[misc] Better preserve backtraces in several modules

Re-raising inside exception handlers must be done with care in order
to preserve backtraces; even if newer OCaml versions do a better job
in automatically spilling `%reraise` in places that matter, there is
no guarantee for that to happen.

I've done a best-effort pass of places that were re-raising
incorrectly, hopefully I got the logic right.

There is the special case of `Nametab.error_global_not_found` which is
raised many times in response to a `Not_found` error; IMHO this error
should be converted to something more specific, however the scope of
that change would be huge as to do easily...

1 files changed, 5 insertions, 2 deletions

diff --git a/kernel/cbytegen.ml b/kernel/cbytegen.ml
index 050f986367..b3a4bd7471 100644
--- a/kernel/cbytegen.ml
+++ b/kernel/cbytegen.ml
@@ -874,8 +874,11 @@ let compile ~fail_on_error ?universes:(universes=0) env c =
     (if !dump_bytecode then
       Feedback.msg_debug (dump_bytecodes init_code !fun_code fv)) ;
     Some (init_code,!fun_code, Array.of_list fv)
-  with TooLargeInductive msg ->
-    let fn = if fail_on_error then CErrors.user_err ?loc:None ~hdr:"compile" else
+  with TooLargeInductive msg as exn ->
+    let _, info = Exninfo.capture exn in
+    let fn = if fail_on_error then
+        CErrors.user_err ?loc:None ~info ~hdr:"compile"
+      else
         (fun x -> Feedback.msg_warning x) in
     fn msg; None