b/driver/compenv.ml
index 194fa617c8..2909d67e7d 100644
--- a/driver/compenv.ml
+++ b/driver/compenv.ml
@@ -101,19 +101,30 @@ type filename = string
 type readenv_position =
   Before_args | Before_compile of filename | Before_link
 
-(* Syntax of OCAMLPARAM: (name=VALUE,)* _ (,name=VALUE)*
-   where VALUE should not contain ',' *)
+(* Syntax of OCAMLPARAM: SEP?(name=VALUE SEP)* _ (SEP name=VALUE)*
+   where VALUE should not contain SEP, and SEP is ',' if unspecified,
+   or ':', '|', ';', ' ' or ',' *)
 exception SyntaxError of string
 
 let parse_args s =
-  let args = String.split_on_char ',' s in
+  let args =
+    let len = String.length s in
+    if len = 0 then []
+    else
+      (* allow first char to specify an alternative separator in ":|; ," *)
+      match s.[0] with
+      | ( ':' | '|' | ';' | ' ' | ',' ) as c ->
+         List.tl (String.split_on_char c s)
+      | _ -> String.split_on_char ',' s
+  in
   let rec iter is_after args before after =
     match args with
       [] ->
       if not is_after then
         raise (SyntaxError "no '_' separator found")
       else
-      (List.rev before, List.rev after)
+        (List.rev before, List.rev after)
+    | "" :: tail -> iter is_after tail before after
     | "_" :: _ when is_after -> raise (SyntaxError "too many '_' separators")
     | "_" :: tail -> iter true tail before after
     | arg :: tail ->
@@ -358,7 +369,9 @@ let read_one_param ppf position name v =
         ccobjs := Misc.rev_split_words v @ !ccobjs
     end
 
-  | "ccopts" ->
+  | "ccopt"
+  | "ccopts"
+    ->
     begin
       match position with
       | Before_link | Before_compile _ ->
diff --git a/manual/manual/cmds/comp.etex b/manual/manual/cmds/comp.etex
index fc1ef28f17..3e60101408 100644
--- a/manual/manual/cmds/comp.etex
+++ b/manual/manual/cmds/comp.etex
@@ -122,8 +122,13 @@ development work, not in released packages.
 
 \begin{options}
 \item["OCAMLPARAM" \rm(environment variable)]
-Arguments that will be inserted before or after the arguments from the
-command line.
+A set of arguments that will be inserted before or after the arguments from
+the command line. Arguments are specified in a comma-separated list
+of "name=value" pairs. A "_" is used to specify the position of
+the command line arguments, i.e. "a=x,_,b=y" means that "a=x" should be
+executed before parsing the arguments, and "b=y" after. Finally,
+an alternative separator can be specified as the
+first character of the string, within the set ":|; ,".
 \item["ocaml_compiler_internal_params" \rm(file in the stdlib directory)]
 A mapping of file names to lists of arguments that
 will be added to the command line (and "OCAMLPARAM") arguments.
diff --git a/manual/manual/cmds/native.etex b/manual/manual/cmds/native.etex
index 1e846849ca..2351b55723 100644
--- a/manual/manual/cmds/native.etex
+++ b/manual/manual/cmds/native.etex
@@ -135,8 +135,13 @@ development work, not in released packages.
 
 \begin{options}
 \item["OCAMLPARAM" \rm(environment variable)]
-Arguments that will be inserted before or after the arguments from the
-command line.
+A set of arguments that will be inserted before or after the arguments from
+the command line. Arguments are specified in a comma-separated list
+of "name=value" pairs. A "_" is used to specify the position of
+the command line arguments, i.e. "a=x,_,b=y" means that "a=x" should be
+executed before parsing the arguments, and "b=y" after. Finally,
+an alternative separator can be specified as the
+first character of the string, within the set ":|; ,".
 \item["ocaml_compiler_internal_params" \rm(file in the stdlib directory)]
 A mapping of file names to lists of arguments that
 will be added to the command line (and "OCAMLPARAM") arguments.