Minor change to handling of propagation of errors with `---` as a value

src/check_decl.cpp

@@ -70,13 +70,12 @@ gb_internal Type *check_init_variable(CheckerContext *ctx, Entity *e, Operand *o
 		// NOTE(bill): Use the type of the operand
 		Type *t = operand->type;
 		if (is_type_untyped(t)) {
-			if (t == t_invalid || is_type_untyped_nil(t)) {
-				error(e->token, "Invalid use of untyped nil in %.*s", LIT(context_name));
+			if (is_type_untyped_uninit(t)) {
+				error(e->token, "Invalid use of --- in %.*s", LIT(context_name));
 				e->type = t_invalid;
 				return nullptr;
-			}
-			if (t == t_invalid || is_type_untyped_undef(t)) {
-				error(e->token, "Invalid use of --- in %.*s", LIT(context_name));
+			} else if (t == t_invalid || is_type_untyped_nil(t)) {
+				error(e->token, "Invalid use of untyped nil in %.*s", LIT(context_name));
 				e->type = t_invalid;
 				return nullptr;
 			}

src/check_expr.cpp

@@ -646,11 +646,8 @@ gb_internal i64 check_distance_between_types(CheckerContext *c, Operand *operand
 	Type *src = base_type(s);
 	Type *dst = base_type(type);
 
-	if (is_type_untyped_undef(src)) {
-		if (type_has_undef(dst)) {
-			return 1;
-		}
-		return -1;
+	if (is_type_untyped_uninit(src)) {
+		return 1;
 	}
 
 	if (is_type_untyped_nil(src)) {
@@ -993,13 +990,13 @@ gb_internal void check_assignment(CheckerContext *c, Operand *operand, Type *typ
 	if (is_type_untyped(operand->type)) {
 		Type *target_type = type;
 		if (type == nullptr || is_type_any(type)) {
-			if (type == nullptr && is_type_untyped_nil(operand->type)) {
-				error(operand->expr, "Use of untyped nil in %.*s", LIT(context_name));
+			if (type == nullptr && is_type_untyped_uninit(operand->type)) {
+				error(operand->expr, "Use of --- in %.*s", LIT(context_name));
 				operand->mode = Addressing_Invalid;
 				return;
 			}
-			if (type == nullptr && is_type_untyped_undef(operand->type)) {
-				error(operand->expr, "Use of --- in %.*s", LIT(context_name));
+			if (type == nullptr && is_type_untyped_nil(operand->type)) {
+				error(operand->expr, "Use of untyped nil in %.*s", LIT(context_name));
 				operand->mode = Addressing_Invalid;
 				return;
 			}
@@ -3969,7 +3966,7 @@ gb_internal void convert_to_typed(CheckerContext *c, Operand *operand, Type *tar
 		
 
 	case Type_Union:
-		if (!is_operand_nil(*operand) && !is_operand_undef(*operand)) {
+		if (!is_operand_nil(*operand) && !is_operand_uninit(*operand)) {
 			TEMPORARY_ALLOCATOR_GUARD();
 
 			isize count = t->Union.variants.count;
@@ -4036,8 +4033,8 @@ gb_internal void convert_to_typed(CheckerContext *c, Operand *operand, Type *tar
 				error_line("\n\n");
 
 				return;
-			} else if (is_type_untyped_undef(operand->type) && type_has_undef(target_type)) {
-				target_type = t_untyped_undef;
+			} else if (is_type_untyped_uninit(operand->type)) {
+				target_type = t_untyped_uninit;
 			} else if (!is_type_untyped_nil(operand->type) || !type_has_nil(target_type)) {
 				begin_error_block();
 				defer (end_error_block());
@@ -4070,8 +4067,8 @@ gb_internal void convert_to_typed(CheckerContext *c, Operand *operand, Type *tar
 
 
 	default:
-		if (is_type_untyped_undef(operand->type) && type_has_undef(target_type)) {
-			target_type = t_untyped_undef;
+		if (is_type_untyped_uninit(operand->type)) {
+			target_type = t_untyped_uninit;
 		} else if (is_type_untyped_nil(operand->type) && type_has_nil(target_type)) {
 			target_type = t_untyped_nil;
 		} else {
@@ -4083,8 +4080,8 @@ gb_internal void convert_to_typed(CheckerContext *c, Operand *operand, Type *tar
 	}
 	
 	if (is_type_any(target_type) && is_type_untyped(operand->type)) {
-		if (is_type_untyped_nil(operand->type) && is_type_untyped_undef(operand->type)) {
-				
+		if (is_type_untyped_nil(operand->type) && is_type_untyped_uninit(operand->type)) {
+
 		} else {
 			target_type = default_type(operand->type);
 		}
@@ -5197,9 +5194,9 @@ gb_internal bool check_unpack_arguments(CheckerContext *ctx, Entity **lhs, isize
 		}
 
 		Ast *rhs_expr = unparen_expr(rhs[i]);
-		if (allow_undef && rhs_expr != nullptr && rhs_expr->kind == Ast_Undef) {
+		if (allow_undef && rhs_expr != nullptr && rhs_expr->kind == Ast_Uninit) {
 			// NOTE(bill): Just handle this very specific logic here
-			o.type = t_untyped_undef;
+			o.type = t_untyped_uninit;
 			o.mode = Addressing_Value;
 			o.expr = rhs[i];
 			add_type_and_value(c, rhs[i], o.mode, o.type, o.value);
@@ -7167,11 +7164,11 @@ gb_internal bool check_set_index_data(Operand *o, Type *t, bool indirection, i64
 }
 
 gb_internal bool ternary_compare_types(Type *x, Type *y) {
-	if (is_type_untyped_undef(x) && type_has_undef(y)) {
+	if (is_type_untyped_uninit(x)) {
 		return true;
 	} else if (is_type_untyped_nil(x) && type_has_nil(y)) {
 		return true;
-	} else if (is_type_untyped_undef(y) && type_has_undef(x)) {
+	} else if (is_type_untyped_uninit(y)) {
 		return true;
 	} else if (is_type_untyped_nil(y) && type_has_nil(x)) {
 		return true;
@@ -7708,7 +7705,7 @@ gb_internal ExprKind check_ternary_if_expr(CheckerContext *c, Operand *o, Ast *n
 	}
 
 	o->type = x.type;
-	if (is_type_untyped_nil(o->type) || is_type_untyped_undef(o->type)) {
+	if (is_type_untyped_nil(o->type) || is_type_untyped_uninit(o->type)) {
 		o->type = y.type;
 	}
 
@@ -9601,9 +9598,9 @@ gb_internal ExprKind check_expr_base_internal(CheckerContext *c, Operand *o, Ast
 		check_ident(c, o, node, nullptr, type_hint, false);
 	case_end;
 
-	case_ast_node(u, Undef, node);
+	case_ast_node(u, Uninit, node);
 		o->mode = Addressing_Value;
-		o->type = t_untyped_undef;
+		o->type = t_untyped_uninit;
 		error(node, "Use of --- outside of variable declaration");
 	case_end;
 
@@ -10167,7 +10164,7 @@ gb_internal gbString write_expr_to_string(gbString str, Ast *node, bool shorthan
 		str = string_append_string(str, bd->name.string);
 	case_end;
 
-	case_ast_node(ud, Undef, node);
+	case_ast_node(ud, Uninit, node);
 		str = gb_string_appendc(str, "---");
 	case_end;
 

src/check_type.cpp

@@ -135,7 +135,7 @@ gb_internal void check_struct_fields(CheckerContext *ctx, Ast *node, Slice<Entit
 			type = t_invalid;
 		}
 		if (is_type_untyped(type)) {
-			if (is_type_untyped_undef(type)) {
+			if (is_type_untyped_uninit(type)) {
 				error(params[i], "Cannot determine parameter type from ---");
 			} else {
 				error(params[i], "Cannot determine parameter type from a nil");
@@ -473,7 +473,7 @@ gb_internal Type *check_record_polymorphic_params(CheckerContext *ctx, Ast *poly
 				type = t_invalid;
 			}
 			if (is_type_untyped(type)) {
-				if (is_type_untyped_undef(type)) {
+				if (is_type_untyped_uninit(type)) {
 					error(params[i], "Cannot determine parameter type from ---");
 				} else {
 					error(params[i], "Cannot determine parameter type from a nil");
@@ -1528,7 +1528,7 @@ gb_internal Type *check_get_params(CheckerContext *ctx, Scope *scope, Ast *_para
 			type = t_invalid;
 		}
 		if (is_type_untyped(type)) {
-			if (is_type_untyped_undef(type)) {
+			if (is_type_untyped_uninit(type)) {
 				error(param, "Cannot determine parameter type from ---");
 			} else {
 				error(param, "Cannot determine parameter type from a nil");

src/checker.cpp

@@ -27,8 +27,8 @@ gb_internal bool is_operand_value(Operand o) {
 gb_internal bool is_operand_nil(Operand o) {
 	return o.mode == Addressing_Value && o.type == t_untyped_nil;
 }
-gb_internal bool is_operand_undef(Operand o) {
-	return o.mode == Addressing_Value && o.type == t_untyped_undef;
+gb_internal bool is_operand_uninit(Operand o) {
+	return o.mode == Addressing_Value && o.type == t_untyped_uninit;
 }
 
 gb_internal bool check_rtti_type_disallowed(Token const &token, Type *type, char const *format) {

src/llvm_backend.cpp

@@ -1129,12 +1129,7 @@ gb_internal lbProcedure *lb_create_startup_runtime(lbModule *main_module, lbProc
 			lbValue init = lb_build_expr(p, init_expr);
 			if (init.value == nullptr) {
 				LLVMTypeRef global_type = llvm_addr_type(p->module, var.var);
-				if (is_type_untyped_undef(init.type)) {
-					// LLVMSetInitializer(var.var.value, LLVMGetUndef(global_type));
-					LLVMSetInitializer(var.var.value, LLVMConstNull(global_type));
-					var.is_initialized = true;
-					continue;
-				} else if (is_type_untyped_nil(init.type)) {
+				if (is_type_untyped_nil(init.type)) {
 					LLVMSetInitializer(var.var.value, LLVMConstNull(global_type));
 					var.is_initialized = true;
 					continue;
@@ -2363,8 +2358,7 @@ gb_internal bool lb_generate_code(lbGenerator *gen) {
 					}
 				}
 			}
-			if (!var.is_initialized &&
-			    (is_type_untyped_nil(tav.type) || is_type_untyped_undef(tav.type))) {
+			if (!var.is_initialized && is_type_untyped_nil(tav.type)) {
 				var.is_initialized = true;
 			}
 		}

src/llvm_backend_const.cpp

@@ -1,6 +1,6 @@
 gb_internal bool lb_is_const(lbValue value) {
 	LLVMValueRef v = value.value;
-	if (is_type_untyped_nil(value.type) || is_type_untyped_undef(value.type)) {
+	if (is_type_untyped_nil(value.type)) {
 		// TODO(bill): Is this correct behaviour?
 		return true;
 	}

src/llvm_backend_debug.cpp

@@ -282,7 +282,7 @@ gb_internal LLVMMetadataRef lb_debug_type_internal(lbModule *m, Type *type) {
 		case Basic_UntypedString:     GB_PANIC("Basic_UntypedString");     break;
 		case Basic_UntypedRune:       GB_PANIC("Basic_UntypedRune");       break;
 		case Basic_UntypedNil:        GB_PANIC("Basic_UntypedNil");        break;
-		case Basic_UntypedUndef:      GB_PANIC("Basic_UntypedUndef");      break;
+		case Basic_UntypedUninit:     GB_PANIC("Basic_UntypedUninit");     break;
 
 		default: GB_PANIC("Basic Unhandled"); break;
 		}

src/llvm_backend_expr.cpp

@@ -1486,12 +1486,12 @@ gb_internal lbValue lb_emit_conv(lbProcedure *p, lbValue value, Type *t) {
 	GB_ASSERT(src != nullptr);
 	GB_ASSERT(dst != nullptr);
 
+	if (is_type_untyped_uninit(src)) {
+		return lb_const_undef(m, t);
+	}
 	if (is_type_untyped_nil(src)) {
 		return lb_const_nil(m, t);
 	}
-	if (is_type_untyped_undef(src)) {
-		return lb_const_undef(m, t);
-	}
 
 	if (LLVMIsConstant(value.value)) {
 		if (is_type_any(dst)) {
@@ -2132,12 +2132,12 @@ gb_internal lbValue lb_emit_conv(lbProcedure *p, lbValue value, Type *t) {
 
 
 	if (is_type_any(dst)) {
+		if (is_type_untyped_uninit(src)) {
+			return lb_const_undef(p->module, t);
+		}
 		if (is_type_untyped_nil(src)) {
 			return lb_const_nil(p->module, t);
 		}
-		if (is_type_untyped_undef(src)) {
-			return lb_const_undef(p->module, t);
-		}
 
 		lbAddr result = lb_add_local_generated(p, t, true);
 
@@ -3136,11 +3136,11 @@ gb_internal lbValue lb_build_expr_internal(lbProcedure *p, Ast *expr) {
 		return lb_addr_load(p, lb_build_addr(p, expr));
 	case_end;
 
-	case_ast_node(u, Undef, expr)
+	case_ast_node(u, Uninit, expr)
 		lbValue res = {};
 		if (is_type_untyped(type)) {
 			res.value = nullptr;
-			res.type  = t_untyped_undef;
+			res.type  = t_untyped_uninit;
 		} else {
 			res.value = LLVMGetUndef(lb_type(m, type));
 			res.type  = type;

src/llvm_backend_general.cpp

@@ -677,7 +677,7 @@ gb_internal void lb_addr_store(lbProcedure *p, lbAddr addr, lbValue value) {
 		return;
 	}
 	GB_ASSERT(value.type != nullptr);
-	if (is_type_untyped_undef(value.type)) {
+	if (is_type_untyped_uninit(value.type)) {
 		Type *t = lb_addr_type(addr);
 		value.type = t;
 		value.value = LLVMGetUndef(lb_type(p->module, t));
@@ -1828,7 +1828,7 @@ gb_internal LLVMTypeRef lb_type_internal(lbModule *m, Type *type) {
 		case Basic_UntypedString:     GB_PANIC("Basic_UntypedString"); break;
 		case Basic_UntypedRune:       GB_PANIC("Basic_UntypedRune"); break;
 		case Basic_UntypedNil:        GB_PANIC("Basic_UntypedNil"); break;
-		case Basic_UntypedUndef:      GB_PANIC("Basic_UntypedUndef"); break;
+		case Basic_UntypedUninit:     GB_PANIC("Basic_UntypedUninit"); break;
 		}
 		break;
 	case Type_Named:

src/llvm_backend_proc.cpp

@@ -3218,10 +3218,10 @@ gb_internal lbValue lb_build_call_expr_internal(lbProcedure *p, Ast *expr) {
 			Entity *e = params->variables[i];
 			if (args[i].type == nullptr) {
 				continue;
+			} else if (is_type_untyped_uninit(args[i].type)) {
+				args[i] = lb_const_undef(m, e->type);
 			} else if (is_type_untyped_nil(args[i].type)) {
 				args[i] = lb_const_nil(m, e->type);
-			} else if (is_type_untyped_undef(args[i].type)) {
-				args[i] = lb_const_undef(m, e->type);
 			}
 		}
 
@@ -3409,10 +3409,10 @@ gb_internal lbValue lb_build_call_expr_internal(lbProcedure *p, Ast *expr) {
 			Entity *e = param_tuple->variables[i];
 			if (args[i].type == nullptr) {
 				continue;
+			} else if (is_type_untyped_uninit(args[i].type)) {
+				args[i] = lb_const_undef(m, e->type);
 			} else if (is_type_untyped_nil(args[i].type)) {
 				args[i] = lb_const_nil(m, e->type);
-			} else if (is_type_untyped_undef(args[i].type)) {
-				args[i] = lb_const_undef(m, e->type);
 			}
 		}
 	}

src/parser.cpp

@@ -115,7 +115,7 @@ gb_internal Ast *clone_ast(Ast *node, AstFile *f) {
 		n->Ident.entity = nullptr;
 		break;
 	case Ast_Implicit:       break;
-	case Ast_Undef:          break;
+	case Ast_Uninit:         break;
 	case Ast_BasicLit:       break;
 	case Ast_BasicDirective: break;
 
@@ -646,9 +646,9 @@ gb_internal Ast *ast_implicit(AstFile *f, Token token) {
 	result->Implicit = token;
 	return result;
 }
-gb_internal Ast *ast_undef(AstFile *f, Token token) {
-	Ast *result = alloc_ast_node(f, Ast_Undef);
-	result->Undef = token;
+gb_internal Ast *ast_uninit(AstFile *f, Token token) {
+	Ast *result = alloc_ast_node(f, Ast_Uninit);
+	result->Uninit = token;
 	return result;
 }
 
@@ -2092,8 +2092,8 @@ gb_internal Ast *parse_operand(AstFile *f, bool lhs) {
 	case Token_Ident:
 		return parse_ident(f);
 
-	case Token_Undef:
-		return ast_undef(f, expect_token(f, Token_Undef));
+	case Token_Uninit:
+		return ast_uninit(f, expect_token(f, Token_Uninit));
 
 	case Token_context:
 		return ast_implicit(f, expect_token(f, Token_context));
@@ -2292,7 +2292,7 @@ gb_internal Ast *parse_operand(AstFile *f, bool lhs) {
 
 		skip_possible_newline_for_literal(f);
 
-		if (allow_token(f, Token_Undef)) {
+		if (allow_token(f, Token_Uninit)) {
 			if (where_token.kind != Token_Invalid) {
 				syntax_error(where_token, "'where' clauses are not allowed on procedure literals without a defined body (replaced with ---)");
 			}

src/parser.hpp

@@ -373,7 +373,7 @@ gb_global char const *union_type_kind_strings[UnionType_COUNT] = {
 		Entity *entity; \
 	}) \
 	AST_KIND(Implicit,       "implicit",        Token) \
-	AST_KIND(Undef,          "undef",           Token) \
+	AST_KIND(Uninit,         "uninitialized value", Token) \
 	AST_KIND(BasicLit,       "basic literal",   struct { \
 		Token token; \
 	}) \

src/parser_pos.cpp

@@ -2,7 +2,7 @@ gb_internal Token ast_token(Ast *node) {
 	switch (node->kind) {
 	case Ast_Ident:          return node->Ident.token;
 	case Ast_Implicit:       return node->Implicit;
-	case Ast_Undef:          return node->Undef;
+	case Ast_Uninit:         return node->Uninit;
 	case Ast_BasicLit:       return node->BasicLit.token;
 	case Ast_BasicDirective: return node->BasicDirective.token;
 	case Ast_ProcGroup:      return node->ProcGroup.token;
@@ -137,7 +137,7 @@ Token ast_end_token(Ast *node) {
 		return empty_token;
 	case Ast_Ident:          return node->Ident.token;
 	case Ast_Implicit:       return node->Implicit;
-	case Ast_Undef:          return node->Undef;
+	case Ast_Uninit:         return node->Uninit;
 	case Ast_BasicLit:       return node->BasicLit.token;
 	case Ast_BasicDirective: return node->BasicDirective.token;
 	case Ast_ProcGroup:      return node->ProcGroup.close;

src/tokenizer.cpp

@@ -54,7 +54,7 @@ TOKEN_KIND(Token__AssignOpEnd, ""), \
 	TOKEN_KIND(Token_Increment, "++"), \
 	TOKEN_KIND(Token_Decrement, "--"), \
 	TOKEN_KIND(Token_ArrowRight,"->"), \
-	TOKEN_KIND(Token_Undef,     "---"), \
+	TOKEN_KIND(Token_Uninit,    "---"), \
 \
 TOKEN_KIND(Token__ComparisonBegin, ""), \
 	TOKEN_KIND(Token_CmpEq, "=="), \
@@ -917,7 +917,7 @@ gb_internal void tokenizer_get_token(Tokenizer *t, Token *token, int repeat=0) {
 				token->kind = Token_Decrement;
 				if (t->curr_rune == '-') {
 					advance_to_next_rune(t);
-					token->kind = Token_Undef;
+					token->kind = Token_Uninit;
 				}
 				break;
 			case '>':
@@ -1078,7 +1078,7 @@ semicolon_check:;
 	case Token_Imag:
 	case Token_Rune:
 	case Token_String:
-	case Token_Undef:
+	case Token_Uninit:
 		/*fallthrough*/
 	case Token_Question:
 	case Token_Pointer:

src/types.cpp

@@ -83,7 +83,7 @@ enum BasicKind {
 	Basic_UntypedString,
 	Basic_UntypedRune,
 	Basic_UntypedNil,
-	Basic_UntypedUndef,
+	Basic_UntypedUninit,
 
 	Basic_COUNT,
 
@@ -515,7 +515,7 @@ gb_global Type basic_types[] = {
 	{Type_Basic, {Basic_UntypedString,     BasicFlag_String     | BasicFlag_Untyped,   0, STR_LIT("untyped string")}},
 	{Type_Basic, {Basic_UntypedRune,       BasicFlag_Integer    | BasicFlag_Untyped,   0, STR_LIT("untyped rune")}},
 	{Type_Basic, {Basic_UntypedNil,        BasicFlag_Untyped,                          0, STR_LIT("untyped nil")}},
-	{Type_Basic, {Basic_UntypedUndef,      BasicFlag_Untyped,                          0, STR_LIT("untyped undefined")}},
+	{Type_Basic, {Basic_UntypedUninit,     BasicFlag_Untyped,                          0, STR_LIT("untyped uninitialized")}},
 };
 
 // gb_global Type basic_type_aliases[] = {
@@ -589,7 +589,7 @@ gb_global Type *t_untyped_quaternion = &basic_types[Basic_UntypedQuaternion];
 gb_global Type *t_untyped_string     = &basic_types[Basic_UntypedString];
 gb_global Type *t_untyped_rune       = &basic_types[Basic_UntypedRune];
 gb_global Type *t_untyped_nil        = &basic_types[Basic_UntypedNil];
-gb_global Type *t_untyped_undef      = &basic_types[Basic_UntypedUndef];
+gb_global Type *t_untyped_uninit     = &basic_types[Basic_UntypedUninit];
 
 
 
@@ -1866,14 +1866,15 @@ gb_internal bool is_type_typeid(Type *t) {
 }
 gb_internal bool is_type_untyped_nil(Type *t) {
 	t = base_type(t);
-	return (t->kind == Type_Basic && t->Basic.kind == Basic_UntypedNil);
+	// NOTE(bill): checking for `nil` or `---` at once is just to improve the error handling
+	return (t->kind == Type_Basic && (t->Basic.kind == Basic_UntypedNil || t->Basic.kind == Basic_UntypedUninit));
 }
-gb_internal bool is_type_untyped_undef(Type *t) {
+gb_internal bool is_type_untyped_uninit(Type *t) {
 	t = base_type(t);
-	return (t->kind == Type_Basic && t->Basic.kind == Basic_UntypedUndef);
+	// NOTE(bill): checking for `nil` or `---` at once is just to improve the error handling
+	return (t->kind == Type_Basic && t->Basic.kind == Basic_UntypedUninit);
 }
 
-
 gb_internal bool is_type_empty_union(Type *t) {
 	t = base_type(t);
 	return t->kind == Type_Union && t->Union.variants.count == 0;
@@ -2206,10 +2207,6 @@ gb_internal bool is_type_polymorphic(Type *t, bool or_specialized=false) {
 }
 
 
-gb_internal gb_inline bool type_has_undef(Type *t) {
-	return true;
-}
-
 gb_internal bool type_has_nil(Type *t) {
 	t = base_type(t);
 	switch (t->kind) {