Skip to content

Forbid types with const generics on configurables #7494

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 3 commits into
base: master
Choose a base branch
from
Open

Forbid types with const generics on configurables #7494

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
4c9ed33
forbid types with const generics on configurables
xunilrj Nov 13, 2025
d6514cb
fmt and clippy issues
xunilrj Nov 13, 2025
eb61590
Merge branch 'master' into xunilrj/forbid-const-generics-configurables
JoshuaBatty Nov 20, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
73 changes: 4 additions & 69 deletions sway-core/src/language/ty/declaration/abi.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,6 +1,5 @@
use super::{TyDeclParsedType, TyTraitInterfaceItem, TyTraitItem};
use crate::{
ast_elements::type_parameter::ConstGenericExpr,
decl_engine::DeclEngineGet as _,
engine_threading::*,
language::parsed::{self, AbiDeclaration},
Expand Down Expand Up @@ -29,70 +28,6 @@ pub struct TyAbiDecl {
pub attributes: transform::Attributes,
}

fn has_const_generics(type_id: TypeId, engines: &Engines) -> bool {
let types = type_id.extract_any_including_self(engines, &|_| true, vec![], 0);

for (t, _) in types {
let t = engines.te().get(t);
match &*t {
TypeInfo::StringArray(length) => match length.expr() {
ConstGenericExpr::Literal { .. } => {}
ConstGenericExpr::AmbiguousVariableExpression { .. } => return true,
},
TypeInfo::Enum(decl_id) => {
let decl = engines.de().get(decl_id);
let any_const_generics = decl
.generic_parameters
.iter()
.any(|x| x.as_const_parameter().is_some());
if any_const_generics {
return true;
}
}
TypeInfo::Struct(decl_id) => {
let decl = engines.de().get(decl_id);
let any_const_generics = decl
.generic_parameters
.iter()
.any(|x| x.as_const_parameter().is_some());
if any_const_generics {
return true;
}

for field in decl.fields.iter() {
let any_const_generics =
has_const_generics(field.type_argument.type_id, engines);
if any_const_generics {
return true;
}
}
}
TypeInfo::Tuple(items) => {
for item in items {
let any_const_generics = has_const_generics(item.type_id, engines);
if any_const_generics {
return true;
}
}
}
TypeInfo::Array(item, length) => {
let any_const_generics = has_const_generics(item.type_id, engines);
if any_const_generics {
return true;
}

match length.expr() {
ConstGenericExpr::Literal { .. } => {}
ConstGenericExpr::AmbiguousVariableExpression { .. } => return true,
}
}
_ => {}
}
}

false
}

impl TyAbiDecl {
pub(crate) fn forbid_const_generics(
&self,
Expand All @@ -104,15 +39,15 @@ impl TyAbiDecl {
TyTraitInterfaceItem::TraitFn(decl_ref) => {
let decl = engines.de().get(decl_ref.id());

if has_const_generics(decl.return_type.type_id, engines) {
if decl.return_type.type_id.has_const_generics(engines) {
let err = handler.emit_err(CompileError::ConstGenericNotSupportedHere {
span: decl.return_type.span(),
});
return Err(err);
}

for arg in decl.parameters.iter() {
if has_const_generics(arg.type_argument.type_id, engines) {
if arg.type_argument.type_id.has_const_generics(engines) {
let err =
handler.emit_err(CompileError::ConstGenericNotSupportedHere {
span: arg.type_argument.span.clone(),
Expand All @@ -130,15 +65,15 @@ impl TyAbiDecl {
match item {
TyTraitItem::Fn(decl_ref) => {
let decl = engines.de().get(decl_ref.id());
if has_const_generics(decl.return_type.type_id, engines) {
if decl.return_type.type_id.has_const_generics(engines) {
let err = handler.emit_err(CompileError::ConstGenericNotSupportedHere {
span: decl.return_type.span(),
});
return Err(err);
}

for arg in decl.parameters.iter() {
if has_const_generics(arg.type_argument.type_id, engines) {
if arg.type_argument.type_id.has_const_generics(engines) {
let err =
handler.emit_err(CompileError::ConstGenericNotSupportedHere {
span: arg.type_argument.span.clone(),
Expand Down
16 changes: 16 additions & 0 deletions sway-core/src/semantic_analysis/ast_node/declaration/configurable.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -188,6 +188,22 @@ impl ty::TyConfigurableDecl {
visibility,
})
}

pub(crate) fn forbid_const_generics(
&self,
handler: &Handler,
engines: &Engines,
) -> Result<(), ErrorEmitted> {
if self.type_ascription.type_id.has_const_generics(engines) {
Err(
handler.emit_err(CompileError::ConstGenericNotSupportedHere {
span: self.type_ascription.span.clone(),
}),
)
} else {
Ok(())
}
}
}

impl TypeCheckAnalysis for TyConfigurableDecl {
Expand Down
7 changes: 4 additions & 3 deletions sway-core/src/semantic_analysis/ast_node/declaration/declaration.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -120,9 +120,10 @@ impl TyDecl {
let name = decl.name.clone();
let typed_const_decl =
match ty::TyConfigurableDecl::type_check(handler, ctx.by_ref(), decl) {
Ok(config_decl) => ty::TyDecl::from(
decl_engine.insert(config_decl.clone(), Some(&decl_id)),
),
Ok(config_decl) => {
config_decl.forbid_const_generics(handler, engines)?;
ty::TyDecl::from(decl_engine.insert(config_decl, Some(&decl_id)))
}
Err(err) => ty::TyDecl::ErrorRecovery(span, err),
};
ctx.insert_symbol(handler, name, typed_const_decl.clone())?;
Expand Down
64 changes: 64 additions & 0 deletions sway-core/src/type_system/id.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1484,4 +1484,68 @@ impl TypeId {
pub fn get_type_str(&self, engines: &Engines) -> String {
engines.te().get(*self).get_type_str(engines)
}

pub fn has_const_generics(&self, engines: &Engines) -> bool {
let types = self.extract_any_including_self(engines, &|_| true, vec![], 0);

for (t, _) in types {
let t = engines.te().get(t);
match &*t {
TypeInfo::StringArray(length) => match length.expr() {
ConstGenericExpr::Literal { .. } => {}
ConstGenericExpr::AmbiguousVariableExpression { .. } => return true,
},
TypeInfo::Enum(decl_id) => {
let decl = engines.de().get(decl_id);
let any_const_generics = decl
.generic_parameters
.iter()
.any(|x| x.as_const_parameter().is_some());
if any_const_generics {
return true;
}
}
TypeInfo::Struct(decl_id) => {
let decl = engines.de().get(decl_id);
let any_const_generics = decl
.generic_parameters
.iter()
.any(|x| x.as_const_parameter().is_some());
if any_const_generics {
return true;
}

for field in decl.fields.iter() {
let any_const_generics =
field.type_argument.type_id.has_const_generics(engines);
if any_const_generics {
return true;
}
}
}
TypeInfo::Tuple(items) => {
for item in items {
let any_const_generics = item.type_id.has_const_generics(engines);
if any_const_generics {
return true;
}
}
}
TypeInfo::Array(item, length) => {
let any_const_generics = item.type_id.has_const_generics(engines);
if any_const_generics {
return true;
}

match length.expr() {
ConstGenericExpr::Literal { .. } => {}
ConstGenericExpr::AmbiguousVariableExpression { .. } => return true,
}
}
_ => {}
}
}

false
}
}
8 changes: 8 additions & 0 deletions test/src/e2e_vm_tests/test_programs/should_fail/unsupported_const_generics/src/main.sw
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -42,6 +42,8 @@ impl<const N: u64> A for CrazyEnum<N> {
}
}

// abi cannot have const generics

abi NoConstGenericsOnArgs {
fn f(a: CrazyStruct<1>);
}
Expand All @@ -66,6 +68,12 @@ abi NoConstGenericsIndirectEnum {
fn f() -> EnumWithConstGenericInside;
}

// configurable cannot have const generics

configurable {
A: CrazyStruct<1> = CrazyStruct { },
}

fn main() {
let _: CrazyStruct<UNKNOWN> = CrazyStruct { };
let _: CrazyEnum<UNKNOWN> = CrazyEnum::A;
Expand Down
Loading
Loading