Files
Odin/src/check_stmt.cpp
gingerBill 54976c3249 v0.8.0
2018-02-09 18:03:06 +00:00

1948 lines
52 KiB
C++

void check_stmt_list(Checker *c, Array<AstNode *> stmts, u32 flags) {
if (stmts.count == 0) {
return;
}
if (flags&Stmt_CheckScopeDecls) {
check_scope_decls(c, stmts, cast(isize)(1.2*stmts.count));
}
bool ft_ok = (flags & Stmt_FallthroughAllowed) != 0;
flags &= ~Stmt_FallthroughAllowed;
isize max = stmts.count;
for (isize i = stmts.count-1; i >= 0; i--) {
if (stmts[i]->kind != AstNode_EmptyStmt) {
break;
}
max--;
}
for (isize i = 0; i < max; i++) {
AstNode *n = stmts[i];
if (n->kind == AstNode_EmptyStmt) {
continue;
}
u32 new_flags = flags;
if (ft_ok && i+1 == max) {
new_flags |= Stmt_FallthroughAllowed;
}
if (i+1 < max) {
switch (n->kind) {
case AstNode_ReturnStmt:
error(n, "Statements after this 'return' are never execu");
break;
case AstNode_BranchStmt:
error(n, "Statements after this '%.*s' are never executed", LIT(n->BranchStmt.token.string));
break;
}
}
check_stmt(c, n, new_flags);
}
}
bool check_is_terminating_list(Array<AstNode *> stmts) {
// Iterate backwards
for (isize n = stmts.count-1; n >= 0; n--) {
AstNode *stmt = stmts[n];
if (stmt->kind != AstNode_EmptyStmt) {
return check_is_terminating(stmt);
}
}
return false;
}
bool check_has_break_list(Array<AstNode *> stmts, bool implicit) {
for_array(i, stmts) {
AstNode *stmt = stmts[i];
if (check_has_break(stmt, implicit)) {
return true;
}
}
return false;
}
bool check_has_break(AstNode *stmt, bool implicit) {
switch (stmt->kind) {
case AstNode_BranchStmt:
if (stmt->BranchStmt.token.kind == Token_break) {
return implicit;
}
break;
case AstNode_BlockStmt:
return check_has_break_list(stmt->BlockStmt.stmts, implicit);
case AstNode_IfStmt:
if (check_has_break(stmt->IfStmt.body, implicit) ||
(stmt->IfStmt.else_stmt != nullptr && check_has_break(stmt->IfStmt.else_stmt, implicit))) {
return true;
}
break;
case AstNode_CaseClause:
return check_has_break_list(stmt->CaseClause.stmts, implicit);
}
return false;
}
// NOTE(bill): The last expression has to be a 'return' statement
// TODO(bill): This is a mild hack and should be probably handled properly
// TODO(bill): Warn/err against code after 'return' that it won't be executed
bool check_is_terminating(AstNode *node) {
switch (node->kind) {
case_ast_node(rs, ReturnStmt, node);
return true;
case_end;
case_ast_node(bs, BlockStmt, node);
return check_is_terminating_list(bs->stmts);
case_end;
case_ast_node(es, ExprStmt, node);
return check_is_terminating(es->expr);
case_end;
case_ast_node(is, IfStmt, node);
if (is->else_stmt != nullptr) {
if (check_is_terminating(is->body) &&
check_is_terminating(is->else_stmt)) {
return true;
}
}
case_end;
case_ast_node(ws, WhenStmt, node);
if (ws->else_stmt != nullptr) {
if (check_is_terminating(ws->body) &&
check_is_terminating(ws->else_stmt)) {
return true;
}
}
case_end;
case_ast_node(fs, ForStmt, node);
if (fs->cond == nullptr && !check_has_break(fs->body, true)) {
return check_is_terminating(fs->body);
}
case_end;
case_ast_node(rs, RangeStmt, node);
return false;
case_end;
case_ast_node(ss, SwitchStmt, node);
bool has_default = false;
for_array(i, ss->body->BlockStmt.stmts) {
AstNode *clause = ss->body->BlockStmt.stmts[i];
ast_node(cc, CaseClause, clause);
if (cc->list.count == 0) {
has_default = true;
}
if (!check_is_terminating_list(cc->stmts) ||
check_has_break_list(cc->stmts, true)) {
return false;
}
}
return has_default;
case_end;
case_ast_node(ss, TypeSwitchStmt, node);
bool has_default = false;
for_array(i, ss->body->BlockStmt.stmts) {
AstNode *clause = ss->body->BlockStmt.stmts[i];
ast_node(cc, CaseClause, clause);
if (cc->list.count == 0) {
has_default = true;
}
if (!check_is_terminating_list(cc->stmts) ||
check_has_break_list(cc->stmts, true)) {
return false;
}
}
return has_default;
case_end;
case_ast_node(pc, PushContext, node);
return check_is_terminating(pc->body);
case_end;
}
return false;
}
Type *check_assignment_variable(Checker *c, Operand *lhs, Operand *rhs) {
if (rhs->mode == Addressing_Invalid) {
return nullptr;
}
if (rhs->type == t_invalid &&
rhs->mode != Addressing_ProcGroup &&
rhs->mode != Addressing_Builtin) {
return nullptr;
}
AstNode *node = unparen_expr(lhs->expr);
// NOTE(bill): Ignore assignments to '_'
if (is_blank_ident(node)) {
add_entity_definition(&c->info, node, nullptr);
check_assignment(c, rhs, nullptr, str_lit("assignment to '_' identifier"));
if (rhs->mode == Addressing_Invalid) {
return nullptr;
}
return rhs->type;
}
Entity *e = nullptr;
bool used = false;
if (lhs->mode == Addressing_Invalid ||
(lhs->type == t_invalid &&
lhs->mode != Addressing_ProcGroup &&
lhs->mode != Addressing_Builtin)) {
return nullptr;
}
if (rhs->mode == Addressing_ProcGroup) {
Array<Entity *> procs = proc_group_entities(c, *rhs);
GB_ASSERT(procs.count > 0);
// NOTE(bill): These should be done
for_array(i, procs) {
Type *t = base_type(procs[i]->type);
if (t == t_invalid) {
continue;
}
Operand x = {};
x.mode = Addressing_Value;
x.type = t;
if (check_is_assignable_to(c, &x, lhs->type)) {
e = procs[i];
add_entity_use(c, rhs->expr, e);
break;
}
}
if (e != nullptr) {
// HACK TODO(bill): Should the entities be freed as it's technically a leak
rhs->mode = Addressing_Value;
rhs->type = e->type;
rhs->proc_group = nullptr;
}
} else {
if (node->kind == AstNode_Ident) {
ast_node(i, Ident, node);
e = scope_lookup_entity(c->context.scope, i->token.string);
if (e != nullptr && e->kind == Entity_Variable) {
used = (e->flags & EntityFlag_Used) != 0; // TODO(bill): Make backup just in case
}
}
}
if (e != nullptr && used) {
e->flags |= EntityFlag_Used;
}
Type *assignment_type = lhs->type;
switch (lhs->mode) {
case Addressing_Invalid:
return nullptr;
case Addressing_Variable: {
if (is_type_bit_field_value(lhs->type)) {
Type *lt = base_type(lhs->type);
i64 lhs_bits = lt->BitFieldValue.bits;
if (rhs->mode == Addressing_Constant) {
ExactValue v = exact_value_to_integer(rhs->value);
if (v.kind == ExactValue_Integer) {
i64 i = v.value_integer;
u64 u = *cast(u64 *)&i;
u64 umax = ~cast(u64)0ull;
if (lhs_bits < 64) {
umax = (1ull << cast(u64)lhs_bits) - 1ull;
}
i64 imax = 1ll << (cast(i64)lhs_bits-1ll);
bool ok = false;
ok = !(u < 0 || u > umax);
if (ok) {
return rhs->type;
}
}
} else if (is_type_integer(rhs->type)) {
// TODO(bill): Any other checks?
return rhs->type;
}
gbString lhs_expr = expr_to_string(lhs->expr);
gbString rhs_expr = expr_to_string(rhs->expr);
error(rhs->expr, "Cannot assign '%s' to bit field '%s'", rhs_expr, lhs_expr);
gb_string_free(rhs_expr);
gb_string_free(lhs_expr);
return nullptr;
}
break;
}
case Addressing_MapIndex: {
AstNode *ln = unparen_expr(lhs->expr);
if (ln->kind == AstNode_IndexExpr) {
AstNode *x = ln->IndexExpr.expr;
TypeAndValue tav = type_and_value_of_expr(&c->info, x);
GB_ASSERT(tav.mode != Addressing_Invalid);
if (tav.mode != Addressing_Variable) {
if (!is_type_pointer(tav.type)) {
gbString str = expr_to_string(lhs->expr);
error(lhs->expr, "Cannot assign to the value of a map '%s'", str);
gb_string_free(str);
return nullptr;
}
}
}
break;
}
default: {
if (lhs->expr->kind == AstNode_SelectorExpr) {
// NOTE(bill): Extra error checks
Operand op_c = {Addressing_Invalid};
ast_node(se, SelectorExpr, lhs->expr);
check_expr(c, &op_c, se->expr);
if (op_c.mode == Addressing_MapIndex) {
gbString str = expr_to_string(lhs->expr);
error(lhs->expr, "Cannot assign to struct field '%s' in map", str);
gb_string_free(str);
return nullptr;
}
}
gbString str = expr_to_string(lhs->expr);
if (lhs->mode == Addressing_Immutable) {
error(lhs->expr, "Cannot assign to an immutable: '%s'", str);
} else {
error(lhs->expr, "Cannot assign to '%s'", str);
}
gb_string_free(str);
break;
}
}
check_assignment(c, rhs, assignment_type, str_lit("assignment"));
if (rhs->mode == Addressing_Invalid) {
return nullptr;
}
return rhs->type;
}
enum SwitchKind {
Switch_Invalid,
Switch_Union,
Switch_Any,
};
SwitchKind check_valid_type_switch_type(Type *type) {
type = type_deref(type);
if (is_type_union(type)) {
return Switch_Union;
}
if (is_type_any(type)) {
return Switch_Any;
}
return Switch_Invalid;
}
void check_stmt_internal(Checker *c, AstNode *node, u32 flags);
void check_stmt(Checker *c, AstNode *node, u32 flags) {
u32 prev_stmt_state_flags = c->context.stmt_state_flags;
if (node->stmt_state_flags != 0) {
u32 in = node->stmt_state_flags;
u32 out = c->context.stmt_state_flags;
if (in & StmtStateFlag_no_bounds_check) {
out |= StmtStateFlag_no_bounds_check;
out &= ~StmtStateFlag_bounds_check;
} else {
// if (in & StmtStateFlag_bounds_check) {
out |= StmtStateFlag_bounds_check;
out &= ~StmtStateFlag_no_bounds_check;
}
c->context.stmt_state_flags = out;
}
check_stmt_internal(c, node, flags);
c->context.stmt_state_flags = prev_stmt_state_flags;
}
void check_when_stmt(Checker *c, AstNodeWhenStmt *ws, u32 flags) {
Operand operand = {Addressing_Invalid};
check_expr(c, &operand, ws->cond);
if (operand.mode != Addressing_Constant || !is_type_boolean(operand.type)) {
error(ws->cond, "Non-constant boolean 'when' condition");
return;
}
if (ws->body == nullptr || ws->body->kind != AstNode_BlockStmt) {
error(ws->cond, "Invalid body for 'when' statement");
return;
}
if (operand.value.kind == ExactValue_Bool &&
operand.value.value_bool) {
check_stmt_list(c, ws->body->BlockStmt.stmts, flags);
} else if (ws->else_stmt) {
switch (ws->else_stmt->kind) {
case AstNode_BlockStmt:
check_stmt_list(c, ws->else_stmt->BlockStmt.stmts, flags);
break;
case AstNode_WhenStmt:
check_when_stmt(c, &ws->else_stmt->WhenStmt, flags);
break;
default:
error(ws->else_stmt, "Invalid 'else' statement in 'when' statement");
break;
}
}
}
void check_label(Checker *c, AstNode *label) {
if (label == nullptr) {
return;
}
ast_node(l, Label, label);
if (l->name->kind != AstNode_Ident) {
error(l->name, "A label's name must be an identifier");
return;
}
String name = l->name->Ident.token.string;
if (is_blank_ident(name)) {
error(l->name, "A label's name cannot be a blank identifier");
return;
}
if (c->proc_stack.count == 0) {
error(l->name, "A label is only allowed within a procedure");
return;
}
GB_ASSERT(c->context.decl != nullptr);
bool ok = true;
for_array(i, c->context.decl->labels) {
BlockLabel bl = c->context.decl->labels[i];
if (bl.name == name) {
error(label, "Duplicate label with the name '%.*s'", LIT(name));
ok = false;
break;
}
}
Entity *e = make_entity_label(c->allocator, c->context.scope, l->name->Ident.token, t_invalid, label);
add_entity(c, c->context.scope, l->name, e);
e->parent_proc_decl = c->context.curr_proc_decl;
if (ok) {
BlockLabel bl = {name, label};
array_add(&c->context.decl->labels, bl);
}
}
// Returns 'true' for 'continue', 'false' for 'return'
bool check_using_stmt_entity(Checker *c, AstNodeUsingStmt *us, AstNode *expr, bool is_selector, Entity *e) {
if (e == nullptr) {
error(us->token, "'using' applied to an unknown entity");
return true;
}
add_entity_use(c, expr, e);
switch (e->kind) {
case Entity_TypeName: {
Type *t = base_type(e->type);
if (t->kind == Type_Enum) {
for (isize i = 0; i < t->Enum.field_count; i++) {
Entity *f = t->Enum.fields[i];
if (!is_entity_exported(f)) continue;
Entity *found = scope_insert_entity(c->context.scope, f);
if (found != nullptr) {
gbString expr_str = expr_to_string(expr);
error(us->token, "Namespace collision while 'using' '%s' of: %.*s", expr_str, LIT(found->token.string));
gb_string_free(expr_str);
return false;
}
f->using_parent = e;
}
} else {
error(us->token, "'using' can be only applied to enum type entities");
}
break;
}
case Entity_ImportName: {
Scope *scope = e->ImportName.scope;
for_array(i, scope->elements.entries) {
Entity *decl = scope->elements.entries[i].value;
if (!is_entity_exported(decl)) continue;
Entity *found = scope_insert_entity(c->context.scope, decl);
if (found != nullptr) {
gbString expr_str = expr_to_string(expr);
error(us->token,
"Namespace collision while 'using' '%s' of: %.*s\n"
"\tat %.*s(%td:%td)\n"
"\tat %.*s(%td:%td)",
expr_str, LIT(found->token.string),
LIT(found->token.pos.file), found->token.pos.line, found->token.pos.column,
LIT(decl->token.pos.file), decl->token.pos.line, decl->token.pos.column
);
gb_string_free(expr_str);
return false;
}
}
break;
}
case Entity_Variable: {
Type *t = base_type(type_deref(e->type));
if (t->kind == Type_Struct) {
// TODO(bill): Make it work for unions too
Scope *found = scope_of_node(&c->info, t->Struct.node);
for_array(i, found->elements.entries) {
Entity *f = found->elements.entries[i].value;
if (f->kind == Entity_Variable) {
Entity *uvar = make_entity_using_variable(c->allocator, e, f->token, f->type);
uvar->using_expr = expr;
Entity *prev = scope_insert_entity(c->context.scope, uvar);
if (prev != nullptr) {
gbString expr_str = expr_to_string(expr);
error(us->token, "Namespace collision while using '%s' of: '%.*s'", expr_str, LIT(prev->token.string));
gb_string_free(expr_str);
return false;
}
}
}
} else {
error(us->token, "'using' can only be applied to variables of type 'struct'");
return false;
}
break;
}
case Entity_Constant:
error(us->token, "'using' cannot be applied to a constant");
break;
case Entity_Procedure:
case Entity_ProcGroup:
case Entity_Builtin:
error(us->token, "'using' cannot be applied to a procedure");
break;
case Entity_Nil:
error(us->token, "'using' cannot be applied to 'nil'");
break;
case Entity_Label:
error(us->token, "'using' cannot be applied to a label");
break;
case Entity_Invalid:
error(us->token, "'using' cannot be applied to an invalid entity");
break;
default:
GB_PANIC("TODO(bill): 'using' other expressions?");
}
return true;
}
void check_switch_stmt(Checker *c, AstNode *node, u32 mod_flags) {
ast_node(ss, SwitchStmt, node);
Operand x = {};
mod_flags |= Stmt_BreakAllowed | Stmt_FallthroughAllowed;
check_open_scope(c, node);
defer (check_close_scope(c));
check_label(c, ss->label); // TODO(bill): What should the label's "scope" be?
if (ss->init != nullptr) {
check_stmt(c, ss->init, 0);
}
if (ss->tag != nullptr) {
check_expr(c, &x, ss->tag);
check_assignment(c, &x, nullptr, str_lit("switch expression"));
} else {
x.mode = Addressing_Constant;
x.type = t_bool;
x.value = exact_value_bool(true);
Token token = {};
token.pos = ast_node_token(ss->body).pos;
token.string = str_lit("true");
x.expr = ast_ident(c->curr_ast_file, token);
}
// NOTE(bill): Check for multiple defaults
AstNode *first_default = nullptr;
ast_node(bs, BlockStmt, ss->body);
for_array(i, bs->stmts) {
AstNode *stmt = bs->stmts[i];
AstNode *default_stmt = nullptr;
if (stmt->kind == AstNode_CaseClause) {
ast_node(cc, CaseClause, stmt);
if (cc->list.count == 0) {
default_stmt = stmt;
}
} else {
error(stmt, "Invalid AST - expected case clause");
}
if (default_stmt != nullptr) {
if (first_default != nullptr) {
TokenPos pos = ast_node_token(first_default).pos;
error(stmt,
"multiple default clauses\n"
"\tfirst at %.*s(%td:%td)",
LIT(pos.file), pos.line, pos.column);
} else {
first_default = default_stmt;
}
}
}
struct TypeAndToken {
Type *type;
Token token;
};
Map<TypeAndToken> seen = {}; // NOTE(bill): Multimap
map_init(&seen, heap_allocator());
defer (map_destroy(&seen));
for_array(stmt_index, bs->stmts) {
AstNode *stmt = bs->stmts[stmt_index];
if (stmt->kind != AstNode_CaseClause) {
// NOTE(bill): error handled by above multiple default checker
continue;
}
ast_node(cc, CaseClause, stmt);
for_array(j, cc->list) {
AstNode *expr = unparen_expr(cc->list[j]);
if (is_ast_node_a_range(expr)) {
ast_node(ie, BinaryExpr, expr);
Operand lhs = {};
Operand rhs = {};
check_expr(c, &lhs, ie->left);
if (x.mode == Addressing_Invalid) {
continue;
}
if (lhs.mode == Addressing_Invalid) {
continue;
}
check_expr(c, &rhs, ie->right);
if (rhs.mode == Addressing_Invalid) {
continue;
}
if (!is_type_ordered(x.type)) {
gbString str = type_to_string(x.type);
error(expr, "Unordered type '%s', is invalid for an interval expression", str);
gb_string_free(str);
continue;
}
TokenKind op = Token_Invalid;
Operand a = lhs;
Operand b = rhs;
check_comparison(c, &a, &x, Token_LtEq);
if (a.mode == Addressing_Invalid) {
continue;
}
switch (ie->op.kind) {
case Token_Ellipsis: op = Token_GtEq; break;
case Token_HalfClosed: op = Token_Gt; break;
default: error(ie->op, "Invalid interval operator"); continue;
}
check_comparison(c, &b, &x, op);
if (b.mode == Addressing_Invalid) {
continue;
}
switch (ie->op.kind) {
case Token_Ellipsis: op = Token_LtEq; break;
case Token_HalfClosed: op = Token_Lt; break;
default: error(ie->op, "Invalid interval operator"); continue;
}
Operand a1 = lhs;
Operand b1 = rhs;
check_comparison(c, &a1, &b1, op);
} else {
Operand y = {};
check_expr(c, &y, expr);
if (x.mode == Addressing_Invalid ||
y.mode == Addressing_Invalid) {
continue;
}
convert_to_typed(c, &y, x.type);
if (y.mode == Addressing_Invalid) {
continue;
}
// NOTE(bill): the ordering here matters
Operand z = y;
check_comparison(c, &z, &x, Token_CmpEq);
if (z.mode == Addressing_Invalid) {
continue;
}
if (y.mode != Addressing_Constant) {
continue;
}
if (y.value.kind != ExactValue_Invalid) {
HashKey key = hash_exact_value(y.value);
TypeAndToken *found = map_get(&seen, key);
if (found != nullptr) {
gbTempArenaMemory tmp = gb_temp_arena_memory_begin(&c->tmp_arena);
defer (gb_temp_arena_memory_end(tmp));
isize count = multi_map_count(&seen, key);
TypeAndToken *taps = gb_alloc_array(c->tmp_allocator, TypeAndToken, count);
multi_map_get_all(&seen, key, taps);
bool continue_outer = false;
for (isize i = 0; i < count; i++) {
TypeAndToken tap = taps[i];
if (are_types_identical(y.type, tap.type)) {
TokenPos pos = tap.token.pos;
gbString expr_str = expr_to_string(y.expr);
error(y.expr,
"Duplicate case '%s'\n"
"\tprevious case at %.*s(%td:%td)",
expr_str,
LIT(pos.file), pos.line, pos.column);
gb_string_free(expr_str);
continue_outer = true;
break;
}
}
if (continue_outer) {
continue;
}
}
TypeAndToken tap = {y.type, ast_node_token(y.expr)};
multi_map_insert(&seen, key, tap);
}
}
}
check_open_scope(c, stmt);
check_stmt_list(c, cc->stmts, mod_flags);
check_close_scope(c);
}
}
void check_type_switch_stmt(Checker *c, AstNode *node, u32 mod_flags) {
ast_node(ss, TypeSwitchStmt, node);
Operand x = {};
mod_flags |= Stmt_BreakAllowed;
check_open_scope(c, node);
check_label(c, ss->label); // TODO(bill): What should the label's "scope" be?
SwitchKind switch_kind = Switch_Invalid;
if (ss->tag->kind != AstNode_AssignStmt) {
error(ss->tag, "Expected an 'in' assignment for this type switch statement");
return;
}
ast_node(as, AssignStmt, ss->tag);
Token as_token = ast_node_token(ss->tag);
if (as->lhs.count != 1) {
syntax_error(as_token, "Expected 1 name before 'in'");
return;
}
if (as->rhs.count != 1) {
syntax_error(as_token, "Expected 1 expression after 'in'");
return;
}
AstNode *lhs = as->lhs[0];
AstNode *rhs = as->rhs[0];
check_expr(c, &x, rhs);
check_assignment(c, &x, nullptr, str_lit("type switch expression"));
switch_kind = check_valid_type_switch_type(x.type);
if (check_valid_type_switch_type(x.type) == Switch_Invalid) {
gbString str = type_to_string(x.type);
error(x.expr, "Invalid type for this type switch expression, got '%s'", str);
gb_string_free(str);
return;
}
bool is_ptr = is_type_pointer(x.type);
// NOTE(bill): Check for multiple defaults
AstNode *first_default = nullptr;
ast_node(bs, BlockStmt, ss->body);
for_array(i, bs->stmts) {
AstNode *stmt = bs->stmts[i];
AstNode *default_stmt = nullptr;
if (stmt->kind == AstNode_CaseClause) {
ast_node(cc, CaseClause, stmt);
if (cc->list.count == 0) {
default_stmt = stmt;
}
} else {
error(stmt, "Invalid AST - expected case clause");
}
if (default_stmt != nullptr) {
if (first_default != nullptr) {
TokenPos pos = ast_node_token(first_default).pos;
error(stmt,
"Multiple 'default' clauses\n"
"\tfirst at %.*s(%td:%td)", LIT(pos.file), pos.line, pos.column);
} else {
first_default = default_stmt;
}
}
}
if (lhs->kind != AstNode_Ident) {
error(rhs, "Expected an identifier, got '%.*s'", LIT(ast_node_strings[rhs->kind]));
return;
}
Map<bool> seen = {}; // Multimap, Key: Type *
map_init(&seen, heap_allocator());
for_array(i, bs->stmts) {
AstNode *stmt = bs->stmts[i];
if (stmt->kind != AstNode_CaseClause) {
// NOTE(bill): error handled by above multiple default checker
continue;
}
ast_node(cc, CaseClause, stmt);
// TODO(bill): Make robust
Type *bt = base_type(type_deref(x.type));
Type *case_type = nullptr;
for_array(type_index, cc->list) {
AstNode *type_expr = cc->list[type_index];
if (type_expr != nullptr) { // Otherwise it's a default expression
Operand y = {};
check_expr_or_type(c, &y, type_expr);
if (switch_kind == Switch_Union) {
GB_ASSERT(is_type_union(bt));
bool tag_type_found = false;
for_array(i, bt->Union.variants) {
Type *vt = bt->Union.variants[i];
if (are_types_identical(vt, y.type)) {
tag_type_found = true;
break;
}
}
if (!tag_type_found) {
gbString type_str = type_to_string(y.type);
error(y.expr, "Unknown tag type, got '%s'", type_str);
gb_string_free(type_str);
continue;
}
case_type = y.type;
} else if (switch_kind == Switch_Any) {
case_type = y.type;
} else {
GB_PANIC("Unknown type to type switch statement");
}
HashKey key = hash_type(y.type);
bool *found = map_get(&seen, key);
if (found) {
TokenPos pos = cc->token.pos;
gbString expr_str = expr_to_string(y.expr);
error(y.expr,
"Duplicate type case '%s'\n"
"\tprevious type case at %.*s(%td:%td)",
expr_str,
LIT(pos.file), pos.line, pos.column);
gb_string_free(expr_str);
break;
}
map_set(&seen, key, cast(bool)true);
}
}
if (is_ptr &&
!is_type_any(type_deref(x.type)) &&
cc->list.count == 1 &&
case_type != nullptr) {
case_type = make_type_pointer(c->allocator, case_type);
}
if (cc->list.count > 1) {
case_type = nullptr;
}
if (case_type == nullptr) {
case_type = x.type;
}
add_type_info_type(c, case_type);
check_open_scope(c, stmt);
{
Entity *tag_var = make_entity_variable(c->allocator, c->context.scope, lhs->Ident.token, case_type, false);
tag_var->flags |= EntityFlag_Used;
tag_var->flags |= EntityFlag_Value;
add_entity(c, c->context.scope, lhs, tag_var);
add_entity_use(c, lhs, tag_var);
add_implicit_entity(c, stmt, tag_var);
}
check_stmt_list(c, cc->stmts, mod_flags);
check_close_scope(c);
}
map_destroy(&seen);
check_close_scope(c);
}
void check_stmt_internal(Checker *c, AstNode *node, u32 flags) {
u32 mod_flags = flags & (~Stmt_FallthroughAllowed);
switch (node->kind) {
case_ast_node(_, EmptyStmt, node); case_end;
case_ast_node(_, BadStmt, node); case_end;
case_ast_node(_, BadDecl, node); case_end;
case_ast_node(es, ExprStmt, node)
Operand operand = {Addressing_Invalid};
ExprKind kind = check_expr_base(c, &operand, es->expr, nullptr);
switch (operand.mode) {
case Addressing_Type: {
gbString str = type_to_string(operand.type);
error(node, "'%s' is not an expression", str);
gb_string_free(str);
break;
}
case Addressing_NoValue:
return;
default: {
if (kind == Expr_Stmt) {
return;
}
if (operand.expr->kind == AstNode_CallExpr) {
AstNodeCallExpr *ce = &operand.expr->CallExpr;
Type *t = type_of_expr(&c->info, ce->proc);
if (is_type_proc(t)) {
if (t->Proc.require_results) {
gbString expr_str = expr_to_string(ce->proc);
error(node, "'%s' requires that its results must be handled", expr_str);
gb_string_free(expr_str);
}
}
return;
}
gbString expr_str = expr_to_string(operand.expr);
error(node, "Expression is not used: '%s'", expr_str);
gb_string_free(expr_str);
break;
}
}
case_end;
case_ast_node(ts, TagStmt, node);
// TODO(bill): Tag Statements
error(node, "Tag statements are not supported yet");
check_stmt(c, ts->stmt, flags);
case_end;
#if 0
case_ast_node(s, IncDecStmt, node);
TokenKind op = s->op.kind;
switch (op) {
case Token_Inc: op = Token_Add; break;
case Token_Dec: op = Token_Sub; break;
default:
error(node, "Invalid inc/dec operation");
return;
}
Operand x = {};
check_expr(c, &x, s->expr);
if (x.mode == Addressing_Invalid) {
return;
}
if (!is_type_integer(x.type) && !is_type_float(x.type)) {
gbString e = expr_to_string(s->expr);
gbString t = type_to_string(x.type);
error(node, "%s%.*s used on non-numeric type %s", e, LIT(s->op.string), t);
gb_string_free(t);
gb_string_free(e);
return;
}
AstNode *left = s->expr;
AstNode *right = gb_alloc_item(c->allocator, AstNode);
right->kind = AstNode_BasicLit;
right->BasicLit.pos = s->op.pos;
right->BasicLit.kind = Token_Integer;
right->BasicLit.string = str_lit("1");
AstNode *be = gb_alloc_item(c->allocator, AstNode);
be->kind = AstNode_BinaryExpr;
be->BinaryExpr.op = s->op;
be->BinaryExpr.op.kind = op;
be->BinaryExpr.left = left;
be->BinaryExpr.right = right;
check_binary_expr(c, &x, be);
if (x.mode == Addressing_Invalid) {
return;
}
check_assignment_variable(c, &x, left);
case_end;
#endif
case_ast_node(as, AssignStmt, node);
switch (as->op.kind) {
case Token_Eq: {
// a, b, c = 1, 2, 3; // Multisided
isize lhs_count = as->lhs.count;
if (lhs_count == 0) {
error(as->op, "Missing lhs in assignment statement");
return;
}
gbTempArenaMemory tmp = gb_temp_arena_memory_begin(&c->tmp_arena);
defer (gb_temp_arena_memory_end(tmp));
// NOTE(bill): If there is a bad syntax error, rhs > lhs which would mean there would need to be
// an extra allocation
Array<Operand> lhs_operands = {};
Array<Operand> rhs_operands = {};
array_init_count(&lhs_operands, c->tmp_allocator, lhs_count);
array_init(&rhs_operands, c->tmp_allocator, 2 * lhs_count);
for_array(i, as->lhs) {
if (is_blank_ident(as->lhs[i])) {
Operand *o = &lhs_operands[i];
o->expr = as->lhs[i];
o->mode = Addressing_Value;
} else {
check_expr(c, &lhs_operands[i], as->lhs[i]);
}
}
check_unpack_arguments(c, nullptr, lhs_operands.count, &rhs_operands, as->rhs, true);
isize rhs_count = rhs_operands.count;
for_array(i, rhs_operands) {
if (rhs_operands[i].mode == Addressing_Invalid) {
rhs_count--;
}
}
isize max = gb_min(lhs_count, rhs_count);
for (isize i = 0; i < max; i++) {
check_assignment_variable(c, &lhs_operands[i], &rhs_operands[i]);
}
if (lhs_count != rhs_count) {
error(as->lhs[0], "Assignment count mismatch '%td' = '%td'", lhs_count, rhs_count);
}
break;
}
default: {
// a += 1; // Single-sided
Token op = as->op;
if (as->lhs.count != 1 || as->rhs.count != 1) {
error(op, "Assignment operation '%.*s' requires single-valued expressions", LIT(op.string));
return;
}
if (!gb_is_between(op.kind, Token__AssignOpBegin+1, Token__AssignOpEnd-1)) {
error(op, "Unknown Assignment operation '%.*s'", LIT(op.string));
return;
}
Operand lhs = {Addressing_Invalid};
Operand rhs = {Addressing_Invalid};
AstNode binary_expr = {AstNode_BinaryExpr};
ast_node(be, BinaryExpr, &binary_expr);
be->op = op;
be->op.kind = cast(TokenKind)(cast(i32)be->op.kind - (Token_AddEq - Token_Add));
// NOTE(bill): Only use the first one will be used
be->left = as->lhs[0];
be->right = as->rhs[0];
check_expr(c, &lhs, as->lhs[0]);
check_binary_expr(c, &rhs, &binary_expr);
if (rhs.mode == Addressing_Invalid) {
return;
}
// NOTE(bill): Only use the first one will be used
check_assignment_variable(c, &lhs, &rhs);
break;
}
}
case_end;
case_ast_node(bs, BlockStmt, node);
check_open_scope(c, node);
check_stmt_list(c, bs->stmts, flags);
check_close_scope(c);
case_end;
case_ast_node(is, IfStmt, node);
check_open_scope(c, node);
if (is->init != nullptr) {
check_stmt(c, is->init, 0);
}
Operand operand = {Addressing_Invalid};
check_expr(c, &operand, is->cond);
if (operand.mode != Addressing_Invalid && !is_type_boolean(operand.type)) {
error(is->cond, "Non-boolean condition in 'if' statement");
}
check_stmt(c, is->body, mod_flags);
if (is->else_stmt != nullptr) {
switch (is->else_stmt->kind) {
case AstNode_IfStmt:
case AstNode_BlockStmt:
check_stmt(c, is->else_stmt, mod_flags);
break;
default:
error(is->else_stmt, "Invalid 'else' statement in 'if' statement");
break;
}
}
check_close_scope(c);
case_end;
case_ast_node(ws, WhenStmt, node);
check_when_stmt(c, ws, flags);
case_end;
case_ast_node(rs, ReturnStmt, node);
GB_ASSERT(c->proc_stack.count > 0);
if (c->context.in_defer) {
error(rs->token, "You cannot 'return' within a defer statement");
break;
}
// bool first_is_field_value = false;
// if (rs->results.count > 0) {
// bool fail = false;
// first_is_field_value = (rs->results[0]->kind == AstNode_FieldValue);
// for_array(i, rs->results) {
// AstNode *arg = rs->results[i];
// bool mix = false;
// if (first_is_field_value) {
// mix = arg->kind != AstNode_FieldValue;
// } else {
// mix = arg->kind == AstNode_FieldValue;
// }
// if (mix) {
// error(arg, "Mixture of 'field = value' and value elements in a procedure all is not allowed");
// fail = true;
// }
// }
// if (fail) {
// return;
// }
// }
Type *proc_type = c->proc_stack[c->proc_stack.count-1];
TypeProc *pt = &proc_type->Proc;
isize result_count = 0;
bool has_named_results = pt->has_named_results;
if (pt->results) {
result_count = proc_type->Proc.results->Tuple.variables.count;
}
// isize result_count_excluding_defaults = result_count;
// for (isize i = result_count-1; i >= 0; i--) {
// Entity *e = pt->results->Tuple.variables[i];
// if (e->kind == Entity_TypeName) {
// break;
// }
// GB_ASSERT(e->kind == Entity_Variable);
// if (e->Variable.default_value.kind != ExactValue_Invalid ||
// e->Variable.default_is_nil) {
// result_count_excluding_defaults--;
// continue;
// }
// break;
// }
Array<Operand> operands = {};
defer (array_free(&operands));
// if (first_is_field_value) {
// array_init_count(&operands, heap_allocator(), rs->results.count);
// for_array(i, rs->results) {
// AstNode *arg = rs->results[i];
// ast_node(fv, FieldValue, arg);
// check_expr(c, &operands[i], fv->value);
// }
// } else {
array_init(&operands, heap_allocator(), 2*rs->results.count);
check_unpack_arguments(c, nullptr, -1, &operands, rs->results, false);
// }
if (result_count == 0 && rs->results.count > 0) {
error(rs->results[0], "No return values expected");
} else if (has_named_results && operands.count == 0) {
// Okay
} else if (operands.count != result_count) {
error(node, "Expected %td return values, got %td", result_count, operands.count);
} else {
isize max_count = rs->results.count;
for (isize i = 0; i < max_count; i++) {
Entity *e = pt->results->Tuple.variables[i];
check_assignment(c, &operands[i], e->type, str_lit("return statement"));
}
}
case_end;
case_ast_node(fs, ForStmt, node);
u32 new_flags = mod_flags | Stmt_BreakAllowed | Stmt_ContinueAllowed;
check_open_scope(c, node);
check_label(c, fs->label); // TODO(bill): What should the label's "scope" be?
if (fs->init != nullptr) {
check_stmt(c, fs->init, 0);
}
if (fs->cond != nullptr) {
Operand o = {Addressing_Invalid};
check_expr(c, &o, fs->cond);
if (o.mode != Addressing_Invalid && !is_type_boolean(o.type)) {
error(fs->cond, "Non-boolean condition in 'for' statement");
}
}
if (fs->post != nullptr) {
check_stmt(c, fs->post, 0);
if (fs->post->kind != AstNode_AssignStmt &&
fs->post->kind != AstNode_IncDecStmt) {
error(fs->post, "'for' statement post statement must be a simple statement");
}
}
check_stmt(c, fs->body, new_flags);
check_close_scope(c);
case_end;
case_ast_node(rs, RangeStmt, node);
u32 new_flags = mod_flags | Stmt_BreakAllowed | Stmt_ContinueAllowed;
check_open_scope(c, node);
check_label(c, rs->label);
Type *val0 = nullptr;
Type *val1 = nullptr;
Entity *entities[2] = {};
isize entity_count = 0;
bool is_map = false;
AstNode *expr = unparen_expr(rs->expr);
if (is_ast_node_a_range(expr)) {
ast_node(ie, BinaryExpr, expr);
Operand x = {Addressing_Invalid};
Operand y = {Addressing_Invalid};
check_expr(c, &x, ie->left);
if (x.mode == Addressing_Invalid) {
goto skip_expr;
}
check_expr(c, &y, ie->right);
if (y.mode == Addressing_Invalid) {
goto skip_expr;
}
convert_to_typed(c, &x, y.type);
if (x.mode == Addressing_Invalid) {
goto skip_expr;
}
convert_to_typed(c, &y, x.type);
if (y.mode == Addressing_Invalid) {
goto skip_expr;
}
convert_to_typed(c, &x, default_type(y.type));
if (x.mode == Addressing_Invalid) {
goto skip_expr;
}
convert_to_typed(c, &y, default_type(x.type));
if (y.mode == Addressing_Invalid) {
goto skip_expr;
}
if (!are_types_identical(x.type, y.type)) {
if (x.type != t_invalid &&
y.type != t_invalid) {
gbString xt = type_to_string(x.type);
gbString yt = type_to_string(y.type);
gbString expr_str = expr_to_string(x.expr);
error(ie->op, "Mismatched types in interval expression '%s' : '%s' vs '%s'", expr_str, xt, yt);
gb_string_free(expr_str);
gb_string_free(yt);
gb_string_free(xt);
}
goto skip_expr;
}
Type *type = x.type;
if (!is_type_integer(type) && !is_type_float(type) && !is_type_pointer(type)) {
error(ie->op, "Only numerical and pointer types are allowed within interval expressions");
goto skip_expr;
}
if (x.mode == Addressing_Constant &&
y.mode == Addressing_Constant) {
ExactValue a = x.value;
ExactValue b = y.value;
GB_ASSERT(are_types_identical(x.type, y.type));
TokenKind op = Token_Lt;
switch (ie->op.kind) {
case Token_Ellipsis: op = Token_LtEq; break;
case Token_HalfClosed: op = Token_Lt; break;
default: error(ie->op, "Invalid range operator"); break;
}
bool ok = compare_exact_values(op, a, b);
if (!ok) {
// TODO(bill): Better error message
error(ie->op, "Invalid interval range");
goto skip_expr;
}
}
if (x.mode != Addressing_Constant) {
x.value = empty_exact_value;
}
if (y.mode != Addressing_Constant) {
y.value = empty_exact_value;
}
add_type_and_value(&c->info, ie->left, x.mode, x.type, x.value);
add_type_and_value(&c->info, ie->right, y.mode, y.type, y.value);
val0 = type;
val1 = t_int;
} else {
Operand operand = {Addressing_Invalid};
check_expr_or_type(c, &operand, rs->expr);
if (operand.mode == Addressing_Type) {
if (!is_type_enum(operand.type)) {
gbString t = type_to_string(operand.type);
error(operand.expr, "Cannot iterate over the type '%s'", t);
gb_string_free(t);
goto skip_expr;
} else {
val0 = operand.type;
val1 = t_int;
add_type_info_type(c, operand.type);
goto skip_expr;
}
} else if (operand.mode != Addressing_Invalid) {
bool is_ptr = is_type_pointer(operand.type);
Type *t = base_type(type_deref(operand.type));
switch (t->kind) {
case Type_Basic:
if (is_type_string(t)) {
val0 = t_rune;
val1 = t_int;
}
break;
case Type_Array:
val0 = t->Array.elem;
val1 = t_int;
break;
case Type_DynamicArray:
val0 = t->DynamicArray.elem;
val1 = t_int;
break;
case Type_Slice:
val0 = t->Slice.elem;
val1 = t_int;
break;
case Type_Map:
is_map = true;
val0 = t->Map.key;
val1 = t->Map.value;
break;
}
}
if (val0 == nullptr) {
gbString s = expr_to_string(operand.expr);
gbString t = type_to_string(operand.type);
error(operand.expr, "Cannot iterate over '%s' of type '%s'", s, t);
gb_string_free(t);
gb_string_free(s);
}
}
skip_expr:; // NOTE(zhiayang): again, declaring a variable immediately after a label... weird.
AstNode *lhs[2] = {rs->val0, rs->val1};
Type * rhs[2] = {val0, val1};
for (isize i = 0; i < 2; i++) {
if (lhs[i] == nullptr) {
continue;
}
AstNode *name = lhs[i];
Type * type = rhs[i];
Entity *entity = nullptr;
if (name->kind == AstNode_Ident) {
Token token = name->Ident.token;
String str = token.string;
Entity *found = nullptr;
if (!is_blank_ident(str)) {
found = current_scope_lookup_entity(c->context.scope, str);
}
if (found == nullptr) {
bool is_immutable = true;
entity = make_entity_variable(c->allocator, c->context.scope, token, type, is_immutable);
add_entity_definition(&c->info, name, entity);
} else {
TokenPos pos = found->token.pos;
error(token,
"Redeclaration of '%.*s' in this scope\n"
"\tat %.*s(%td:%td)",
LIT(str), LIT(pos.file), pos.line, pos.column);
entity = found;
}
} else {
error(name, "A variable declaration must be an identifier");
}
if (entity == nullptr) {
entity = make_entity_dummy_variable(c->allocator, c->global_scope, ast_node_token(name));
}
entities[entity_count++] = entity;
if (type == nullptr) {
entity->type = t_invalid;
entity->flags |= EntityFlag_Used;
}
}
for (isize i = 0; i < entity_count; i++) {
add_entity(c, c->context.scope, entities[i]->identifier, entities[i]);
}
check_stmt(c, rs->body, new_flags);
check_close_scope(c);
case_end;
case_ast_node(ss, SwitchStmt, node);
check_switch_stmt(c, node, mod_flags);
case_end;
case_ast_node(ss, TypeSwitchStmt, node);
check_type_switch_stmt(c, node, mod_flags);
case_end;
case_ast_node(ds, DeferStmt, node);
if (is_ast_node_decl(ds->stmt)) {
error(ds->token, "You cannot defer a declaration");
} else {
bool out_in_defer = c->context.in_defer;
c->context.in_defer = true;
check_stmt(c, ds->stmt, 0);
c->context.in_defer = out_in_defer;
}
case_end;
case_ast_node(bs, BranchStmt, node);
Token token = bs->token;
switch (token.kind) {
case Token_break:
if ((flags & Stmt_BreakAllowed) == 0) {
error(token, "'break' only allowed in loops or 'switch' statements");
}
break;
case Token_continue:
if ((flags & Stmt_ContinueAllowed) == 0) {
error(token, "'continue' only allowed in loops");
}
break;
case Token_fallthrough:
if ((flags & Stmt_FallthroughAllowed) == 0) {
error(token, "'fallthrough' statement in illegal position, expected at the end of a 'case' block");
}
break;
default:
error(token, "Invalid AST: Branch Statement '%.*s'", LIT(token.string));
break;
}
if (bs->label != nullptr) {
if (bs->label->kind != AstNode_Ident) {
error(bs->label, "A branch statement's label name must be an identifier");
return;
}
AstNode *ident = bs->label;
String name = ident->Ident.token.string;
Operand o = {};
Entity *e = check_ident(c, &o, ident, nullptr, nullptr, false);
if (e == nullptr) {
error(ident, "Undeclared label name: %.*s", LIT(name));
return;
}
add_entity_use(c, ident, e);
if (e->kind != Entity_Label) {
error(ident, "'%.*s' is not a label", LIT(name));
return;
}
}
case_end;
case_ast_node(us, UsingStmt, node);
if (us->list.count == 0) {
error(us->token, "Empty 'using' list");
return;
}
for_array(i, us->list) {
AstNode *expr = unparen_expr(us->list[0]);
Entity *e = nullptr;
bool is_selector = false;
Operand o = {};
switch (expr->kind) {
case AstNode_Ident:
e = check_ident(c, &o, expr, nullptr, nullptr, true);
break;
case AstNode_SelectorExpr:
e = check_selector(c, &o, expr, nullptr);
is_selector = true;
break;
case AstNode_Implicit:
error(us->token, "'using' applied to an implicit value");
continue;
default:
error(us->token, "'using' can only be applied to an entity, got %.*s", LIT(ast_node_strings[expr->kind]));
continue;
}
if (!check_using_stmt_entity(c, us, expr, is_selector, e)) {
return;
}
}
case_end;
case_ast_node(uis, UsingInStmt, node);
if (uis->list.count == 0) {
error(node, "Empty 'using' list");
return;
}
AstNode *expr = uis->expr;
Entity *e = nullptr;
Operand o = {};
if (expr->kind == AstNode_Ident) {
e = check_ident(c, &o, expr, nullptr, nullptr, true);
} else if (expr->kind == AstNode_SelectorExpr) {
e = check_selector(c, &o, expr, nullptr);
}
if (e == nullptr) {
error(expr, "'using' applied to an unknown entity");
return;
}
add_entity_use(c, expr, e);
switch (e->kind) {
case Entity_TypeName: {
Type *t = base_type(e->type);
if (t->kind == Type_Enum) {
GB_ASSERT(t->Enum.scope != nullptr);
for_array(list_index, uis->list) {
AstNode *node = uis->list[list_index];
ast_node(ident, Ident, node);
String name = ident->token.string;
Entity *f = scope_lookup_entity(t->Enum.scope, name);
if (f == nullptr || !is_entity_exported(f)) {
if (is_blank_ident(name)) {
error(node, "'_' cannot be used as a value");
} else {
error(node, "Undeclared name in this enumeration: '%.*s'", LIT(name));
}
continue;
}
add_entity_use(c, node, f);
add_entity(c, c->context.scope, node, f);
}
} else {
error(node, "'using' can be only applied to enum type entities");
}
break;
}
case Entity_ImportName: {
Scope *scope = e->ImportName.scope;
for_array(list_index, uis->list) {
AstNode *node = uis->list[list_index];
ast_node(ident, Ident, node);
String name = ident->token.string;
Entity *f = scope_lookup_entity(scope, name);
if (f == nullptr) {
if (is_blank_ident(name)) {
error(node, "'_' cannot be used as a value");
} else {
error(node, "Undeclared name in this import name: '%.*s'", LIT(name));
}
continue;
}
bool implicit_is_found = ptr_set_exists(&scope->implicit, f);
if (is_entity_exported(f) && !implicit_is_found) {
add_entity_use(c, node, f);
add_entity(c, c->context.scope, node, f);
} else {
error(node, "'%.*s' is exported from '%.*s'", LIT(f->token.string), LIT(e->token.string));
continue;
}
}
break;
}
case Entity_Variable: {
Type *t = base_type(type_deref(e->type));
if (t->kind == Type_Struct) {
// TODO(bill): Make it work for unions too
Scope *found = scope_of_node(&c->info, t->Struct.node);
for_array(list_index, uis->list) {
AstNode *node = uis->list[list_index];
ast_node(ident, Ident, node);
String name = ident->token.string;
Entity *f = scope_lookup_entity(found, name);
if (f == nullptr || f->kind != Entity_Variable) {
if (is_blank_ident(name)) {
error(node, "'_' cannot be used as a value");
} else {
error(node, "Undeclared name in this variable: '%.*s'", LIT(name));
}
continue;
}
Entity *uvar = make_entity_using_variable(c->allocator, e, f->token, f->type);
uvar->using_expr = expr;
Entity *prev = scope_insert_entity(c->context.scope, uvar);
if (prev != nullptr) {
gbString expr_str = expr_to_string(expr);
error(node, "Namespace collision while using '%s' of: '%.*s'", expr_str, LIT(prev->token.string));
gb_string_free(expr_str);
continue;
}
}
} else {
error(node, "'using' can only be applied to variables of type `struct`");
return;
}
break;
}
case Entity_Constant:
error(node, "'using' cannot be applied to a constant");
break;
case Entity_Procedure:
case Entity_ProcGroup:
case Entity_Builtin:
error(node, "'using' cannot be applied to a procedure");
break;
case Entity_Nil:
error(node, "'using' cannot be applied to 'nil'");
break;
case Entity_Label:
error(node, "'using' cannot be applied to a label");
break;
case Entity_Invalid:
error(node, "'using' cannot be applied to an invalid entity");
break;
default:
GB_PANIC("TODO(bill): 'using' other expressions?");
}
case_end;
case_ast_node(pa, PushContext, node);
Operand op = {};
check_expr(c, &op, pa->expr);
check_assignment(c, &op, t_context, str_lit("argument to context <-"));
check_stmt(c, pa->body, mod_flags);
case_end;
case_ast_node(fb, ForeignBlockDecl, node);
AstNode *foreign_library = fb->foreign_library;
CheckerContext prev_context = c->context;
defer (c->context = prev_context);
if (foreign_library->kind != AstNode_Ident) {
error(foreign_library, "foreign library name must be an identifier");
} else {
c->context.foreign_context.curr_library = foreign_library;
c->context.foreign_context.default_cc = ProcCC_CDecl;
}
check_decl_attributes(c, fb->attributes, foreign_block_decl_attribute, nullptr);
for_array(i, fb->decls) {
AstNode *decl = fb->decls[i];
if (decl->kind == AstNode_ValueDecl && decl->ValueDecl.is_mutable) {
check_stmt(c, decl, flags);
}
}
case_end;
case_ast_node(vd, ValueDecl, node);
if (vd->is_mutable) {
Entity **entities = gb_alloc_array(c->allocator, Entity *, vd->names.count);
isize entity_count = 0;
isize new_name_count = 0;
for_array(i, vd->names) {
AstNode *name = vd->names[i];
Entity *entity = nullptr;
if (name->kind != AstNode_Ident) {
error(name, "A variable declaration must be an identifier");
} else {
Token token = name->Ident.token;
String str = token.string;
Entity *found = nullptr;
// NOTE(bill): Ignore assignments to '_'
if (!is_blank_ident(str)) {
found = current_scope_lookup_entity(c->context.scope, str);
new_name_count += 1;
}
if (found == nullptr) {
entity = make_entity_variable(c->allocator, c->context.scope, token, nullptr, false);
entity->identifier = name;
AstNode *fl = c->context.foreign_context.curr_library;
if (fl != nullptr) {
GB_ASSERT(fl->kind == AstNode_Ident);
entity->Variable.is_foreign = true;
entity->Variable.foreign_library_ident = fl;
}
} else {
TokenPos pos = found->token.pos;
error(token,
"Redeclaration of '%.*s' in this scope\n"
"\tat %.*s(%td:%td)",
LIT(str), LIT(pos.file), pos.line, pos.column);
entity = found;
}
}
if (entity == nullptr) {
entity = make_entity_dummy_variable(c->allocator, c->global_scope, ast_node_token(name));
}
entity->parent_proc_decl = c->context.curr_proc_decl;
entities[entity_count++] = entity;
}
if (new_name_count == 0) {
error(node, "No new declarations on the lhs");
}
Type *init_type = nullptr;
if (vd->type != nullptr) {
init_type = check_type(c, vd->type, nullptr);
if (init_type == nullptr) {
init_type = t_invalid;
} else if (is_type_polymorphic(base_type(init_type))) {
gbString str = type_to_string(init_type);
error(vd->type, "Invalid use of a polymorphic type '%s' in variable declaration", str);
gb_string_free(str);
init_type = t_invalid;
} else if (is_type_empty_union(init_type)) {
gbString str = type_to_string(init_type);
error(vd->type, "An empty union '%s' cannot be instantiated in variable declaration", str);
gb_string_free(str);
init_type = t_invalid;
}
}
// TODO NOTE(bill): This technically checks things multple times
AttributeContext ac = make_attribute_context(c->context.foreign_context.link_prefix);
check_decl_attributes(c, vd->attributes, var_decl_attribute, &ac);
for (isize i = 0; i < entity_count; i++) {
Entity *e = entities[i];
GB_ASSERT(e != nullptr);
if (e->flags & EntityFlag_Visited) {
e->type = t_invalid;
continue;
}
e->flags |= EntityFlag_Visited;
if (e->type == nullptr) {
e->type = init_type;
}
ac.link_name = handle_link_name(c, e->token, ac.link_name, ac.link_prefix);
e->Variable.thread_local_model = ac.thread_local_model;
if (ac.link_name.len > 0) {
e->Variable.link_name = ac.link_name;
}
}
check_arity_match(c, vd);
check_init_variables(c, entities, entity_count, vd->values, str_lit("variable declaration"));
for (isize i = 0; i < entity_count; i++) {
Entity *e = entities[i];
if (e->Variable.is_foreign) {
if (vd->values.count > 0) {
error(e->token, "A foreign variable declaration cannot have a default value");
}
String name = e->token.string;
if (e->Variable.link_name.len > 0) {
name = e->Variable.link_name;
}
if (vd->values.count > 0) {
error(e->token, "A foreign variable declaration cannot have a default value");
}
init_entity_foreign_library(c, e);
auto *fp = &c->info.foreigns;
HashKey key = hash_string(name);
Entity **found = map_get(fp, key);
if (found) {
Entity *f = *found;
TokenPos pos = f->token.pos;
Type *this_type = base_type(e->type);
Type *other_type = base_type(f->type);
if (!are_types_identical(this_type, other_type)) {
error(e->token,
"Foreign entity '%.*s' previously declared elsewhere with a different type\n"
"\tat %.*s(%td:%td)",
LIT(name), LIT(pos.file), pos.line, pos.column);
}
} else {
map_set(fp, key, e);
}
}
add_entity(c, c->context.scope, e->identifier, e);
}
if (vd->is_using != 0) {
Token token = ast_node_token(node);
if (vd->type != nullptr && entity_count > 1) {
error(token, "'using' can only be applied to one variable of the same type");
// TODO(bill): Should a 'continue' happen here?
}
for (isize entity_index = 0; entity_index < entity_count; entity_index++) {
Entity *e = entities[entity_index];
if (e == nullptr) {
continue;
}
if (e->kind != Entity_Variable) {
continue;
}
bool is_immutable = e->Variable.is_immutable;
String name = e->token.string;
Type *t = base_type(type_deref(e->type));
if (is_blank_ident(name)) {
error(token, "'using' cannot be applied variable declared as '_'");
} else if (is_type_struct(t) || is_type_raw_union(t)) {
Scope *scope = scope_of_node(&c->info, t->Struct.node);
for_array(i, scope->elements.entries) {
Entity *f = scope->elements.entries[i].value;
if (f->kind == Entity_Variable) {
Entity *uvar = make_entity_using_variable(c->allocator, e, f->token, f->type);
uvar->Variable.is_immutable = is_immutable;
Entity *prev = scope_insert_entity(c->context.scope, uvar);
if (prev != nullptr) {
error(token, "Namespace collision while 'using' '%.*s' of: %.*s", LIT(name), LIT(prev->token.string));
return;
}
}
}
} else {
// NOTE(bill): skip the rest to remove extra errors
error(token, "'using' can only be applied to variables of type struct or raw_union");
return;
}
}
}
} else {
// constant value declarations
}
case_end;
}
}