#undefinedbehavior

Live, measured metrics for the hashtag #undefinedbehavior from the open social web. Every number carries a named source and the time it was fetched. Nothing is estimated.

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0
Uses / 7 days
Mastodon
0
Accounts / 7 days
Mastodon
38
Recent posts
Mastodon
~0/hr
Recent pace
Mastodon · last 38
0
Avg reactions / post
Mastodon · last 38

Day-by-day usage

measured · fosstodon.org (Mastodon public tags API) · fetched 2026-07-27 07:06 UTC
0
07-21
0
07-22
0
07-23
0
07-24
0
07-25
0
07-26
0
07-27

0 uses by 0 unique accounts across the window. Real per-day counts, not estimates. Newest bar is today so far.

Related hashtags

measured · fosstodon.org (Mastodon public search API) · fetched 2026-07-27 07:06 UTC

No related tags with measured usage found for #undefinedbehavior.

Live pulse

measured · fosstodon.org (Mastodon tag timeline) · fetched 2026-07-27 07:06 UTC

Everything below is measured over the latest 38 public posts (spanning ~31219 hours).

Posting hours (UTC) — busiest: 16:00

00:0012:0023:00

Languages: English (38)

Avg boosts / post: 0.5

Top of the latest posts

  • @hywan gcc is not wrong though. You need to check upfront with a decent bounds check that what you will do is OK in C, rather than do it, then see if something undefined happened. Unfortunately there weren't good tools in the C or C++ stdli

    aegilops@aegilops♥ 1↻ 02023-02-04 11:09 UTCView post →

  • From the Comp-Cert release notes - sanity in C programming. Someone call ISO and complain. "Constant propagation: optimize "known integer or undefined" results. For example, &x == &x, which is either 1 or undefined, is now replaced by 1" #w

    vy@[email protected]♥ 0↻ 02026-06-03 11:00 UTCView post →

  • 😥: “Everything In C Is Undefined Behavior”, Thomas Habets (https://blog.habets.se/2026/05/Everything-in-C-is-undefined-behavior.html). Via HN: https://news.ycombinator.com/item?id=48203698 On Lobsters: https://lobste.rs/s/dtcfd6/everything

    रञ्जित (Ranjit Mathew)@[email protected]♥ 0↻ 02026-05-24 13:42 UTCView post →

Every number above is measured from a named public API at the shown fetch time. Nothing is estimated or extrapolated. Platforms that lock their data behind paid APIs are not shown. Agents: the same numbers, as JSON, at /api/hashtags/undefinedbehavior