gazagnaire.org
Typed runtime_events probes for OCaml
probe: js stubs for the no-ring runtime
Fulfil the probe.mli no-ring contract under js_of_ocaml: the ring
reports inactive, the ring write fails hard (unreachable while the
ring is inactive), and the minor-words counter reads zero, so span
allocation deltas are zero rather than a trap. Emission flows through
set_sink, which needs no C support.
Makes the committed test/js spec test pass; a browser consumer linking
probe no longer dies with a missing-primitive TypeError at its first
span enter.
author
Thomas Gazagnaire
date
(Jul 22, 2026, 10:26 PM -0700)
commit
77dcafa1
77dcafa10365ed4eef084a67d29eec1028032030
parent
4b73fedc
4b73fedc91a20aa647fc121eac58e323e86f1a82
+29
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lib/dune
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lib/dune
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lib/probe_stubs.js
+26
lib/probe_stubs.js
···
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/*---------------------------------------------------------------------------
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Copyright (c) 2026 Thomas Gazagnaire. All rights reserved.
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SPDX-License-Identifier: MIT
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---------------------------------------------------------------------------*/
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/* js_of_ocaml counterparts of probe_stubs.c. There is no runtime_events ring
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under js, so the ring is never active, ring writes are unreachable, and the
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minor-heap allocation counter reads as zero. Emission flows through
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Probe.set_sink instead (see probe.mli). */
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//Provides: probe_runtime_events_are_active
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function probe_runtime_events_are_active(unit) {
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return 0; /* no runtime_events ring under js */
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}
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//Provides: probe_runtime_events_user_write
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//Requires: caml_failwith
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function probe_runtime_events_user_write(write_buffer, event, event_content) {
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/* Unreachable while the ring reports inactive; fail hard if reached. */
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caml_failwith("probe_runtime_events_user_write: no runtime_events ring under js");
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}
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//Provides: probe_minor_words
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function probe_minor_words(unit) {
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return 0; /* no minor-heap counter under js */
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}