bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Enhance well-formedness checks for #[repr(...)] attributes

Browse source
This commit is contained in:
Fabian Wolff 2021-07-09 22:03:48 +02:00
parent e916b7cb77
commit a7bfd35966
8 changed files with 234 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

104
compiler/rustc_attr/src/builtin.rs
View file

@ -870,6 +870,23 @@ pub fn find_repr_attrs(sess: &Session, attr: &Attribute) -> Vec<ReprAttr> {
sym::simd => Some(ReprSimd),
sym::transparent => Some(ReprTransparent),
sym::no_niche => Some(ReprNoNiche),
sym::align => {
let mut err = struct_span_err!(
diagnostic,
item.span(),
E0589,
"invalid `repr(align)` attribute: `align` needs an argument"
);
err.span_suggestion(
item.span(),
"supply an argument here",
"align(...)".to_string(),
Applicability::HasPlaceholders,
);
err.emit();
recognised = true;
None
}
name => int_type_of_word(name).map(ReprInt),
};
@ -891,33 +908,47 @@ pub fn find_repr_attrs(sess: &Session, attr: &Attribute) -> Vec<ReprAttr> {
Ok(literal) => acc.push(ReprPacked(literal)),
Err(message) => literal_error = Some(message),
};
} else if matches!(name, sym::C | sym::simd | sym::transparent | sym::no_niche)
|| int_type_of_word(name).is_some()
{
recognised = true;
struct_span_err!(
diagnostic,
item.span(),
E0552,
"invalid representation hint: `{}` does not take a parenthesized argument list",
name.to_ident_string(),
).emit();
}
if let Some(literal_error) = literal_error {
struct_span_err!(
diagnostic,
item.span(),
E0589,
"invalid `repr(align)` attribute: {}",
"invalid `repr({})` attribute: {}",
name.to_ident_string(),
literal_error
)
.emit();
}
} else if let Some(meta_item) = item.meta_item() {
if meta_item.has_name(sym::align) {
if let MetaItemKind::NameValue(ref value) = meta_item.kind {
if let MetaItemKind::NameValue(ref value) = meta_item.kind {
if meta_item.has_name(sym::align) || meta_item.has_name(sym::packed) {
let name = meta_item.name_or_empty().to_ident_string();
recognised = true;
let mut err = struct_span_err!(
diagnostic,
item.span(),
E0693,
"incorrect `repr(align)` attribute format"
"incorrect `repr({})` attribute format",
name,
);
match value.kind {
ast::LitKind::Int(int, ast::LitIntType::Unsuffixed) => {
err.span_suggestion(
item.span(),
"use parentheses instead",
format!("align({})", int),
format!("{}({})", name, int),
Applicability::MachineApplicable,
);
}
@ -925,19 +956,76 @@ pub fn find_repr_attrs(sess: &Session, attr: &Attribute) -> Vec<ReprAttr> {
err.span_suggestion(
item.span(),
"use parentheses instead",
format!("align({})", s),
format!("{}({})", name, s),
Applicability::MachineApplicable,
);
}
_ => {}
}
err.emit();
} else {
if matches!(
meta_item.name_or_empty(),
sym::C | sym::simd | sym::transparent | sym::no_niche
) || int_type_of_word(meta_item.name_or_empty()).is_some()
{
recognised = true;
struct_span_err!(
diagnostic,
meta_item.span,
E0552,
"invalid representation hint: `{}` does not take a value",
meta_item.name_or_empty().to_ident_string(),
)
.emit();
}
}
} else if let MetaItemKind::List(_) = meta_item.kind {
if meta_item.has_name(sym::align) {
recognised = true;
struct_span_err!(
diagnostic,
meta_item.span,
E0693,
"incorrect `repr(align)` attribute format: \
`align` takes exactly one argument in parentheses"
)
.emit();
} else if meta_item.has_name(sym::packed) {
recognised = true;
struct_span_err!(
diagnostic,
meta_item.span,
E0552,
"incorrect `repr(packed)` attribute format: \
`packed` takes exactly one parenthesized argument, \
or no parentheses at all"
)
.emit();
} else if matches!(
meta_item.name_or_empty(),
sym::C | sym::simd | sym::transparent | sym::no_niche
) || int_type_of_word(meta_item.name_or_empty()).is_some()
{
recognised = true;
struct_span_err!(
diagnostic,
meta_item.span,
E0552,
"invalid representation hint: `{}` does not take a parenthesized argument list",
meta_item.name_or_empty().to_ident_string(),
).emit();
}
}
}
if !recognised {
// Not a word we recognize
diagnostic.delay_span_bug(item.span(), "unrecognized representation hint");
// Not a word we recognize. This will be caught and reported by
// the `check_mod_attrs` pass, but this pass doesn't always run
// (e.g. if we only pretty-print the source), so we have to gate
// the `delay_span_bug` call as follows:
if sess.opts.pretty.map_or(true, |pp| pp.needs_analysis()) {
diagnostic.delay_span_bug(item.span(), "unrecognized representation hint");
}
}
}
}