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memory allocation failure should print backtrace #147385
Description
When memory allocation fails (for example when extending a Vec), a Rust program prints "memory allocation of xxx bytes failed" and aborts This message would be more helpful if it told you where the allocation happened by printing a backtrace. No backtrace is inconsistent with panics, which print a backtrace. A memory allocation feels like a panic so I expect to get a backtrace.
I understand there might be technical reasons for why this is hard. I'm still reporting this because from a user perspective this is wrong and we might be able to improve it. I didn't find a previous issue talking about this.
Linux, Rust 1.90.0
example program, playground
fn main() {
foo();
}
fn foo() {
// panic!();
let mut v = Vec::new();
v.resize(1000000000000, 1u8);
// Print pointer so vector doesn't get optimized out.
let ptr = v.as_ptr();
println!("{ptr:?}");
}
Activity
workingjubilee commentedon Oct 5, 2025
Well, for one, the backtrace implementation would need to not require allocation.
workingjubilee commentedon Oct 5, 2025
At least, to always succeed. Sometimes that would abort.
Anyways this is actually a duplicate, effectively, of #43596 which you may have found by searching for
oom panicas part of the GH search query, and it doesn't seem to be adding a distinct discussion.Useful comment in a related thread to note: #51245 (comment)
Useful PR to note: #112331