rust-lang/rust-analyzer · error

invalid profile depth

Error message

invalid profile depth

What it means

The hprof WriteFilter spec parser expects an optional '@N' suffix giving maximum profiling depth, parsed as usize. If the text after '@' is not a valid usize the expect panics with 'invalid profile depth'. Like the longer_than check, this is upfront validation of the profiling filter string.

Source

Thrown at crates/rust-analyzer/src/tracing/hprof.rs:243

#[derive(Default, Clone, Debug)]
pub(crate) struct WriteFilter {
    depth: usize,
    longer_than: Duration,
}

impl WriteFilter {
    pub(crate) fn from_spec(mut spec: &str) -> (WriteFilter, Option<FxHashSet<String>>) {
        let longer_than = if let Some(idx) = spec.rfind('>') {
            let longer_than = spec[idx + 1..].parse().expect("invalid profile longer_than");
            spec = &spec[..idx];
            Duration::from_millis(longer_than)
        } else {
            Duration::new(0, 0)
        };

        let depth = if let Some(idx) = spec.rfind('@') {
            let depth: usize = spec[idx + 1..].parse().expect("invalid profile depth");
            spec = &spec[..idx];
            depth
        } else {
            999
        };
        let allowed = if spec == "*" {
            None
        } else {
            Some(FxHashSet::from_iter(spec.split('|').map(String::from)))
        };
        (WriteFilter { depth, longer_than }, allowed)
    }
}

#[allow(non_camel_case_types)]
struct ms(Duration);

impl std::fmt::Display for ms {

View on GitHub (pinned to e8f7e90aa3)

Solutions

1. Fix the spec so the '@' suffix is a valid depth integer, e.g. 'profile@3' limits depth to 3.
2. Remove the '@' suffix entirely to use the default depth of 999.
3. Check the env var for shell-quoting/interpolation issues that corrupt the value.

Example fix

// before
RA_PROFILE="load@"          // empty depth
// after
RA_PROFILE="load@5"         // depth 5, or omit '@' for default

fn validate_profile_depth(spec: &str) -> Result<(), String> {
    if let Some(idx) = spec.rfind('@') {
        spec[idx + 1..].parse::<usize>()
            .map(|_| ())
            .map_err(|_| format!("invalid depth suffix in {spec:?}"))
    } else { Ok(()) }
}

When it happens

Trigger: Passing a profiling spec such as 'profile@x' or 'profile@' (empty after '@'), or a value exceeding usize range (e.g. '@99999999999999999999999'), through the profiling env/config.

Common situations: Typos in the depth portion of RA_PROFILE; shell interpolation replacing the number with empty or garbage; docs confusion between spec sections ('@' for depth vs '>' for duration).

Related errors

• invalid profile longer_than
• Memory profiling is not enabled for this build of rust-analy
• Please set `rust-analyzer.profiling.memoryProfile` to the pa
• Unable to serialize data
• Unable to write data

AI-assisted analysis of rust-lang/rust-analyzer@e8f7e90aa3 (2026-09-03). Data as JSON: /api/errors/025a03c5f6acce10. Report an issue: GitHub.