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Tsirkin" , Richard Henderson , QEMU Developers , Gerd Hoffmann , Paolo Bonzini , Philippe =?utf-8?Q?Mathieu-Dau?= =?utf-8?Q?d=C3=A9?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Peter Maydell writes: > On Tue, 24 Aug 2021 at 13:05, Markus Armbruster wrote: >> When you know that all callers handle errors like &error_fatal does, use >> of &error_fatal doesn't produce wrong behavior. It's still kind of >> wrong, because relying on such a non-local argument without a genuine >> need is. > > Not using error_fatal results in quite a bit of extra boilerplate > for all those extra explicit "check for failure, print the error > message and exit" points. If the MachineState init function took > an Error** that might be a mild encouragement to "pass an Error > upward rather than exiting"; but it doesn't. > > Right now we have nearly a thousand instances of error_fatal > in the codebase, incidentally. Use of &error_fatal is clearly superior to accomplishing the same behavior the way you describe. My point was this behavior is usually wrong in functions with an Error **errp parameter. When a function is only ever used in contexts where errors are handled the way &error_fatal does, then you can keep things a bit more readable with &error_fatal and without an Error **errp parameter. Nothing wrong with that.