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Always register a tracing subscriber, even if no env var is set #89623

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Always register a tracing subscriber, even if no env var is set #89623

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6 changes: 0 additions & 6 deletions compiler/rustc_driver/src/lib.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -1253,12 +1253,6 @@ pub fn init_rustc_env_logger() {
/// tracing crate version. In contrast to `init_rustc_env_logger` it allows you to choose an env var
/// other than `RUSTC_LOG`.
pub fn init_env_logger(env: &str) {
// Don't register a dispatcher if there's no filter to print anything
match std::env::var(env) {
Err(_) => return,
Ok(s) if s.is_empty() => return,
Ok(_) => {}
}
Comment on lines -1256 to -1261
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if we wanted to have a way to completely disable logging, we could consider special-casing RUSTC_LOG=off, instead of "no value", but, since the perf run indicates that the performance difference between "no subscriber" and "levels disabled" is negligable, it's probably not worth messing with...

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it may be more noticeable if debug assertions are turned on, but I have to test that locally. Since I often run with RUSTC_LOG and without, and don't notice something, it can't be too bad though.

let color_logs = match std::env::var(String::from(env) + "_COLOR") {
Ok(value) => match value.as_ref() {
"always" => true,
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