carbon-language/carbon-lang
1
0
Fork 0
mirror of https://github.com/carbon-language/carbon-lang.git synced 2026-10-04 22:02:52 +01:00
Code Issues Packages Projects Releases 10 Wiki Activity

Diagnose impl method without matching virtual function in base class (#5817)

Browse Source 
Also update `RequestVtableIfVirtual` to strip `impl` from functions in
classes without a base class - this avoids a duplicate diagnostic where
they're diagnosed as being in a class without a base class, then
diagnosed again because they don't have a matching function in a base
class.
This commit is contained in:
David Blaikie
2025-07-18 19:03:06 +00:00
committed by GitHub
parent 8428b86cfb
commit 37ac093f32
4 changed files with 26 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files
toolchain/check/class.cpp
+9 -2
View File
@@ -169,6 +169,7 @@ static auto BuildVtable(Context& context, Parse::ClassDefinitionId node_id,
};
llvm::SmallVector<SemIR::InstId> vtable;
Set<SemIR::FunctionId> implemented_impls;
if (base_vtable_id.has_value()) {
auto base_vtable_inst_block = context.inst_blocks().Get(
context.vtables().Get(base_vtable_id).virtual_functions_id);
@@ -190,8 +191,10 @@ static auto BuildVtable(Context& context, Parse::ClassDefinitionId node_id,
override_fn.name_id == fn.name_id;
});
if (i != vtable_contents.end()) {
auto& override_fn = context.functions().Get(
context.insts().GetAs<SemIR::FunctionDecl>(*i).function_id);
auto override_fn_id =
context.insts().GetAs<SemIR::FunctionDecl>(*i).function_id;
implemented_impls.Insert(override_fn_id);
auto& override_fn = context.functions().Get(override_fn_id);
CheckFunctionTypeMatches(context, override_fn, fn, specific_id,
/*check_syntax=*/false,
/*check_self=*/false);
@@ -209,6 +212,10 @@ static auto BuildVtable(Context& context, Parse::ClassDefinitionId node_id,
if (fn.virtual_modifier != SemIR::FunctionFields::VirtualModifier::Impl) {
fn.virtual_index = vtable.size();
vtable.push_back(build_specific_function(inst_id));
} else if (!implemented_impls.Lookup(fn_decl.function_id)) {
CARBON_DIAGNOSTIC(ImplWithoutVirtualInBase, Error,
"impl without compatible virtual in base class");
context.emitter().Emit(SemIR::LocId(inst_id), ImplWithoutVirtualInBase);
}
}
toolchain/check/handle_function.cpp
+6 -3
View File
@@ -327,7 +327,7 @@ static auto IsGenericFunction(Context& context,
// Requests a vtable be created when processing a virtual function.
static auto RequestVtableIfVirtual(
Context& context, Parse::AnyFunctionDeclId node_id,
SemIR::Function::VirtualModifier virtual_modifier,
SemIR::Function::VirtualModifier& virtual_modifier,
const std::optional<SemIR::Inst>& parent_scope_inst, SemIR::InstId decl_id,
SemIR::GenericId generic_id) -> void {
// In order to request a vtable, the function must be virtual, and in a class
@@ -346,11 +346,14 @@ static auto RequestVtableIfVirtual(
!class_info.base_id.has_value()) {
CARBON_DIAGNOSTIC(ImplWithoutBase, Error, "impl without base class");
context.emitter().Emit(node_id, ImplWithoutBase);
virtual_modifier = SemIR::Function::VirtualModifier::None;
return;
}
if (IsGenericFunction(context, generic_id, class_info.generic_id)) {
CARBON_DIAGNOSTIC(GenericVirtual, Error, "generic virtual function");
context.emitter().Emit(node_id, GenericVirtual);
virtual_modifier = SemIR::Function::VirtualModifier::None;
return;
}
@@ -528,8 +531,8 @@ static auto BuildFunctionDecl(Context& context,
// TODO: Validate that the redeclaration doesn't set an access modifier.
}
RequestVtableIfVirtual(context, node_id, virtual_modifier, parent_scope_inst,
decl_id, function_info.generic_id);
RequestVtableIfVirtual(context, node_id, function_info.virtual_modifier,
parent_scope_inst, decl_id, function_info.generic_id);
// Write the function ID into the FunctionDecl.
ReplaceInstBeforeConstantUse(context, decl_id, function_decl);
toolchain/check/testdata/class/virtual_modifiers.carbon
Vendored
+10 -12
View File
@@ -130,7 +130,7 @@ fn F() {
b1.m2 = 4;
}
// --- todo_fail_impl_without_base_declaration.carbon
// --- fail_impl_without_base_declaration.carbon
library "[[@TEST_NAME]]";
@@ -139,6 +139,10 @@ base class Base {
class Derived {
extend base: Base;
// CHECK:STDERR: fail_impl_without_base_declaration.carbon:[[@LINE+4]]:3: error: impl without compatible virtual in base class [ImplWithoutVirtualInBase]
// CHECK:STDERR: impl fn F[self: Self]();
// CHECK:STDERR: ^~~~~~~~~~~~~~~~~~~~~~~~
// CHECK:STDERR:
impl fn F[self: Self]();
}
@@ -1252,10 +1256,8 @@ var v: Base(T1) = {};
// CHECK:STDOUT: %pattern_type: type = pattern_type %C [concrete]
// CHECK:STDOUT: %F.type: type = fn_type @F [concrete]
// CHECK:STDOUT: %F: %F.type = struct_value () [concrete]
// CHECK:STDOUT: %ptr: type = ptr_type <vtable> [concrete]
// CHECK:STDOUT: %C.vtable_ptr: ref %ptr = vtable_ptr @C.vtable [concrete]
// CHECK:STDOUT: %struct_type.vptr: type = struct_type {.<vptr>: %ptr} [concrete]
// CHECK:STDOUT: %complete_type: <witness> = complete_type_witness %struct_type.vptr [concrete]
// CHECK:STDOUT: %empty_struct_type: type = struct_type {} [concrete]
// CHECK:STDOUT: %complete_type: <witness> = complete_type_witness %empty_struct_type [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
@@ -1283,19 +1285,15 @@ var v: Base(T1) = {};
// CHECK:STDOUT: %Self.ref: type = name_ref Self, constants.%C [concrete = constants.%C]
// CHECK:STDOUT: %self: %C = bind_name self, %self.param
// CHECK:STDOUT: }
// CHECK:STDOUT: %vtable_ptr: ref %ptr = vtable_ptr @C.vtable [concrete = constants.%C.vtable_ptr]
// CHECK:STDOUT: %struct_type.vptr: type = struct_type {.<vptr>: %ptr} [concrete = constants.%struct_type.vptr]
// CHECK:STDOUT: %complete_type: <witness> = complete_type_witness %struct_type.vptr [concrete = constants.%complete_type]
// CHECK:STDOUT: %empty_struct_type: type = struct_type {} [concrete = constants.%empty_struct_type]
// CHECK:STDOUT: %complete_type: <witness> = complete_type_witness %empty_struct_type [concrete = constants.%complete_type]
// CHECK:STDOUT: complete_type_witness = %complete_type
// CHECK:STDOUT: vtable_ptr = %vtable_ptr
// CHECK:STDOUT:
// CHECK:STDOUT: !members:
// CHECK:STDOUT: .Self = constants.%C
// CHECK:STDOUT: .F = %F.decl
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: vtable @C.vtable {}
// CHECK:STDOUT:
// CHECK:STDOUT: impl fn @F(%self.param: %C);
// CHECK:STDOUT:
// CHECK:STDOUT: --- init_members.carbon
@@ -1518,7 +1516,7 @@ var v: Base(T1) = {};
// CHECK:STDOUT: return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- todo_fail_impl_without_base_declaration.carbon
// CHECK:STDOUT: --- fail_impl_without_base_declaration.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT: %Base: type = class_type @Base [concrete]
toolchain/diagnostics/diagnostic_kind.def
+1
View File
@@ -269,6 +269,7 @@ CARBON_DIAGNOSTIC_KIND(ClassSpecificDeclPrevious)
CARBON_DIAGNOSTIC_KIND(ClassIncompleteWithinDefinition)
CARBON_DIAGNOSTIC_KIND(GenericVirtual)
CARBON_DIAGNOSTIC_KIND(ImplWithoutBase)
CARBON_DIAGNOSTIC_KIND(ImplWithoutVirtualInBase)
CARBON_DIAGNOSTIC_KIND(VirtualWithoutSelf)
// Deduction.