Determine function unsafety semantically

This commit is contained in:
Jonas Schievink 2022-04-07 18:33:03 +02:00
parent 12f803d1e3
commit 5d8b4c40eb
12 changed files with 107 additions and 98 deletions

View file

@ -26,16 +26,16 @@ impl HirDisplay for Function {
fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> {
let data = f.db.function_data(self.id);
write_visibility(self.module(f.db).id, self.visibility(f.db), f)?;
if data.is_default() {
if data.has_default_kw() {
f.write_str("default ")?;
}
if data.is_const() {
if data.has_const_kw() {
f.write_str("const ")?;
}
if data.is_async() {
if data.has_async_kw() {
f.write_str("async ")?;
}
if data.is_unsafe() {
if self.is_unsafe_to_call(f.db) {
f.write_str("unsafe ")?;
}
if let Some(abi) = &data.abi {
@ -96,7 +96,7 @@ impl HirDisplay for Function {
// `FunctionData::ret_type` will be `::core::future::Future<Output = ...>` for async fns.
// Use ugly pattern match to strip the Future trait.
// Better way?
let ret_type = if !data.is_async() {
let ret_type = if !data.has_async_kw() {
&data.ret_type
} else {
match &*data.ret_type {

View file

@ -1421,16 +1421,16 @@ impl Function {
.collect()
}
pub fn is_unsafe(self, db: &dyn HirDatabase) -> bool {
db.function_data(self.id).is_unsafe()
}
pub fn is_const(self, db: &dyn HirDatabase) -> bool {
db.function_data(self.id).is_const()
db.function_data(self.id).has_const_kw()
}
pub fn is_async(self, db: &dyn HirDatabase) -> bool {
db.function_data(self.id).is_async()
db.function_data(self.id).has_async_kw()
}
pub fn is_unsafe_to_call(self, db: &dyn HirDatabase) -> bool {
hir_ty::is_fn_unsafe_to_call(db, self.id)
}
/// Whether this function declaration has a definition.

View file

@ -110,20 +110,20 @@ impl FunctionData {
self.flags.contains(FnFlags::HAS_SELF_PARAM)
}
pub fn is_default(&self) -> bool {
self.flags.contains(FnFlags::IS_DEFAULT)
pub fn has_default_kw(&self) -> bool {
self.flags.contains(FnFlags::HAS_DEFAULT_KW)
}
pub fn is_const(&self) -> bool {
self.flags.contains(FnFlags::IS_CONST)
pub fn has_const_kw(&self) -> bool {
self.flags.contains(FnFlags::HAS_CONST_KW)
}
pub fn is_async(&self) -> bool {
self.flags.contains(FnFlags::IS_ASYNC)
pub fn has_async_kw(&self) -> bool {
self.flags.contains(FnFlags::HAS_ASYNC_KW)
}
pub fn is_unsafe(&self) -> bool {
self.flags.contains(FnFlags::IS_UNSAFE)
pub fn has_unsafe_kw(&self) -> bool {
self.flags.contains(FnFlags::HAS_UNSAFE_KW)
}
pub fn is_varargs(&self) -> bool {

View file

@ -606,10 +606,10 @@ bitflags::bitflags! {
pub(crate) struct FnFlags: u8 {
const HAS_SELF_PARAM = 1 << 0;
const HAS_BODY = 1 << 1;
const IS_DEFAULT = 1 << 2;
const IS_CONST = 1 << 3;
const IS_ASYNC = 1 << 4;
const IS_UNSAFE = 1 << 5;
const HAS_DEFAULT_KW = 1 << 2;
const HAS_CONST_KW = 1 << 3;
const HAS_ASYNC_KW = 1 << 4;
const HAS_UNSAFE_KW = 1 << 5;
const IS_VARARGS = 1 << 6;
}
}

View file

@ -2,7 +2,7 @@
use std::{collections::hash_map::Entry, mem, sync::Arc};
use hir_expand::{ast_id_map::AstIdMap, hygiene::Hygiene, name::known, HirFileId};
use hir_expand::{ast_id_map::AstIdMap, hygiene::Hygiene, HirFileId};
use syntax::ast::{self, HasModuleItem};
use crate::{
@ -343,16 +343,16 @@ impl<'a> Ctx<'a> {
flags |= FnFlags::HAS_SELF_PARAM;
}
if func.default_token().is_some() {
flags |= FnFlags::IS_DEFAULT;
flags |= FnFlags::HAS_DEFAULT_KW;
}
if func.const_token().is_some() {
flags |= FnFlags::IS_CONST;
flags |= FnFlags::HAS_CONST_KW;
}
if func.async_token().is_some() {
flags |= FnFlags::IS_ASYNC;
flags |= FnFlags::HAS_ASYNC_KW;
}
if func.unsafe_token().is_some() {
flags |= FnFlags::IS_UNSAFE;
flags |= FnFlags::HAS_UNSAFE_KW;
}
let mut res = Function {
@ -554,22 +554,10 @@ impl<'a> Ctx<'a> {
// should be considered to be in an extern block too.
let attrs = RawAttrs::new(self.db, &item, self.hygiene());
let id: ModItem = match item {
ast::ExternItem::Fn(ast) => {
let func_id = self.lower_function(&ast)?;
let func = &mut self.data().functions[func_id.index];
if is_intrinsic_fn_unsafe(&func.name) {
// FIXME: this breaks in macros
func.flags |= FnFlags::IS_UNSAFE;
}
func_id.into()
}
ast::ExternItem::Fn(ast) => self.lower_function(&ast)?.into(),
ast::ExternItem::Static(ast) => self.lower_static(&ast)?.into(),
ast::ExternItem::TypeAlias(ty) => self.lower_type_alias(&ty)?.into(),
ast::ExternItem::MacroCall(call) => {
// FIXME: we need some way of tracking that the macro call is in an
// extern block
self.lower_macro_call(&call)?.into()
}
ast::ExternItem::MacroCall(call) => self.lower_macro_call(&call)?.into(),
};
self.add_attrs(id.into(), attrs);
Some(id)
@ -716,49 +704,6 @@ enum GenericsOwner<'a> {
Impl,
}
/// Returns `true` if the given intrinsic is unsafe to call, or false otherwise.
fn is_intrinsic_fn_unsafe(name: &Name) -> bool {
// Should be kept in sync with https://github.com/rust-lang/rust/blob/532d2b14c05f9bc20b2d27cbb5f4550d28343a36/compiler/rustc_typeck/src/check/intrinsic.rs#L72-L106
![
known::abort,
known::add_with_overflow,
known::bitreverse,
known::black_box,
known::bswap,
known::caller_location,
known::ctlz,
known::ctpop,
known::cttz,
known::discriminant_value,
known::forget,
known::likely,
known::maxnumf32,
known::maxnumf64,
known::min_align_of,
known::minnumf32,
known::minnumf64,
known::mul_with_overflow,
known::needs_drop,
known::ptr_guaranteed_eq,
known::ptr_guaranteed_ne,
known::rotate_left,
known::rotate_right,
known::rustc_peek,
known::saturating_add,
known::saturating_sub,
known::size_of,
known::sub_with_overflow,
known::type_id,
known::type_name,
known::unlikely,
known::variant_count,
known::wrapping_add,
known::wrapping_mul,
known::wrapping_sub,
]
.contains(name)
}
fn lower_abi(abi: ast::Abi) -> Interned<str> {
// FIXME: Abi::abi() -> Option<SyntaxToken>?
match abi.syntax().last_token() {

View file

@ -76,7 +76,6 @@ extern "C" {
pub(self) static EX_STATIC: u8 = _;
#[on_extern_fn] // AttrId { ast_index: 0 }
// flags = 0x20
pub(self) fn ex_fn() -> ();
}
"##]],

View file

@ -8,14 +8,16 @@ use hir_def::{
DefWithBodyId,
};
use crate::{db::HirDatabase, InferenceResult, Interner, TyExt, TyKind};
use crate::{
db::HirDatabase, utils::is_fn_unsafe_to_call, InferenceResult, Interner, TyExt, TyKind,
};
pub fn missing_unsafe(db: &dyn HirDatabase, def: DefWithBodyId) -> Vec<ExprId> {
let infer = db.infer(def);
let mut res = Vec::new();
let is_unsafe = match def {
DefWithBodyId::FunctionId(it) => db.function_data(it).is_unsafe(),
DefWithBodyId::FunctionId(it) => db.function_data(it).has_unsafe_kw(),
DefWithBodyId::StaticId(_) | DefWithBodyId::ConstId(_) => false,
};
if is_unsafe {
@ -62,7 +64,7 @@ fn walk_unsafe(
match expr {
&Expr::Call { callee, .. } => {
if let Some(func) = infer[callee].as_fn_def(db) {
if db.function_data(func).is_unsafe() {
if is_fn_unsafe_to_call(db, func) {
unsafe_expr_cb(UnsafeExpr { expr: current, inside_unsafe_block });
}
}
@ -79,7 +81,7 @@ fn walk_unsafe(
Expr::MethodCall { .. } => {
if infer
.method_resolution(current)
.map(|(func, _)| db.function_data(func).is_unsafe())
.map(|(func, _)| is_fn_unsafe_to_call(db, func))
.unwrap_or(false)
{
unsafe_expr_cb(UnsafeExpr { expr: current, inside_unsafe_block });

View file

@ -748,7 +748,7 @@ impl<'a> InferenceContext<'a> {
self.infer_pat(*pat, &ty, BindingMode::default());
}
let error_ty = &TypeRef::Error;
let return_ty = if data.is_async() {
let return_ty = if data.has_async_kw() {
data.async_ret_type.as_deref().unwrap_or(error_ty)
} else {
&*data.ret_type

View file

@ -64,7 +64,7 @@ pub use mapping::{
to_placeholder_idx,
};
pub use traits::TraitEnvironment;
pub use utils::all_super_traits;
pub use utils::{all_super_traits, is_fn_unsafe_to_call};
pub use walk::TypeWalk;
pub use chalk_ir::{

View file

@ -15,10 +15,10 @@ use hir_def::{
path::Path,
resolver::{HasResolver, TypeNs},
type_ref::{TraitBoundModifier, TypeRef},
ConstParamId, GenericDefId, ItemContainerId, Lookup, TraitId, TypeAliasId, TypeOrConstParamId,
TypeParamId,
ConstParamId, FunctionId, GenericDefId, ItemContainerId, Lookup, TraitId, TypeAliasId,
TypeOrConstParamId, TypeParamId,
};
use hir_expand::name::{name, Name};
use hir_expand::name::{known, name, Name};
use itertools::Either;
use rustc_hash::FxHashSet;
use smallvec::{smallvec, SmallVec};
@ -375,3 +375,66 @@ fn parent_generic_def(db: &dyn DefDatabase, def: GenericDefId) -> Option<Generic
ItemContainerId::ModuleId(_) | ItemContainerId::ExternBlockId(_) => None,
}
}
pub fn is_fn_unsafe_to_call(db: &dyn HirDatabase, func: FunctionId) -> bool {
let data = db.function_data(func);
if data.has_unsafe_kw() {
return true;
}
match func.lookup(db.upcast()).container {
hir_def::ItemContainerId::ExternBlockId(block) => {
// Function in an `extern` block are always unsafe to call, except when it has
// `"rust-intrinsic"` ABI there are a few exceptions.
let id = block.lookup(db.upcast()).id;
match id.item_tree(db.upcast())[id.value].abi.as_deref() {
Some("rust-intrinsic") => is_intrinsic_fn_unsafe(&data.name),
_ => true,
}
}
_ => false,
}
}
/// Returns `true` if the given intrinsic is unsafe to call, or false otherwise.
fn is_intrinsic_fn_unsafe(name: &Name) -> bool {
// Should be kept in sync with https://github.com/rust-lang/rust/blob/532d2b14c05f9bc20b2d27cbb5f4550d28343a36/compiler/rustc_typeck/src/check/intrinsic.rs#L72-L106
![
known::abort,
known::add_with_overflow,
known::bitreverse,
known::black_box,
known::bswap,
known::caller_location,
known::ctlz,
known::ctpop,
known::cttz,
known::discriminant_value,
known::forget,
known::likely,
known::maxnumf32,
known::maxnumf64,
known::min_align_of,
known::minnumf32,
known::minnumf64,
known::mul_with_overflow,
known::needs_drop,
known::ptr_guaranteed_eq,
known::ptr_guaranteed_ne,
known::rotate_left,
known::rotate_right,
known::rustc_peek,
known::saturating_add,
known::saturating_sub,
known::size_of,
known::sub_with_overflow,
known::type_id,
known::type_name,
known::unlikely,
known::variant_count,
known::wrapping_add,
known::wrapping_mul,
known::wrapping_sub,
]
.contains(name)
}

View file

@ -362,7 +362,7 @@ fn highlight_def(sema: &Semantics<RootDatabase>, krate: hir::Crate, def: Definit
}
}
if func.is_unsafe(db) {
if func.is_unsafe_to_call(db) {
h |= HlMod::Unsafe;
}
if func.is_async(db) {
@ -508,7 +508,7 @@ fn highlight_method_call(
let mut h = SymbolKind::Function.into();
h |= HlMod::Associated;
if func.is_unsafe(sema.db) || sema.is_unsafe_method_call(method_call) {
if func.is_unsafe_to_call(sema.db) || sema.is_unsafe_method_call(method_call) {
h |= HlMod::Unsafe;
}
if func.is_async(sema.db) {

View file

@ -237,7 +237,7 @@ fn detail(db: &dyn HirDatabase, func: hir::Function) -> String {
if func.is_async(db) {
format_to!(detail, "async ");
}
if func.is_unsafe(db) {
if func.is_unsafe_to_call(db) {
format_to!(detail, "unsafe ");
}