From 8a9b38fd3bbf9d57cddb824f104fad592c7377e0 Mon Sep 17 00:00:00 2001 From: Nicholas Nethercote Date: Tue, 16 May 2023 16:04:03 +1000 Subject: [PATCH] Avoid `&format("...")` calls in error message code. Error message all end up passing into a function as an `impl Into<{D,Subd}iagnosticMessage>`. If an error message is creatd as `&format("...")` that means we allocate a string (in the `format!` call), then take a reference, and then clone (allocating again) the reference to produce the `{D,Subd}iagnosticMessage`, which is silly. This commit removes the leading `&` from a lot of these cases. This means the original `String` is moved into the `{D,Subd}iagnosticMessage`, avoiding the double allocations. This requires changing some function argument types from `&str` to `String` (when all arguments are `String`) or `impl Into<{D,Subd}iagnosticMessage>` (when some arguments are `String` and some are `&str`). --- src/pretty_clif.rs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/pretty_clif.rs b/src/pretty_clif.rs index 27e21183c556..1007b33eca42 100644 --- a/src/pretty_clif.rs +++ b/src/pretty_clif.rs @@ -227,7 +227,7 @@ pub(crate) fn write_ir_file( // Using early_warn as no Session is available here rustc_session::early_warn( rustc_session::config::ErrorOutputType::default(), - &format!("error writing ir file: {}", err), + format!("error writing ir file: {}", err), ); } }