Update to fix with splat.

src/compiler/ast.c

@@ -315,6 +315,11 @@ void decl_append_links_to_global_during_codegen(Decl *decl)
 	}
 }
 
+bool decl_is_defaulted_var(Decl *decl)
+{
+	return decl->decl_kind == DECL_VAR && decl->var.no_init && decl->var.defaulted;
+}
+
 /*
  * Count the expected number of elements needed for an initializer
  * by folding any anonymous structs and unions.

src/compiler/compiler_internal.h

@@ -2324,6 +2324,7 @@ const char *decl_safe_name(Decl *decl);
 const char *decl_to_name(Decl *decl);
 const char *decl_to_a_name(Decl *decl);
 int decl_count_elements(Decl *structlike);
+bool decl_is_defaulted_var(Decl *decl);
 void decl_append_links_to_global_during_codegen(Decl *decl);
 
 INLINE bool decl_ok(Decl *decl);

src/compiler/sema_expr.c

@@ -1281,10 +1281,13 @@ static inline bool sema_expr_analyse_identifier(SemaContext *context, Type *to,
 				default:
 					UNREACHABLE
 			}
-			SEMA_ERROR(expr, message);
-			return false;
+			RETURN_SEMA_ERROR(expr, message);
 		}
 	}
+	if (decl_is_defaulted_var(decl))
+	{
+		RETURN_SEMA_ERROR(expr, "The parameter '%s' was not provided by the caller.", decl->name);
+	}
 	if (decl->resolve_status != RESOLVE_DONE)
 	{
 		if (!sema_analyse_decl(context, decl)) return decl_poison(decl);
@@ -1348,6 +1351,10 @@ static inline bool sema_expr_resolve_ct_identifier(SemaContext *context, Expr *e
 		return expr_poison(expr);
 	}
 
+	if (decl_is_defaulted_var(decl))
+	{
+		RETURN_SEMA_ERROR(expr, "The parameter '%s' was not provided by the caller.", decl->name);
+	}
 	ASSERT_SPAN(expr, decl->decl_kind == DECL_VAR);
 	ASSERT_SPAN(expr, decl->resolve_status == RESOLVE_DONE);
 
@@ -1830,7 +1837,7 @@ static SplatResult sema_splat_optional_argument(SemaContext *context, Expr *expr
 	if (!candidate->var.no_init) return SPLAT_NONE;
 	// We found it, it's a valid variable.
 	Decl *local = sema_find_local(context, candidate->name);
-	if (local && local->var.kind == candidate->var.kind) return SPLAT_ONE;
+	if (local && local->var.kind == candidate->var.kind && !decl_is_defaulted_var(local)) return SPLAT_ONE;
 	// It's missing! Let's splat-zero
 	return SPLAT_ZERO;
 }
@@ -2923,8 +2930,8 @@ bool sema_expr_analyse_macro_call(SemaContext *context, Expr *call_expr, Expr *s
 	{
 		// Skip raw vararg
 		if (!param) continue;
-		if (param->var.no_init && param->var.defaulted) continue;
 		if (!sema_add_local(&macro_context, param)) goto EXIT_FAIL;
+		if (param->var.no_init && param->var.defaulted) continue;
 		if (param->var.init_expr)
 		{
 			Type *param_type = param->type;
@@ -6854,6 +6861,10 @@ static bool sema_expr_fold_hash(SemaContext *context, Expr *expr)
 		ASSERT_SPAN(expr, decl->decl_kind == DECL_VAR);
 		DEBUG_LOG("Replacing expr (%p) with '%s' (%p) expression resolve: %d", expr, expr_kind_to_string(decl->var.init_expr->expr_kind), decl->var.init_expr, decl->var.init_expr->resolve_status);
 		bool is_ref = expr->hash_ident_expr.is_ref;
+		if (decl_is_defaulted_var(decl))
+		{
+			RETURN_SEMA_ERROR(expr, "The parameter '%s' was not provided by the caller.", decl->name);
+		}
 		expr_replace(expr, copy_expr_single(decl->var.init_expr));
 		if (is_ref) expr_set_to_ref(expr);
 		REMINDER("Handle inlining at");
@@ -10756,7 +10767,7 @@ static inline bool sema_expr_analyse_ct_defined(SemaContext *context, Expr *expr
 		{
 			Decl *decl = sema_find_path_symbol(active_context, main_expr->unresolved_ident_expr.ident, main_expr->unresolved_ident_expr.path);
 			if (!decl_ok(decl)) goto FAIL;
-			success = decl != NULL;
+			success = decl != NULL && !decl_is_defaulted_var(decl);
 			break;
 		}
 		case EXPR_HASH_IDENT:
@@ -10765,6 +10776,11 @@ static inline bool sema_expr_analyse_ct_defined(SemaContext *context, Expr *expr
 			{
 				Decl *decl = sema_resolve_symbol(active_context, main_expr->hash_ident_expr.identifier, NULL, main_expr->span);
 				if (!decl) goto FAIL;
+				if (decl_is_defaulted_var(decl))
+				{
+					success = false;
+					break;
+				}
 				bool is_ref = main_expr->hash_ident_expr.is_ref;
 				main_expr = copy_expr_single(decl->var.init_expr);
 				if (is_ref) expr_set_to_ref(main_expr);
@@ -10772,7 +10788,7 @@ static inline bool sema_expr_analyse_ct_defined(SemaContext *context, Expr *expr
 			}
 			Decl *decl = sema_find_symbol(active_context, main_expr->hash_ident_expr.identifier);
 			if (!decl_ok(decl)) goto FAIL;
-			success = decl != NULL;
+			success = decl != NULL && !decl_is_defaulted_var(decl);
 			break;
 		}
 		case EXPR_COMPILER_CONST:
@@ -10837,7 +10853,7 @@ static inline bool sema_expr_analyse_ct_defined(SemaContext *context, Expr *expr
 		{
 			Decl *decl = sema_find_symbol(active_context, main_expr->ct_ident_expr.identifier);
 			if (!decl_ok(decl)) goto FAIL;
-			success = decl != NULL;
+			success = decl != NULL && !decl_is_defaulted_var(decl);
 			break;
 		}
 		case EXPR_CALL:

src/compiler/sema_stmts.c

@@ -1217,7 +1217,7 @@ static inline bool sema_analyse_ct_type_assign_stmt(SemaContext *context, Ast *s
 
 	Decl *decl = sema_find_symbol(context, statement->ct_type_assign_stmt.var_name);
 	if (!decl) RETURN_SEMA_ERROR(statement, "'%s' is not defined in this scope yet.", statement->ct_type_assign_stmt.var_name);
-
+	if (decl_is_defaulted_var(decl)) RETURN_SEMA_ERROR(statement, "The parameter '%s' was not provided by the caller.", decl->name);
 	decl->var.init_expr = right;
 	statement->ast_kind = AST_NOP_STMT;
 

src/compiler/sema_types.c

@@ -258,6 +258,10 @@ static bool sema_resolve_type_identifier(SemaContext *context, TypeInfo *type_in
 				Expr *init_expr = decl->var.init_expr;
 				if (!init_expr)
 				{
+					if (decl_is_defaulted_var(decl))
+					{
+						RETURN_SEMA_ERROR(type_info, "The parameter '%s' was not provided by the caller.", decl->name);
+					}
 					RETURN_SEMA_ERROR(type_info, "You need to assign a type to '%s' before using it.", decl->name);
 				}
 				ASSERT_SPAN(init_expr, expr_is_const_typeid(init_expr));

test/test_suite/functions/splat_err.c3

@@ -0,0 +1,62 @@
+import std;
+fn int test1()
+{
+	@test1();
+}
+
+fn int test2()
+{
+	@test2();
+}
+
+fn int test3()
+{
+	@test3();
+}
+
+fn int test4()
+{
+	@test4();
+}
+
+fn void test5()
+{
+	@test5();
+}
+
+fn void test6()
+{
+	@test6();
+}
+
+macro @test1($Foo = ...)
+{
+	return $Foo.typeid; // #error: The parameter '$Foo' was not provided by the caller.
+}
+
+macro @test2(#foo = ...)
+{
+	return #foo; // #error: The parameter '#foo' was not provided by the caller
+}
+
+macro @test3(foo = ...)
+{
+	return foo; // #error: The parameter 'foo' was not provided by the caller.
+}
+
+macro @test4($foo = ...)
+{
+	return $foo; // #error: The parameter '$foo' was not provided by the caller
+}
+
+macro @test5($Foo = ...)
+{
+	$Foo = int; // #error: The parameter '$Foo' was not provided by the caller
+	return $Foo.typeid;
+}
+
+macro @test6(foo = ...)
+{
+	foo = 1; // #error: The parameter 'foo' was not provided by the caller
+	return foo;
+}

test/test_suite/lambda/lambda_splat_macro2.c3t

@@ -0,0 +1,30 @@
+// #target: macos-x64
+module test;
+import std;
+fn int main()
+{
+	bool x = test1a()();
+	return 0;
+}
+
+macro test1a(bool $a = ...) => fn bool()
+{
+	return test1b(...$a);
+};
+macro test1b(bool $a = ...) => $defined($a) ??? $a : false;
+
+
+/* #expect: test.ll
+
+entry:
+  %x = alloca i8, align 1
+  %0 = call i8 @"test.test1a$lambda1"()
+  store i8 %0, ptr %x, align 1
+  ret i32 0
+}
+
+; Function Attrs: nounwind uwtable
+define internal zeroext i8 @"test.test1a$lambda1"() #0 {
+entry:
+  ret i8 0
+}