diff --git a/compiler/rustc_lint/src/context.rs b/compiler/rustc_lint/src/context.rs index d1d4bb37528..972240f42cf 100644 --- a/compiler/rustc_lint/src/context.rs +++ b/compiler/rustc_lint/src/context.rs @@ -837,9 +837,17 @@ fn lookup_with_diagnostics( (use_span, "'_".to_owned()) }; debug!(?deletion_span, ?use_span); + + // issue 107998 for the case such as a wrong function pointer type + // `deletion_span` is empty and there is no need to report lifetime uses here + let suggestions = if deletion_span.is_empty() { + vec![(use_span, replace_lt)] + } else { + vec![(deletion_span, String::new()), (use_span, replace_lt)] + }; db.multipart_suggestion( msg, - vec![(deletion_span, String::new()), (use_span, replace_lt)], + suggestions, Applicability::MachineApplicable, ); } diff --git a/tests/ui/single-use-lifetime/issue-107998.rs b/tests/ui/single-use-lifetime/issue-107998.rs new file mode 100644 index 00000000000..f32688d2058 --- /dev/null +++ b/tests/ui/single-use-lifetime/issue-107998.rs @@ -0,0 +1,9 @@ +#![deny(single_use_lifetimes)] + +fn with(f: &fn<'a>(x: &'a i32) -> R) -> R { + //~^ ERROR function pointer types may not have generic parameters + //~| ERROR lifetime parameter `'a` only used once + f(&3) +} + +fn main() {} diff --git a/tests/ui/single-use-lifetime/issue-107998.stderr b/tests/ui/single-use-lifetime/issue-107998.stderr new file mode 100644 index 00000000000..e870351de9e --- /dev/null +++ b/tests/ui/single-use-lifetime/issue-107998.stderr @@ -0,0 +1,30 @@ +error: function pointer types may not have generic parameters + --> $DIR/issue-107998.rs:3:18 + | +LL | fn with(f: &fn<'a>(x: &'a i32) -> R) -> R { + | ^^^^ + | +help: consider moving the lifetime parameter to a `for` parameter list + | +LL - fn with(f: &fn<'a>(x: &'a i32) -> R) -> R { +LL + fn with(f: &for<'a> fn(x: &'a i32) -> R) -> R { + | + +error: lifetime parameter `'a` only used once + --> $DIR/issue-107998.rs:3:19 + | +LL | fn with(f: &fn<'a>(x: &'a i32) -> R) -> R { + | ^^ --- + | | | + | | ...is used only here + | | help: elide the single-use lifetime + | this lifetime... + | +note: the lint level is defined here + --> $DIR/issue-107998.rs:1:9 + | +LL | #![deny(single_use_lifetimes)] + | ^^^^^^^^^^^^^^^^^^^^ + +error: aborting due to 2 previous errors +