Pass command panics to the fallback error handler#24911
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Construct a static `CommandMeta` for each type so they do not take up extra space in the buffer.
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SpecificProtagonist
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Jul 7, 2026
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Looks great; recovering as early as possible when the fallback error handler is set to swallow the panic is the right thing to do.
…field in the `CommandRunner`.
SpecificProtagonist
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urben1680
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Jul 11, 2026
| runner.local_cursor += size_of::<C>(); | ||
| #[cfg(all(feature = "debug", feature = "std"))] | ||
| { | ||
| runner.current_command_name = core::any::type_name::<C>(); |
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I kinda wish DebugName worked like MaybeLocation where it is generic with a good default type but you could change it, like to &'static str in this case.
…ble, but move all the handling code into a `#[cold]` function so that it is not monomorphized.
urben1680
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chescock
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Objective
Improve the handling of commands that panic.
Currently, if a command panics, any unapplied commands are left in the command queue. This means they will get run, but at an unpredictable time in the future.
And when running in
no_std, cleanup is not run at all and the commands simply leak.Solution
Catch panics from commands and pass them to the fallback error handler, just as we now do for systems from #24240. This means if the error handler is set to something non-panicking like
warn, thenflush_commands()will never panic and all commands in the queue will be applied.Introduce a RAII guard during command application that will drop any commands still in the queue and perform cleanup during unwinding, even on
no_std.To make the command's type name available in the error handler, add a field to the RAII guard that gets written by
consume_command_and_get_sizebefore applying the command.