mirror of
https://github.com/rust-lang/rust-clippy
synced 2024-11-10 15:14:29 +00:00
Use approx_ty_size
for large_enum_variant
This commit is contained in:
parent
30e4532153
commit
584000a792
6 changed files with 269 additions and 141 deletions
|
@ -1,13 +1,12 @@
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//! lint when there is a large size difference between variants on an enum
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use clippy_utils::source::snippet_with_applicability;
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use clippy_utils::{diagnostics::span_lint_and_then, ty::is_copy};
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use clippy_utils::{diagnostics::span_lint_and_then, ty::approx_ty_size, ty::is_copy};
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use rustc_errors::Applicability;
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use rustc_hir::{Item, ItemKind};
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use rustc_lint::{LateContext, LateLintPass};
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use rustc_middle::lint::in_external_macro;
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use rustc_middle::ty::layout::LayoutOf;
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use rustc_middle::ty::{Adt, Ty};
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use rustc_middle::ty::{Adt, AdtDef, GenericArg, List, Ty};
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use rustc_session::{declare_tool_lint, impl_lint_pass};
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use rustc_span::source_map::Span;
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@ -17,7 +16,7 @@ declare_clippy_lint! {
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/// `enum`s.
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///
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/// ### Why is this bad?
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/// Enum size is bounded by the largest variant. Having a
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/// Enum size is bounded by the largest variant. Having one
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/// large variant can penalize the memory layout of that enum.
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///
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/// ### Known problems
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@ -33,8 +32,9 @@ declare_clippy_lint! {
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/// use case it may be possible to store the large data in an auxiliary
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/// structure (e.g. Arena or ECS).
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///
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/// The lint will ignore generic types if the layout depends on the
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/// generics, even if the size difference will be large anyway.
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/// The lint will ignore the impact of generic types to the type layout by
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/// assuming every type parameter is zero-sized. Depending on your use case,
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/// this may lead to a false positive.
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///
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/// ### Example
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/// ```rust
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@ -83,6 +83,38 @@ struct VariantInfo {
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fields_size: Vec<FieldInfo>,
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}
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fn variants_size<'tcx>(
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cx: &LateContext<'tcx>,
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adt: AdtDef<'tcx>,
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subst: &'tcx List<GenericArg<'tcx>>,
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) -> Vec<VariantInfo> {
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let mut variants_size = adt
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.variants()
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.iter()
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.enumerate()
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.map(|(i, variant)| {
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let mut fields_size = variant
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.fields
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.iter()
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.enumerate()
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.map(|(i, f)| FieldInfo {
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ind: i,
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size: approx_ty_size(cx, f.ty(cx.tcx, subst)),
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})
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.collect::<Vec<_>>();
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fields_size.sort_by(|a, b| (a.size.cmp(&b.size)));
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VariantInfo {
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ind: i,
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size: fields_size.iter().map(|info| info.size).sum(),
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fields_size,
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}
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})
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.collect::<Vec<_>>();
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variants_size.sort_by(|a, b| (b.size.cmp(&a.size)));
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variants_size
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}
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impl_lint_pass!(LargeEnumVariant => [LARGE_ENUM_VARIANT]);
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impl<'tcx> LateLintPass<'tcx> for LargeEnumVariant {
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@ -92,36 +124,14 @@ impl<'tcx> LateLintPass<'tcx> for LargeEnumVariant {
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}
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if let ItemKind::Enum(ref def, _) = item.kind {
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let ty = cx.tcx.type_of(item.def_id);
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let adt = ty.ty_adt_def().expect("already checked whether this is an enum");
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let (adt, subst) = match ty.kind() {
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Adt(adt, subst) => (adt, subst),
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_ => panic!("already checked whether this is an enum"),
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};
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if adt.variants().len() <= 1 {
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return;
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}
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let mut variants_size: Vec<VariantInfo> = Vec::new();
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for (i, variant) in adt.variants().iter().enumerate() {
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let mut fields_size = Vec::new();
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for (i, f) in variant.fields.iter().enumerate() {
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let ty = cx.tcx.type_of(f.did);
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// don't lint variants which have a field of generic type.
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match cx.layout_of(ty) {
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Ok(l) => {
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let fsize = l.size.bytes();
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fields_size.push(FieldInfo { ind: i, size: fsize });
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},
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Err(_) => {
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return;
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},
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}
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}
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let size: u64 = fields_size.iter().map(|info| info.size).sum();
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variants_size.push(VariantInfo {
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ind: i,
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size,
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fields_size,
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});
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}
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variants_size.sort_by(|a, b| (b.size.cmp(&a.size)));
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let variants_size = variants_size(cx, *adt, subst);
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let mut difference = variants_size[0].size - variants_size[1].size;
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if difference > self.maximum_size_difference_allowed {
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@ -129,20 +139,30 @@ impl<'tcx> LateLintPass<'tcx> for LargeEnumVariant {
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span_lint_and_then(
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cx,
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LARGE_ENUM_VARIANT,
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def.variants[variants_size[0].ind].span,
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item.span,
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"large size difference between variants",
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|diag| {
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diag.span_label(
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def.variants[variants_size[0].ind].span,
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&format!("this variant is {} bytes", variants_size[0].size),
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item.span,
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format!("the entire enum is at least {} bytes", approx_ty_size(cx, ty)),
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);
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diag.span_note(
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diag.span_label(
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def.variants[variants_size[0].ind].span,
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format!("the largest variant contains at least {} bytes", variants_size[0].size),
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);
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diag.span_label(
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def.variants[variants_size[1].ind].span,
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&format!("and the second-largest variant is {} bytes:", variants_size[1].size),
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&if variants_size[1].fields_size.is_empty() {
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"the second-largest variant carries no data at all".to_owned()
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} else {
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format!(
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"the second-largest variant contains at least {} bytes",
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variants_size[1].size
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)
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},
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);
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let fields = def.variants[variants_size[0].ind].data.fields();
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variants_size[0].fields_size.sort_by(|a, b| (a.size.cmp(&b.size)));
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let mut applicability = Applicability::MaybeIncorrect;
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if is_copy(cx, ty) || maybe_copy(cx, ty) {
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diag.span_note(
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@ -3,7 +3,7 @@ Checks for large size differences between variants on
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`enum`s.
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### Why is this bad?
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Enum size is bounded by the largest variant. Having a
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Enum size is bounded by the largest variant. Having one
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large variant can penalize the memory layout of that enum.
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### Known problems
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@ -19,8 +19,9 @@ still be `Clone`, but that is worse ergonomically. Depending on the
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use case it may be possible to store the large data in an auxiliary
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structure (e.g. Arena or ECS).
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The lint will ignore generic types if the layout depends on the
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generics, even if the size difference will be large anyway.
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The lint will ignore the impact of generic types to the type layout by
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assuming every type parameter is zero-sized. Depending on your use case,
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this may lead to a false positive.
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### Example
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```
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@ -130,6 +130,30 @@ impl<T: Copy> Clone for SomeGenericPossiblyCopyEnum<T> {
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impl<T: Copy> Copy for SomeGenericPossiblyCopyEnum<T> {}
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enum LargeEnumWithGenerics<T> {
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Small,
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Large((T, [u8; 512])),
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}
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struct Foo<T> {
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foo: T,
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}
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enum WithGenerics {
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Large([Foo<u64>; 64]),
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Small(u8),
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}
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enum PossiblyLargeEnumWithConst<const U: usize> {
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SmallBuffer([u8; 4]),
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MightyBuffer([u16; U]),
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}
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enum LargeEnumOfConst {
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Ok,
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Error(PossiblyLargeEnumWithConst<256>),
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}
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fn main() {
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large_enum_variant!();
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}
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@ -1,143 +1,177 @@
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error: large size difference between variants
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--> $DIR/large_enum_variant.rs:12:5
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--> $DIR/large_enum_variant.rs:10:1
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LL | B([i32; 8000]),
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| ^^^^^^^^^^^^^^ this variant is 32000 bytes
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LL | / enum LargeEnum {
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LL | | A(i32),
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| | ------ the second-largest variant contains at least 4 bytes
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LL | | B([i32; 8000]),
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| | -------------- the largest variant contains at least 32000 bytes
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LL | | }
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| |_^ the entire enum is at least 32004 bytes
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= note: `-D clippy::large-enum-variant` implied by `-D warnings`
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note: and the second-largest variant is 4 bytes:
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--> $DIR/large_enum_variant.rs:11:5
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|
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LL | A(i32),
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| ^^^^^^
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help: consider boxing the large fields to reduce the total size of the enum
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|
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LL | B(Box<[i32; 8000]>),
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| ~~~~~~~~~~~~~~~~
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error: large size difference between variants
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--> $DIR/large_enum_variant.rs:36:5
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--> $DIR/large_enum_variant.rs:34:1
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|
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LL | ContainingLargeEnum(LargeEnum),
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| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this variant is 32004 bytes
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LL | / enum LargeEnum2 {
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LL | | VariantOk(i32, u32),
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| | ------------------- the second-largest variant contains at least 8 bytes
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LL | | ContainingLargeEnum(LargeEnum),
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| | ------------------------------ the largest variant contains at least 32004 bytes
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LL | | }
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| |_^ the entire enum is at least 32008 bytes
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|
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note: and the second-largest variant is 8 bytes:
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--> $DIR/large_enum_variant.rs:35:5
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|
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LL | VariantOk(i32, u32),
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| ^^^^^^^^^^^^^^^^^^^
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help: consider boxing the large fields to reduce the total size of the enum
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|
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LL | ContainingLargeEnum(Box<LargeEnum>),
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| ~~~~~~~~~~~~~~
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error: large size difference between variants
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--> $DIR/large_enum_variant.rs:40:5
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--> $DIR/large_enum_variant.rs:39:1
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|
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LL | ContainingMoreThanOneField(i32, [i32; 8000], [i32; 9500]),
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| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this variant is 70004 bytes
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LL | / enum LargeEnum3 {
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LL | | ContainingMoreThanOneField(i32, [i32; 8000], [i32; 9500]),
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| | --------------------------------------------------------- the largest variant contains at least 70004 bytes
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LL | | VoidVariant,
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LL | | StructLikeLittle { x: i32, y: i32 },
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| | ----------------------------------- the second-largest variant contains at least 8 bytes
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LL | | }
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| |_^ the entire enum is at least 70008 bytes
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|
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note: and the second-largest variant is 8 bytes:
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--> $DIR/large_enum_variant.rs:42:5
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|
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LL | StructLikeLittle { x: i32, y: i32 },
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| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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help: consider boxing the large fields to reduce the total size of the enum
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|
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LL | ContainingMoreThanOneField(i32, Box<[i32; 8000]>, Box<[i32; 9500]>),
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| ~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~
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error: large size difference between variants
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--> $DIR/large_enum_variant.rs:47:5
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--> $DIR/large_enum_variant.rs:45:1
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|
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LL | StructLikeLarge { x: [i32; 8000], y: i32 },
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| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this variant is 32004 bytes
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LL | / enum LargeEnum4 {
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LL | | VariantOk(i32, u32),
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| | ------------------- the second-largest variant contains at least 8 bytes
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LL | | StructLikeLarge { x: [i32; 8000], y: i32 },
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| | ------------------------------------------ the largest variant contains at least 32004 bytes
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LL | | }
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| |_^ the entire enum is at least 32008 bytes
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|
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note: and the second-largest variant is 8 bytes:
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--> $DIR/large_enum_variant.rs:46:5
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|
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LL | VariantOk(i32, u32),
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| ^^^^^^^^^^^^^^^^^^^
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help: consider boxing the large fields to reduce the total size of the enum
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|
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LL | StructLikeLarge { x: Box<[i32; 8000]>, y: i32 },
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| ~~~~~~~~~~~~~~~~
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error: large size difference between variants
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--> $DIR/large_enum_variant.rs:52:5
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--> $DIR/large_enum_variant.rs:50:1
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|
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LL | StructLikeLarge2 { x: [i32; 8000] },
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| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this variant is 32000 bytes
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LL | / enum LargeEnum5 {
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LL | | VariantOk(i32, u32),
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| | ------------------- the second-largest variant contains at least 8 bytes
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LL | | StructLikeLarge2 { x: [i32; 8000] },
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| | ----------------------------------- the largest variant contains at least 32000 bytes
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LL | | }
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| |_^ the entire enum is at least 32004 bytes
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|
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note: and the second-largest variant is 8 bytes:
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--> $DIR/large_enum_variant.rs:51:5
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|
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LL | VariantOk(i32, u32),
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| ^^^^^^^^^^^^^^^^^^^
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help: consider boxing the large fields to reduce the total size of the enum
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|
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LL | StructLikeLarge2 { x: Box<[i32; 8000]> },
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| ~~~~~~~~~~~~~~~~
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error: large size difference between variants
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--> $DIR/large_enum_variant.rs:68:5
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--> $DIR/large_enum_variant.rs:66:1
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|
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LL | B([u8; 1255]),
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| ^^^^^^^^^^^^^ this variant is 1255 bytes
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LL | / enum LargeEnum7 {
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LL | | A,
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LL | | B([u8; 1255]),
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| | ------------- the largest variant contains at least 1255 bytes
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LL | | C([u8; 200]),
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| | ------------ the second-largest variant contains at least 200 bytes
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LL | | }
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| |_^ the entire enum is at least 1256 bytes
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|
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note: and the second-largest variant is 200 bytes:
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--> $DIR/large_enum_variant.rs:69:5
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|
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LL | C([u8; 200]),
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| ^^^^^^^^^^^^
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help: consider boxing the large fields to reduce the total size of the enum
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|
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LL | B(Box<[u8; 1255]>),
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| ~~~~~~~~~~~~~~~
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error: large size difference between variants
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--> $DIR/large_enum_variant.rs:74:5
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--> $DIR/large_enum_variant.rs:72:1
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|
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LL | ContainingMoreThanOneField([i32; 8000], [i32; 2], [i32; 9500], [i32; 30]),
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| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this variant is 70128 bytes
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LL | / enum LargeEnum8 {
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LL | | VariantOk(i32, u32),
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| | ------------------- the second-largest variant contains at least 8 bytes
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LL | | ContainingMoreThanOneField([i32; 8000], [i32; 2], [i32; 9500], [i32; 30]),
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| | ------------------------------------------------------------------------- the largest variant contains at least 70128 bytes
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LL | | }
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| |_^ the entire enum is at least 70132 bytes
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|
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note: and the second-largest variant is 8 bytes:
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--> $DIR/large_enum_variant.rs:73:5
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|
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LL | VariantOk(i32, u32),
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| ^^^^^^^^^^^^^^^^^^^
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help: consider boxing the large fields to reduce the total size of the enum
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|
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LL | ContainingMoreThanOneField(Box<[i32; 8000]>, [i32; 2], Box<[i32; 9500]>, [i32; 30]),
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| ~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~
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error: large size difference between variants
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--> $DIR/large_enum_variant.rs:79:5
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--> $DIR/large_enum_variant.rs:77:1
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|
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LL | B(Struct2),
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| ^^^^^^^^^^ this variant is 32000 bytes
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LL | / enum LargeEnum9 {
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LL | | A(Struct<()>),
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| | ------------- the second-largest variant contains at least 4 bytes
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LL | | B(Struct2),
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| | ---------- the largest variant contains at least 32000 bytes
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LL | | }
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| |_^ the entire enum is at least 32004 bytes
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|
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note: and the second-largest variant is 4 bytes:
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--> $DIR/large_enum_variant.rs:78:5
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|
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LL | A(Struct<()>),
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| ^^^^^^^^^^^^^
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help: consider boxing the large fields to reduce the total size of the enum
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|
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LL | B(Box<Struct2>),
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| ~~~~~~~~~~~~
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error: large size difference between variants
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--> $DIR/large_enum_variant.rs:104:5
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--> $DIR/large_enum_variant.rs:82:1
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|
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LL | B([u128; 4000]),
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| ^^^^^^^^^^^^^^^ this variant is 64000 bytes
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LL | / enum LargeEnumOk2<T> {
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LL | | A(T),
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| | ---- the second-largest variant contains at least 0 bytes
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LL | | B(Struct2),
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| | ---------- the largest variant contains at least 32000 bytes
|
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LL | | }
|
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| |_^ the entire enum is at least 32000 bytes
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|
|
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note: and the second-largest variant is 1 bytes:
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--> $DIR/large_enum_variant.rs:103:5
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help: consider boxing the large fields to reduce the total size of the enum
|
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|
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LL | B(Box<Struct2>),
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| ~~~~~~~~~~~~
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error: large size difference between variants
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--> $DIR/large_enum_variant.rs:87:1
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|
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LL | / enum LargeEnumOk3<T> {
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LL | | A(Struct<T>),
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| | ------------ the second-largest variant contains at least 4 bytes
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LL | | B(Struct2),
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| | ---------- the largest variant contains at least 32000 bytes
|
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LL | | }
|
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| |_^ the entire enum is at least 32000 bytes
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|
|
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help: consider boxing the large fields to reduce the total size of the enum
|
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|
|
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LL | B(Box<Struct2>),
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| ~~~~~~~~~~~~
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||||
|
||||
error: large size difference between variants
|
||||
--> $DIR/large_enum_variant.rs:102:1
|
||||
|
|
||||
LL | / enum CopyableLargeEnum {
|
||||
LL | | A(bool),
|
||||
| | ------- the second-largest variant contains at least 1 bytes
|
||||
LL | | B([u128; 4000]),
|
||||
| | --------------- the largest variant contains at least 64000 bytes
|
||||
LL | | }
|
||||
| |_^ the entire enum is at least 64008 bytes
|
||||
|
|
||||
LL | A(bool),
|
||||
| ^^^^^^^
|
||||
note: boxing a variant would require the type no longer be `Copy`
|
||||
--> $DIR/large_enum_variant.rs:102:6
|
||||
|
|
||||
|
@ -150,16 +184,16 @@ LL | B([u128; 4000]),
|
|||
| ^^^^^^^^^^^^^^^
|
||||
|
||||
error: large size difference between variants
|
||||
--> $DIR/large_enum_variant.rs:109:5
|
||||
--> $DIR/large_enum_variant.rs:107:1
|
||||
|
|
||||
LL | B([u128; 4000]),
|
||||
| ^^^^^^^^^^^^^^^ this variant is 64000 bytes
|
||||
LL | / enum ManuallyCopyLargeEnum {
|
||||
LL | | A(bool),
|
||||
| | ------- the second-largest variant contains at least 1 bytes
|
||||
LL | | B([u128; 4000]),
|
||||
| | --------------- the largest variant contains at least 64000 bytes
|
||||
LL | | }
|
||||
| |_^ the entire enum is at least 64008 bytes
|
||||
|
|
||||
note: and the second-largest variant is 1 bytes:
|
||||
--> $DIR/large_enum_variant.rs:108:5
|
||||
|
|
||||
LL | A(bool),
|
||||
| ^^^^^^^
|
||||
note: boxing a variant would require the type no longer be `Copy`
|
||||
--> $DIR/large_enum_variant.rs:107:6
|
||||
|
|
||||
|
@ -172,16 +206,16 @@ LL | B([u128; 4000]),
|
|||
| ^^^^^^^^^^^^^^^
|
||||
|
||||
error: large size difference between variants
|
||||
--> $DIR/large_enum_variant.rs:122:5
|
||||
--> $DIR/large_enum_variant.rs:120:1
|
||||
|
|
||||
LL | B([u64; 4000]),
|
||||
| ^^^^^^^^^^^^^^ this variant is 32000 bytes
|
||||
LL | / enum SomeGenericPossiblyCopyEnum<T> {
|
||||
LL | | A(bool, std::marker::PhantomData<T>),
|
||||
| | ------------------------------------ the second-largest variant contains at least 1 bytes
|
||||
LL | | B([u64; 4000]),
|
||||
| | -------------- the largest variant contains at least 32000 bytes
|
||||
LL | | }
|
||||
| |_^ the entire enum is at least 32008 bytes
|
||||
|
|
||||
note: and the second-largest variant is 1 bytes:
|
||||
--> $DIR/large_enum_variant.rs:121:5
|
||||
|
|
||||
LL | A(bool, std::marker::PhantomData<T>),
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
note: boxing a variant would require the type no longer be `Copy`
|
||||
--> $DIR/large_enum_variant.rs:120:6
|
||||
|
|
||||
|
@ -193,5 +227,53 @@ help: consider boxing the large fields to reduce the total size of the enum
|
|||
LL | B([u64; 4000]),
|
||||
| ^^^^^^^^^^^^^^
|
||||
|
||||
error: aborting due to 11 previous errors
|
||||
error: large size difference between variants
|
||||
--> $DIR/large_enum_variant.rs:133:1
|
||||
|
|
||||
LL | / enum LargeEnumWithGenerics<T> {
|
||||
LL | | Small,
|
||||
| | ----- the second-largest variant carries no data at all
|
||||
LL | | Large((T, [u8; 512])),
|
||||
| | --------------------- the largest variant contains at least 512 bytes
|
||||
LL | | }
|
||||
| |_^ the entire enum is at least 512 bytes
|
||||
|
|
||||
help: consider boxing the large fields to reduce the total size of the enum
|
||||
|
|
||||
LL | Large(Box<(T, [u8; 512])>),
|
||||
| ~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
error: large size difference between variants
|
||||
--> $DIR/large_enum_variant.rs:142:1
|
||||
|
|
||||
LL | / enum WithGenerics {
|
||||
LL | | Large([Foo<u64>; 64]),
|
||||
| | --------------------- the largest variant contains at least 512 bytes
|
||||
LL | | Small(u8),
|
||||
| | --------- the second-largest variant contains at least 1 bytes
|
||||
LL | | }
|
||||
| |_^ the entire enum is at least 520 bytes
|
||||
|
|
||||
help: consider boxing the large fields to reduce the total size of the enum
|
||||
|
|
||||
LL | Large(Box<[Foo<u64>; 64]>),
|
||||
| ~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
error: large size difference between variants
|
||||
--> $DIR/large_enum_variant.rs:152:1
|
||||
|
|
||||
LL | / enum LargeEnumOfConst {
|
||||
LL | | Ok,
|
||||
| | -- the second-largest variant carries no data at all
|
||||
LL | | Error(PossiblyLargeEnumWithConst<256>),
|
||||
| | -------------------------------------- the largest variant contains at least 514 bytes
|
||||
LL | | }
|
||||
| |_^ the entire enum is at least 514 bytes
|
||||
|
|
||||
help: consider boxing the large fields to reduce the total size of the enum
|
||||
|
|
||||
LL | Error(Box<PossiblyLargeEnumWithConst<256>>),
|
||||
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
error: aborting due to 16 previous errors
|
||||
|
||||
|
|
|
@ -1,4 +1,5 @@
|
|||
#![warn(clippy::result_large_err)]
|
||||
#![allow(clippy::large_enum_variant)]
|
||||
|
||||
pub fn small_err() -> Result<(), u128> {
|
||||
Ok(())
|
||||
|
|
|
@ -1,5 +1,5 @@
|
|||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:7:23
|
||||
--> $DIR/result_large_err.rs:8:23
|
||||
|
|
||||
LL | pub fn large_err() -> Result<(), [u8; 512]> {
|
||||
| ^^^^^^^^^^^^^^^^^^^^^ the `Err`-variant is at least 512 bytes
|
||||
|
@ -8,7 +8,7 @@ LL | pub fn large_err() -> Result<(), [u8; 512]> {
|
|||
= help: try reducing the size of `[u8; 512]`, for example by boxing large elements or replacing it with `Box<[u8; 512]>`
|
||||
|
||||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:18:21
|
||||
--> $DIR/result_large_err.rs:19:21
|
||||
|
|
||||
LL | pub fn ret() -> Result<(), Self> {
|
||||
| ^^^^^^^^^^^^^^^^ the `Err`-variant is at least 240 bytes
|
||||
|
@ -16,7 +16,7 @@ LL | pub fn ret() -> Result<(), Self> {
|
|||
= help: try reducing the size of `FullyDefinedLargeError`, for example by boxing large elements or replacing it with `Box<FullyDefinedLargeError>`
|
||||
|
||||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:23:26
|
||||
--> $DIR/result_large_err.rs:24:26
|
||||
|
|
||||
LL | pub fn struct_error() -> Result<(), FullyDefinedLargeError> {
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the `Err`-variant is at least 240 bytes
|
||||
|
@ -24,7 +24,7 @@ LL | pub fn struct_error() -> Result<(), FullyDefinedLargeError> {
|
|||
= help: try reducing the size of `FullyDefinedLargeError`, for example by boxing large elements or replacing it with `Box<FullyDefinedLargeError>`
|
||||
|
||||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:28:45
|
||||
--> $DIR/result_large_err.rs:29:45
|
||||
|
|
||||
LL | pub fn large_err_via_type_alias<T>(x: T) -> Fdlr<T> {
|
||||
| ^^^^^^^ the `Err`-variant is at least 240 bytes
|
||||
|
@ -32,7 +32,7 @@ LL | pub fn large_err_via_type_alias<T>(x: T) -> Fdlr<T> {
|
|||
= help: try reducing the size of `FullyDefinedLargeError`, for example by boxing large elements or replacing it with `Box<FullyDefinedLargeError>`
|
||||
|
||||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:36:34
|
||||
--> $DIR/result_large_err.rs:37:34
|
||||
|
|
||||
LL | pub fn param_large_error<R>() -> Result<(), (u128, R, FullyDefinedLargeError)> {
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the `Err`-variant is at least 256 bytes
|
||||
|
@ -40,7 +40,7 @@ LL | pub fn param_large_error<R>() -> Result<(), (u128, R, FullyDefinedLargeErro
|
|||
= help: try reducing the size of `(u128, R, FullyDefinedLargeError)`, for example by boxing large elements or replacing it with `Box<(u128, R, FullyDefinedLargeError)>`
|
||||
|
||||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:47:34
|
||||
--> $DIR/result_large_err.rs:48:34
|
||||
|
|
||||
LL | pub fn large_enum_error() -> Result<(), Self> {
|
||||
| ^^^^^^^^^^^^^^^^ the `Err`-variant is at least 513 bytes
|
||||
|
@ -48,7 +48,7 @@ LL | pub fn large_enum_error() -> Result<(), Self> {
|
|||
= help: try reducing the size of `LargeErrorVariants<()>`, for example by boxing large elements or replacing it with `Box<LargeErrorVariants<()>>`
|
||||
|
||||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:53:25
|
||||
--> $DIR/result_large_err.rs:54:25
|
||||
|
|
||||
LL | fn large_error() -> Result<(), [u8; 512]> {
|
||||
| ^^^^^^^^^^^^^^^^^^^^^ the `Err`-variant is at least 512 bytes
|
||||
|
@ -56,7 +56,7 @@ LL | fn large_error() -> Result<(), [u8; 512]> {
|
|||
= help: try reducing the size of `[u8; 512]`, for example by boxing large elements or replacing it with `Box<[u8; 512]>`
|
||||
|
||||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:72:29
|
||||
--> $DIR/result_large_err.rs:73:29
|
||||
|
|
||||
LL | pub fn large_union_err() -> Result<(), FullyDefinedUnionError> {
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the `Err`-variant is at least 512 bytes
|
||||
|
@ -64,7 +64,7 @@ LL | pub fn large_union_err() -> Result<(), FullyDefinedUnionError> {
|
|||
= help: try reducing the size of `FullyDefinedUnionError`, for example by boxing large elements or replacing it with `Box<FullyDefinedUnionError>`
|
||||
|
||||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:81:40
|
||||
--> $DIR/result_large_err.rs:82:40
|
||||
|
|
||||
LL | pub fn param_large_union<T: Copy>() -> Result<(), UnionError<T>> {
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^ the `Err`-variant is at least 512 bytes
|
||||
|
@ -72,7 +72,7 @@ LL | pub fn param_large_union<T: Copy>() -> Result<(), UnionError<T>> {
|
|||
= help: try reducing the size of `UnionError<T>`, for example by boxing large elements or replacing it with `Box<UnionError<T>>`
|
||||
|
||||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:90:34
|
||||
--> $DIR/result_large_err.rs:91:34
|
||||
|
|
||||
LL | pub fn array_error_subst<U>() -> Result<(), ArrayError<i32, U>> {
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the `Err`-variant is at least 128 bytes
|
||||
|
@ -80,7 +80,7 @@ LL | pub fn array_error_subst<U>() -> Result<(), ArrayError<i32, U>> {
|
|||
= help: try reducing the size of `ArrayError<i32, U>`, for example by boxing large elements or replacing it with `Box<ArrayError<i32, U>>`
|
||||
|
||||
error: the `Err`-variant returned from this function is very large
|
||||
--> $DIR/result_large_err.rs:94:31
|
||||
--> $DIR/result_large_err.rs:95:31
|
||||
|
|
||||
LL | pub fn array_error<T, U>() -> Result<(), ArrayError<(i32, T), U>> {
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the `Err`-variant is at least 128 bytes
|
||||
|
|
Loading…
Reference in a new issue