Implement support for mixed-access overload sets. (#6137)

This turns out to be quite important, as several important standard
library types (such as `std::string`) have mixed-access overload sets
for their constructors as an implementation detail. The overall approach
here is:

- Use the most permissive access to determine the access of the overload
set itself. This affects whether name lookup finds the member name at
all.
- After overload resolution, re-check the access of the selected member,
if it's protected or private.

---------

Co-authored-by: Dana Jansens <danakj@orodu.net>
This commit is contained in:
Richard Smith
2025-09-26 23:18:16 +00:00
committed by GitHub
co-authored by Dana Jansens
parent 83ba714165
commit 3b6d202730
11 changed files with 238 additions and 332 deletions
@@ -238,54 +238,6 @@ fn F() {
Cpp.foo(1 as i32);
}
// ============================================================================
// Overloads access
// ============================================================================
// --- same_access_level.h
struct S {
public:
static auto foo(short a) -> void;
static auto foo(int a) -> void;
};
// --- import_same_access_level.carbon
library "[[@TEST_NAME]]";
import Cpp library "same_access_level.h";
fn F() {
Cpp.S.foo(1 as i32);
}
// --- mixed_access_level.h
struct S {
public:
static auto foo(int a) -> void;
protected:
static auto foo(short a) -> void;
};
// --- fail_todo_import_mixed_access_level.carbon
library "[[@TEST_NAME]]";
import Cpp library "mixed_access_level.h";
fn F() {
// CHECK:STDERR: fail_todo_import_mixed_access_level.carbon:[[@LINE+7]]:3: error: semantics TODO: `Unsupported: Overloaded set with mixed access` [SemanticsTodo]
// CHECK:STDERR: Cpp.S.foo(1 as i32);
// CHECK:STDERR: ^~~~~~~~~
// CHECK:STDERR: fail_todo_import_mixed_access_level.carbon:[[@LINE+4]]:3: note: in `Cpp` name lookup for `foo` [InCppNameLookup]
// CHECK:STDERR: Cpp.S.foo(1 as i32);
// CHECK:STDERR: ^~~~~~~~~
// CHECK:STDERR:
Cpp.S.foo(1 as i32);
}
// ============================================================================
// No viable function found
// ============================================================================
@@ -1671,207 +1623,6 @@ fn F() {
// CHECK:STDOUT:
// CHECK:STDOUT: fn @foo__carbon_thunk(%a.param: %ptr);
// CHECK:STDOUT:
// CHECK:STDOUT: --- import_same_access_level.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT: %F.type: type = fn_type @F [concrete]
// CHECK:STDOUT: %empty_tuple.type: type = tuple_type () [concrete]
// CHECK:STDOUT: %F: %F.type = struct_value () [concrete]
// CHECK:STDOUT: %S: type = class_type @S [concrete]
// CHECK:STDOUT: %empty_struct_type: type = struct_type {} [concrete]
// CHECK:STDOUT: %complete_type.357: <witness> = complete_type_witness %empty_struct_type [concrete]
// CHECK:STDOUT: %.177: type = cpp_overload_set_type @As.Convert [concrete]
// CHECK:STDOUT: %empty_struct: %.177 = struct_value () [concrete]
// CHECK:STDOUT: %int_1.5b8: Core.IntLiteral = int_value 1 [concrete]
// CHECK:STDOUT: %int_32: Core.IntLiteral = int_value 32 [concrete]
// CHECK:STDOUT: %Int.type: type = generic_class_type @Int [concrete]
// CHECK:STDOUT: %Int.generic: %Int.type = struct_value () [concrete]
// CHECK:STDOUT: %i32: type = class_type @Int, @Int(%int_32) [concrete]
// CHECK:STDOUT: %As.type.90f: type = generic_interface_type @As [concrete]
// CHECK:STDOUT: %As.generic: %As.type.90f = struct_value () [concrete]
// CHECK:STDOUT: %As.type.dbd: type = facet_type <@As, @As(%i32)> [concrete]
// CHECK:STDOUT: %As.Convert.type.99b: type = fn_type @As.Convert, @As(%i32) [concrete]
// CHECK:STDOUT: %To: Core.IntLiteral = bind_symbolic_name To, 0 [symbolic]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.type.565: type = fn_type @Core.IntLiteral.as.As.impl.Convert, @Core.IntLiteral.as.As.impl(%To) [symbolic]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.d2c: %Core.IntLiteral.as.As.impl.Convert.type.565 = struct_value () [symbolic]
// CHECK:STDOUT: %As.impl_witness.080: <witness> = impl_witness imports.%As.impl_witness_table.5ad, @Core.IntLiteral.as.As.impl(%int_32) [concrete]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.type.aaf: type = fn_type @Core.IntLiteral.as.As.impl.Convert, @Core.IntLiteral.as.As.impl(%int_32) [concrete]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.414: %Core.IntLiteral.as.As.impl.Convert.type.aaf = struct_value () [concrete]
// CHECK:STDOUT: %As.facet: %As.type.dbd = facet_value Core.IntLiteral, (%As.impl_witness.080) [concrete]
// CHECK:STDOUT: %.351: type = fn_type_with_self_type %As.Convert.type.99b, %As.facet [concrete]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.bound: <bound method> = bound_method %int_1.5b8, %Core.IntLiteral.as.As.impl.Convert.414 [concrete]
// CHECK:STDOUT: %pattern_type.7ce: type = pattern_type %i32 [concrete]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.specific_fn: <specific function> = specific_function %Core.IntLiteral.as.As.impl.Convert.414, @Core.IntLiteral.as.As.impl.Convert(%int_32) [concrete]
// CHECK:STDOUT: %bound_method: <bound method> = bound_method %int_1.5b8, %Core.IntLiteral.as.As.impl.Convert.specific_fn [concrete]
// CHECK:STDOUT: %int_1.5d2: %i32 = int_value 1 [concrete]
// CHECK:STDOUT: %S.foo.type: type = fn_type @S.foo [concrete]
// CHECK:STDOUT: %S.foo: %S.foo.type = struct_value () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT: %Core: <namespace> = namespace file.%Core.import, [concrete] {
// CHECK:STDOUT: .Int = %Core.Int
// CHECK:STDOUT: .As = %Core.As
// CHECK:STDOUT: import Core//prelude
// CHECK:STDOUT: import Core//prelude/...
// CHECK:STDOUT: }
// CHECK:STDOUT: %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT: .S = %S.decl
// CHECK:STDOUT: import Cpp//...
// CHECK:STDOUT: }
// CHECK:STDOUT: %S.decl: type = class_decl @S [concrete = constants.%S] {} {}
// CHECK:STDOUT: %.dcb: %.177 = cpp_overload_set_value @As.Convert [concrete = constants.%empty_struct]
// CHECK:STDOUT: %Core.Int: %Int.type = import_ref Core//prelude/parts/int, Int, loaded [concrete = constants.%Int.generic]
// CHECK:STDOUT: %Core.As: %As.type.90f = import_ref Core//prelude/parts/as, As, loaded [concrete = constants.%As.generic]
// CHECK:STDOUT: %Core.import_ref.99c: @Core.IntLiteral.as.As.impl.%Core.IntLiteral.as.As.impl.Convert.type (%Core.IntLiteral.as.As.impl.Convert.type.565) = import_ref Core//prelude/parts/int, loc32_39, loaded [symbolic = @Core.IntLiteral.as.As.impl.%Core.IntLiteral.as.As.impl.Convert (constants.%Core.IntLiteral.as.As.impl.Convert.d2c)]
// CHECK:STDOUT: %As.impl_witness_table.5ad = impl_witness_table (%Core.import_ref.99c), @Core.IntLiteral.as.As.impl [concrete]
// CHECK:STDOUT: %S.foo.decl: %S.foo.type = fn_decl @S.foo [concrete = constants.%S.foo] {
// CHECK:STDOUT: %a.patt: %pattern_type.7ce = binding_pattern a [concrete]
// CHECK:STDOUT: %a.param_patt: %pattern_type.7ce = value_param_pattern %a.patt, call_param0 [concrete]
// CHECK:STDOUT: } {
// CHECK:STDOUT: %a.param: %i32 = value_param call_param0
// CHECK:STDOUT: %.1: type = splice_block %i32 [concrete = constants.%i32] {
// CHECK:STDOUT: %int_32: Core.IntLiteral = int_value 32 [concrete = constants.%int_32]
// CHECK:STDOUT: %i32: type = class_type @Int, @Int(constants.%int_32) [concrete = constants.%i32]
// CHECK:STDOUT: }
// CHECK:STDOUT: %a: %i32 = bind_name a, %a.param
// CHECK:STDOUT: }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT: package: <namespace> = namespace [concrete] {
// CHECK:STDOUT: .Core = imports.%Core
// CHECK:STDOUT: .Cpp = imports.%Cpp
// CHECK:STDOUT: .F = %F.decl
// CHECK:STDOUT: }
// CHECK:STDOUT: %Core.import = import Core
// CHECK:STDOUT: %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT: import Cpp "same_access_level.h"
// CHECK:STDOUT: }
// CHECK:STDOUT: %F.decl: %F.type = fn_decl @F [concrete = constants.%F] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: class @S {
// 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.357]
// CHECK:STDOUT: complete_type_witness = %complete_type
// CHECK:STDOUT:
// CHECK:STDOUT: !members:
// CHECK:STDOUT: .foo = imports.%.dcb
// CHECK:STDOUT: import Cpp//...
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT: %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT: %S.ref: type = name_ref S, imports.%S.decl [concrete = constants.%S]
// CHECK:STDOUT: %foo.ref: %.177 = name_ref foo, imports.%.dcb [concrete = constants.%empty_struct]
// CHECK:STDOUT: %int_1: Core.IntLiteral = int_value 1 [concrete = constants.%int_1.5b8]
// CHECK:STDOUT: %int_32: Core.IntLiteral = int_value 32 [concrete = constants.%int_32]
// CHECK:STDOUT: %i32: type = class_type @Int, @Int(constants.%int_32) [concrete = constants.%i32]
// CHECK:STDOUT: %impl.elem0: %.351 = impl_witness_access constants.%As.impl_witness.080, element0 [concrete = constants.%Core.IntLiteral.as.As.impl.Convert.414]
// CHECK:STDOUT: %bound_method.loc7_15.1: <bound method> = bound_method %int_1, %impl.elem0 [concrete = constants.%Core.IntLiteral.as.As.impl.Convert.bound]
// CHECK:STDOUT: %specific_fn: <specific function> = specific_function %impl.elem0, @Core.IntLiteral.as.As.impl.Convert(constants.%int_32) [concrete = constants.%Core.IntLiteral.as.As.impl.Convert.specific_fn]
// CHECK:STDOUT: %bound_method.loc7_15.2: <bound method> = bound_method %int_1, %specific_fn [concrete = constants.%bound_method]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.call: init %i32 = call %bound_method.loc7_15.2(%int_1) [concrete = constants.%int_1.5d2]
// CHECK:STDOUT: %.loc7_15.1: %i32 = value_of_initializer %Core.IntLiteral.as.As.impl.Convert.call [concrete = constants.%int_1.5d2]
// CHECK:STDOUT: %.loc7_15.2: %i32 = converted %int_1, %.loc7_15.1 [concrete = constants.%int_1.5d2]
// CHECK:STDOUT: %S.foo.call: init %empty_tuple.type = call imports.%S.foo.decl(%.loc7_15.2)
// CHECK:STDOUT: return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @S.foo(%a.param: %i32);
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_todo_import_mixed_access_level.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT: %F.type: type = fn_type @F [concrete]
// CHECK:STDOUT: %F: %F.type = struct_value () [concrete]
// CHECK:STDOUT: %S: type = class_type @S [concrete]
// CHECK:STDOUT: %empty_struct_type: type = struct_type {} [concrete]
// CHECK:STDOUT: %complete_type.357: <witness> = complete_type_witness %empty_struct_type [concrete]
// CHECK:STDOUT: %int_1.5b8: Core.IntLiteral = int_value 1 [concrete]
// CHECK:STDOUT: %int_32: Core.IntLiteral = int_value 32 [concrete]
// CHECK:STDOUT: %Int.type: type = generic_class_type @Int [concrete]
// CHECK:STDOUT: %Int.generic: %Int.type = struct_value () [concrete]
// CHECK:STDOUT: %i32: type = class_type @Int, @Int(%int_32) [concrete]
// CHECK:STDOUT: %As.type.90f: type = generic_interface_type @As [concrete]
// CHECK:STDOUT: %As.generic: %As.type.90f = struct_value () [concrete]
// CHECK:STDOUT: %As.type.dbd: type = facet_type <@As, @As(%i32)> [concrete]
// CHECK:STDOUT: %As.Convert.type.99b: type = fn_type @As.Convert, @As(%i32) [concrete]
// CHECK:STDOUT: %To: Core.IntLiteral = bind_symbolic_name To, 0 [symbolic]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.type.565: type = fn_type @Core.IntLiteral.as.As.impl.Convert, @Core.IntLiteral.as.As.impl(%To) [symbolic]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.d2c: %Core.IntLiteral.as.As.impl.Convert.type.565 = struct_value () [symbolic]
// CHECK:STDOUT: %As.impl_witness.080: <witness> = impl_witness imports.%As.impl_witness_table.5ad, @Core.IntLiteral.as.As.impl(%int_32) [concrete]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.type.aaf: type = fn_type @Core.IntLiteral.as.As.impl.Convert, @Core.IntLiteral.as.As.impl(%int_32) [concrete]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.414: %Core.IntLiteral.as.As.impl.Convert.type.aaf = struct_value () [concrete]
// CHECK:STDOUT: %As.facet: %As.type.dbd = facet_value Core.IntLiteral, (%As.impl_witness.080) [concrete]
// CHECK:STDOUT: %.351: type = fn_type_with_self_type %As.Convert.type.99b, %As.facet [concrete]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.bound: <bound method> = bound_method %int_1.5b8, %Core.IntLiteral.as.As.impl.Convert.414 [concrete]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.specific_fn: <specific function> = specific_function %Core.IntLiteral.as.As.impl.Convert.414, @Core.IntLiteral.as.As.impl.Convert(%int_32) [concrete]
// CHECK:STDOUT: %bound_method: <bound method> = bound_method %int_1.5b8, %Core.IntLiteral.as.As.impl.Convert.specific_fn [concrete]
// CHECK:STDOUT: %int_1.5d2: %i32 = int_value 1 [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT: %Core: <namespace> = namespace file.%Core.import, [concrete] {
// CHECK:STDOUT: .Int = %Core.Int
// CHECK:STDOUT: .As = %Core.As
// CHECK:STDOUT: import Core//prelude
// CHECK:STDOUT: import Core//prelude/...
// CHECK:STDOUT: }
// CHECK:STDOUT: %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT: .S = %S.decl
// CHECK:STDOUT: import Cpp//...
// CHECK:STDOUT: }
// CHECK:STDOUT: %S.decl: type = class_decl @S [concrete = constants.%S] {} {}
// CHECK:STDOUT: %Core.Int: %Int.type = import_ref Core//prelude/parts/int, Int, loaded [concrete = constants.%Int.generic]
// CHECK:STDOUT: %Core.As: %As.type.90f = import_ref Core//prelude/parts/as, As, loaded [concrete = constants.%As.generic]
// CHECK:STDOUT: %Core.import_ref.99c: @Core.IntLiteral.as.As.impl.%Core.IntLiteral.as.As.impl.Convert.type (%Core.IntLiteral.as.As.impl.Convert.type.565) = import_ref Core//prelude/parts/int, loc32_39, loaded [symbolic = @Core.IntLiteral.as.As.impl.%Core.IntLiteral.as.As.impl.Convert (constants.%Core.IntLiteral.as.As.impl.Convert.d2c)]
// CHECK:STDOUT: %As.impl_witness_table.5ad = impl_witness_table (%Core.import_ref.99c), @Core.IntLiteral.as.As.impl [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT: package: <namespace> = namespace [concrete] {
// CHECK:STDOUT: .Core = imports.%Core
// CHECK:STDOUT: .Cpp = imports.%Cpp
// CHECK:STDOUT: .F = %F.decl
// CHECK:STDOUT: }
// CHECK:STDOUT: %Core.import = import Core
// CHECK:STDOUT: %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT: import Cpp "mixed_access_level.h"
// CHECK:STDOUT: }
// CHECK:STDOUT: %F.decl: %F.type = fn_decl @F [concrete = constants.%F] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: class @S {
// 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.357]
// CHECK:STDOUT: complete_type_witness = %complete_type
// CHECK:STDOUT:
// CHECK:STDOUT: !members:
// CHECK:STDOUT: .foo = <poisoned>
// CHECK:STDOUT: import Cpp//...
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT: %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT: %S.ref: type = name_ref S, imports.%S.decl [concrete = constants.%S]
// CHECK:STDOUT: %foo.ref: <error> = name_ref foo, <error> [concrete = <error>]
// CHECK:STDOUT: %int_1: Core.IntLiteral = int_value 1 [concrete = constants.%int_1.5b8]
// CHECK:STDOUT: %int_32: Core.IntLiteral = int_value 32 [concrete = constants.%int_32]
// CHECK:STDOUT: %i32: type = class_type @Int, @Int(constants.%int_32) [concrete = constants.%i32]
// CHECK:STDOUT: %impl.elem0: %.351 = impl_witness_access constants.%As.impl_witness.080, element0 [concrete = constants.%Core.IntLiteral.as.As.impl.Convert.414]
// CHECK:STDOUT: %bound_method.loc14_15.1: <bound method> = bound_method %int_1, %impl.elem0 [concrete = constants.%Core.IntLiteral.as.As.impl.Convert.bound]
// CHECK:STDOUT: %specific_fn: <specific function> = specific_function %impl.elem0, @Core.IntLiteral.as.As.impl.Convert(constants.%int_32) [concrete = constants.%Core.IntLiteral.as.As.impl.Convert.specific_fn]
// CHECK:STDOUT: %bound_method.loc14_15.2: <bound method> = bound_method %int_1, %specific_fn [concrete = constants.%bound_method]
// CHECK:STDOUT: %Core.IntLiteral.as.As.impl.Convert.call: init %i32 = call %bound_method.loc14_15.2(%int_1) [concrete = constants.%int_1.5d2]
// CHECK:STDOUT: %.loc14_15.1: %i32 = value_of_initializer %Core.IntLiteral.as.As.impl.Convert.call [concrete = constants.%int_1.5d2]
// CHECK:STDOUT: %.loc14_15.2: %i32 = converted %int_1, %.loc14_15.1 [concrete = constants.%int_1.5d2]
// CHECK:STDOUT: return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_import_no_viable_function.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {