From 35c90fe12413335962cad02d77a4894079b00a5d Mon Sep 17 00:00:00 2001 From: gingerBill Date: Thu, 3 Feb 2022 13:34:31 +0000 Subject: Fix type alias declaration evaluation problem (#854 #1439) --- src/check_decl.cpp | 39 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 38 insertions(+), 1 deletion(-) (limited to 'src/check_decl.cpp') diff --git a/src/check_decl.cpp b/src/check_decl.cpp index f9bc17ba4..193c28aea 100644 --- a/src/check_decl.cpp +++ b/src/check_decl.cpp @@ -385,7 +385,44 @@ void check_const_decl(CheckerContext *ctx, Entity *e, Ast *type_expr, Ast *init, Operand operand = {}; if (init != nullptr) { - Entity *entity = nullptr; + Entity *entity = check_entity_from_ident_or_selector(ctx, init); + if (entity != nullptr && entity->kind == Entity_TypeName) { + // NOTE(bill, 2022-02-03): This is used to solve the problem caused by type aliases + // being "confused" as constants + // + // A :: B + // C :: proc "c" (^A) + // B :: struct {x: C} + // + // A gets evaluated first, and then checks B. + // B then checks C. + // C then tries to check A which is unresolved but thought to be a constant. + // Therefore within C's check, A errs as "not a type". + // + // This is because a const declaration may or may not be a type and this cannot + // be determined from a syntactical standpoint. + // This check allows the compiler to override the entity to be checked as a type. + // + // There is no problem if B is prefixed with the `#type` helper enforcing at + // both a syntax and semantic level that B must be a type. + // + // A :: #type B + // + // This approach is not fool proof and can fail in case such as: + // + // X :: type_of(x) + // X :: Foo(int).Type + // + // Since even these kind of declarations may cause weird checking cycles. + // For the time being, these are going to be treated as an unfortunate error + // until there is a proper delaying system to try declaration again if they + // have failed. + + e->kind = Entity_TypeName; + check_type_decl(ctx, e, init, named_type); + return; + } + entity = nullptr; if (init->kind == Ast_Ident) { entity = check_ident(ctx, &operand, init, nullptr, e->type, true); } else if (init->kind == Ast_SelectorExpr) { -- cgit v1.2.3 From 3a81f2ab898d537bba51b9ea81e047652112574e Mon Sep 17 00:00:00 2001 From: gingerBill Date: Fri, 4 Feb 2022 22:40:15 +0000 Subject: Correct the type aliasing problem, caused by aliases (of aliases)+ --- src/check_decl.cpp | 1 + src/check_expr.cpp | 5 ++++- src/checker.cpp | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++++- 3 files changed, 70 insertions(+), 2 deletions(-) (limited to 'src/check_decl.cpp') diff --git a/src/check_decl.cpp b/src/check_decl.cpp index 193c28aea..2454feb33 100644 --- a/src/check_decl.cpp +++ b/src/check_decl.cpp @@ -387,6 +387,7 @@ void check_const_decl(CheckerContext *ctx, Entity *e, Ast *type_expr, Ast *init, if (init != nullptr) { Entity *entity = check_entity_from_ident_or_selector(ctx, init); if (entity != nullptr && entity->kind == Entity_TypeName) { + // @TypeAliasingProblem // NOTE(bill, 2022-02-03): This is used to solve the problem caused by type aliases // being "confused" as constants // diff --git a/src/check_expr.cpp b/src/check_expr.cpp index 88296611b..e1c9bde84 100644 --- a/src/check_expr.cpp +++ b/src/check_expr.cpp @@ -4088,7 +4088,7 @@ Entity *check_entity_from_ident_or_selector(CheckerContext *c, Ast *node) { return scope_lookup(c->scope, name); } else if (node->kind == Ast_SelectorExpr) { ast_node(se, SelectorExpr, node); - if (!c->allow_arrow_right_selector_expr && se->token.kind == Token_ArrowRight) { + if (se->token.kind == Token_ArrowRight) { return nullptr; } @@ -4108,6 +4108,9 @@ Entity *check_entity_from_ident_or_selector(CheckerContext *c, Ast *node) { if (op_expr->kind == Ast_Ident) { String op_name = op_expr->Ident.token.string; Entity *e = scope_lookup(c->scope, op_name); + if (e == nullptr) { + return nullptr; + } add_entity_use(c, op_expr, e); expr_entity = e; diff --git a/src/checker.cpp b/src/checker.cpp index c4423b2bc..c90f357dd 100644 --- a/src/checker.cpp +++ b/src/checker.cpp @@ -3665,6 +3665,59 @@ void check_add_foreign_block_decl(CheckerContext *ctx, Ast *decl) { check_collect_entities(&c, block->stmts); } +bool correct_single_type_alias(CheckerContext *c, Entity *e) { + if (e->kind == Entity_Constant) { + DeclInfo *d = e->decl_info; + if (d != nullptr && d->init_expr != nullptr) { + Ast *init = d->init_expr; + Entity *alias_of = check_entity_from_ident_or_selector(c, init); + if (alias_of != nullptr && alias_of->kind == Entity_TypeName) { + e->kind = Entity_TypeName; + return true; + } + } + } + return false; +} + +bool correct_type_alias_in_scope_backwards(CheckerContext *c, Scope *s) { + isize n = s->elements.entries.count; + bool correction = false; + for (isize i = n-1; i >= 0; i--) { + correction |= correct_single_type_alias(c, s->elements.entries[i].value); + } + return correction; +} +bool correct_type_alias_in_scope_forwards(CheckerContext *c, Scope *s) { + isize n = s->elements.entries.count; + bool correction = false; + for (isize i = 0; i < n; i++) { + correction |= correct_single_type_alias(c, s->elements.entries[i].value); + } + return correction; +} + + +void correct_type_aliases_in_scope(CheckerContext *c, Scope *s) { + // NOTE(bill, 2022-02-04): This is used to solve the problem caused by type aliases + // of type aliases being "confused" as constants + // + // A :: C + // B :: A + // C :: struct {b: ^B} + // + // See @TypeAliasingProblem for more information + for (;;) { + bool corrections = false; + corrections |= correct_type_alias_in_scope_backwards(c, s); + corrections |= correct_type_alias_in_scope_forwards(c, s); + if (!corrections) { + return; + } + } +} + + // NOTE(bill): If file_scopes == nullptr, this will act like a local scope void check_collect_entities(CheckerContext *c, Slice const &nodes) { AstFile *curr_file = nullptr; @@ -3736,6 +3789,7 @@ void check_collect_entities(CheckerContext *c, Slice const &nodes) { } } + // correct_type_aliases(c); // NOTE(bill): 'when' stmts need to be handled after the other as the condition may refer to something // declared after this stmt in source @@ -4381,10 +4435,11 @@ bool collect_file_decls(CheckerContext *ctx, Slice const &decls) { for_array(i, decls) { if (collect_file_decl(ctx, decls[i])) { + correct_type_aliases_in_scope(ctx, ctx->scope); return true; } } - + correct_type_aliases_in_scope(ctx, ctx->scope); return false; } @@ -4654,6 +4709,15 @@ void check_import_entities(Checker *c) { } add_untyped_expressions(ctx.info, &untyped); } + + for_array(i, pkg->files) { + AstFile *f = pkg->files[i]; + reset_checker_context(&ctx, f, &untyped); + ctx.collect_delayed_decls = false; + + correct_type_aliases_in_scope(&ctx, pkg->scope); + } + for_array(i, pkg->files) { AstFile *f = pkg->files[i]; reset_checker_context(&ctx, f, &untyped); -- cgit v1.2.3 From d5384c5aa4d823fbd527fb82e9eb5559b4266dfd Mon Sep 17 00:00:00 2001 From: gingerBill Date: Fri, 4 Feb 2022 22:45:13 +0000 Subject: Only check idents in the alias (of alias)+ problem --- src/check_decl.cpp | 2 +- src/check_expr.cpp | 4 ++-- src/checker.cpp | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) (limited to 'src/check_decl.cpp') diff --git a/src/check_decl.cpp b/src/check_decl.cpp index 2454feb33..63fc777c0 100644 --- a/src/check_decl.cpp +++ b/src/check_decl.cpp @@ -385,7 +385,7 @@ void check_const_decl(CheckerContext *ctx, Entity *e, Ast *type_expr, Ast *init, Operand operand = {}; if (init != nullptr) { - Entity *entity = check_entity_from_ident_or_selector(ctx, init); + Entity *entity = check_entity_from_ident_or_selector(ctx, init, false); if (entity != nullptr && entity->kind == Entity_TypeName) { // @TypeAliasingProblem // NOTE(bill, 2022-02-03): This is used to solve the problem caused by type aliases diff --git a/src/check_expr.cpp b/src/check_expr.cpp index e1c9bde84..d51444b4d 100644 --- a/src/check_expr.cpp +++ b/src/check_expr.cpp @@ -4082,11 +4082,11 @@ bool is_entity_declared_for_selector(Entity *entity, Scope *import_scope, bool * } // NOTE(bill, 2022-02-03): see `check_const_decl` for why it exists reasoning -Entity *check_entity_from_ident_or_selector(CheckerContext *c, Ast *node) { +Entity *check_entity_from_ident_or_selector(CheckerContext *c, Ast *node, bool ident_only) { if (node->kind == Ast_Ident) { String name = node->Ident.token.string; return scope_lookup(c->scope, name); - } else if (node->kind == Ast_SelectorExpr) { + } else if (!ident_only) if (node->kind == Ast_SelectorExpr) { ast_node(se, SelectorExpr, node); if (se->token.kind == Token_ArrowRight) { return nullptr; diff --git a/src/checker.cpp b/src/checker.cpp index c90f357dd..188d68502 100644 --- a/src/checker.cpp +++ b/src/checker.cpp @@ -3670,7 +3670,7 @@ bool correct_single_type_alias(CheckerContext *c, Entity *e) { DeclInfo *d = e->decl_info; if (d != nullptr && d->init_expr != nullptr) { Ast *init = d->init_expr; - Entity *alias_of = check_entity_from_ident_or_selector(c, init); + Entity *alias_of = check_entity_from_ident_or_selector(c, init, true); if (alias_of != nullptr && alias_of->kind == Entity_TypeName) { e->kind = Entity_TypeName; return true; -- cgit v1.2.3 From 1553137c2365c3980488a6455fd83f0fcb9e28ca Mon Sep 17 00:00:00 2001 From: gingerBill Date: Sat, 5 Feb 2022 00:04:02 +0000 Subject: Change behaviour of `A :: distinct Enum_Type` to be more intuitive --- src/check_decl.cpp | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 50 insertions(+), 1 deletion(-) (limited to 'src/check_decl.cpp') diff --git a/src/check_decl.cpp b/src/check_decl.cpp index 63fc777c0..f6dade812 100644 --- a/src/check_decl.cpp +++ b/src/check_decl.cpp @@ -238,6 +238,51 @@ isize total_attribute_count(DeclInfo *decl) { return attribute_count; } +Type *clone_enum_type(CheckerContext *ctx, Type *original_enum_type, Type *named_type) { + // NOTE(bill, 2022-02-05): Stupid edge case for `distinct` declarations + // + // X :: enum {A, B, C} + // Y :: distinct X + // + // To make Y be just like X, it will need to copy the elements of X and change their type + // so that they match Y rather than X. + GB_ASSERT(original_enum_type != nullptr); + GB_ASSERT(named_type != nullptr); + GB_ASSERT(original_enum_type->kind == Type_Enum); + GB_ASSERT(named_type->kind == Type_Named); + + Scope *parent = original_enum_type->Enum.scope->parent; + Scope *scope = create_scope(nullptr, parent); + + + Type *et = alloc_type_enum(); + et->Enum.base_type = original_enum_type->Enum.base_type; + et->Enum.min_value = original_enum_type->Enum.min_value; + et->Enum.max_value = original_enum_type->Enum.max_value; + et->Enum.min_value_index = original_enum_type->Enum.min_value_index; + et->Enum.max_value_index = original_enum_type->Enum.max_value_index; + et->Enum.scope = scope; + + auto fields = array_make(permanent_allocator(), original_enum_type->Enum.fields.count); + for_array(i, fields) { + Entity *old = original_enum_type->Enum.fields[i]; + + Entity *e = alloc_entity_constant(scope, old->token, named_type, old->Constant.value); + e->file = old->file; + e->identifier = clone_ast(old->identifier); + e->flags |= EntityFlag_Visited; + e->state = EntityState_Resolved; + e->Constant.flags = old->Constant.flags; + e->Constant.docs = old->Constant.docs; + e->Constant.comment = old->Constant.comment; + + fields[i] = e; + add_entity(ctx, scope, nullptr, e); + add_entity_use(ctx, e->identifier, e); + } + et->Enum.fields = fields; + return et; +} void check_type_decl(CheckerContext *ctx, Entity *e, Ast *init_expr, Type *def) { GB_ASSERT(e->type == nullptr); @@ -258,7 +303,11 @@ void check_type_decl(CheckerContext *ctx, Entity *e, Ast *init_expr, Type *def) Type *bt = check_type_expr(ctx, te, named); check_type_path_pop(ctx); - named->Named.base = base_type(bt); + Type *base = base_type(bt); + if (is_distinct && bt->kind == Type_Named && base->kind == Type_Enum) { + base = clone_enum_type(ctx, base, named); + } + named->Named.base = base; if (is_distinct && is_type_typeid(e->type)) { error(init_expr, "'distinct' cannot be applied to 'typeid'"); -- cgit v1.2.3