Add @(require_results)

core/os/dir_windows.odin

@@ -6,6 +6,7 @@ import "base:runtime"
 
 @(require_results)
 read_dir :: proc(fd: Handle, n: int, allocator := context.allocator) -> (fi: []File_Info, err: Error) {
+	@(require_results)
 	find_data_to_file_info :: proc(base_path: string, d: ^win32.WIN32_FIND_DATAW) -> (fi: File_Info) {
 		// Ignore "." and ".."
 		if d.cFileName[0] == '.' && d.cFileName[1] == 0 {

core/os/errors.odin

@@ -139,6 +139,12 @@ _error_string :: proc "contextless" (e: Platform_Error) -> string where intrinsi
 		return ""
 	}
 
+	when ODIN_OS == .Darwin {
+		if s := string(_darwin_string_error(i32(e))); s != "" {
+			return s
+		}
+	}
+
 	when ODIN_OS != .Linux {
 		@(require_results)
 		binary_search :: proc "contextless" (array: $A/[]$T, key: T) -> (index: int, found: bool) #no_bounds_check {

core/os/file_windows.odin

@@ -5,10 +5,12 @@ import "base:intrinsics"
 import "base:runtime"
 import "core:unicode/utf16"
 
+@(require_results)
 is_path_separator :: proc(c: byte) -> bool {
 	return c == '/' || c == '\\'
 }
 
+@(require_results)
 open :: proc(path: string, mode: int = O_RDONLY, perm: int = 0) -> (Handle, Error) {
 	if len(path) == 0 {
 		return INVALID_HANDLE, General_Error.Not_Exist
@@ -96,7 +98,7 @@ write :: proc(fd: Handle, data: []byte) -> (int, Error) {
 	return int(total_write), nil
 }
 
-@(private="file")
+@(private="file", require_results)
 read_console :: proc(handle: win32.HANDLE, b: []byte) -> (n: int, err: Error) {
 	if len(b) == 0 {
 		return 0, nil
@@ -206,6 +208,7 @@ seek :: proc(fd: Handle, offset: i64, whence: int) -> (i64, Error) {
 	return i64(hi)<<32 + i64(dw_ptr), nil
 }
 
+@(require_results)
 file_size :: proc(fd: Handle) -> (i64, Error) {
 	length: win32.LARGE_INTEGER
 	err: Error
@@ -331,6 +334,7 @@ stdout := get_std_handle(uint(win32.STD_OUTPUT_HANDLE))
 stderr := get_std_handle(uint(win32.STD_ERROR_HANDLE))
 
 
+@(require_results)
 get_std_handle :: proc "contextless" (h: uint) -> Handle {
 	fd := win32.GetStdHandle(win32.DWORD(h))
 	return Handle(fd)
@@ -345,6 +349,7 @@ exists :: proc(path: string) -> bool {
 	return attribs != win32.INVALID_FILE_ATTRIBUTES
 }
 
+@(require_results)
 is_file :: proc(path: string) -> bool {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	wpath := win32.utf8_to_wstring(path, context.temp_allocator)
@@ -356,6 +361,7 @@ is_file :: proc(path: string) -> bool {
 	return false
 }
 
+@(require_results)
 is_dir :: proc(path: string) -> bool {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	wpath := win32.utf8_to_wstring(path, context.temp_allocator)
@@ -370,6 +376,7 @@ is_dir :: proc(path: string) -> bool {
 // NOTE(tetra): GetCurrentDirectory is not thread safe with SetCurrentDirectory and GetFullPathName
 @private cwd_lock := win32.SRWLOCK{} // zero is initialized
 
+@(require_results)
 get_current_directory :: proc(allocator := context.allocator) -> string {
 	win32.AcquireSRWLockExclusive(&cwd_lock)
 
@@ -426,7 +433,7 @@ remove_directory :: proc(path: string) -> (err: Error) {
 
 
 
-@(private)
+@(private, require_results)
 is_abs :: proc(path: string) -> bool {
 	if len(path) > 0 && path[0] == '/' {
 		return true
@@ -442,7 +449,7 @@ is_abs :: proc(path: string) -> bool {
 	return false
 }
 
-@(private)
+@(private, require_results)
 fix_long_path :: proc(path: string) -> string {
 	if len(path) < 248 {
 		return path
@@ -574,6 +581,7 @@ remove :: proc(name: string) -> Error {
 }
 
 
+@(require_results)
 pipe :: proc() -> (r, w: Handle, err: Error) {
 	sa: win32.SECURITY_ATTRIBUTES
 	sa.nLength = size_of(win32.SECURITY_ATTRIBUTES)

core/os/os_darwin.odin

@@ -562,13 +562,13 @@ S_ISUID :: 0o4000 // Set user id on execution
 S_ISGID :: 0o2000 // Set group id on execution
 S_ISVTX :: 0o1000 // Directory restrcted delete
 
-S_ISLNK  :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFLNK  }
+@(require_results) S_ISLNK  :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFLNK  }
-S_ISREG  :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFREG  }
+@(require_results) S_ISREG  :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFREG  }
-S_ISDIR  :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFDIR  }
+@(require_results) S_ISDIR  :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFDIR  }
-S_ISCHR  :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFCHR  }
+@(require_results) S_ISCHR  :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFCHR  }
-S_ISBLK  :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFBLK  }
+@(require_results) S_ISBLK  :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFBLK  }
-S_ISFIFO :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFIFO  }
+@(require_results) S_ISFIFO :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFIFO  }
-S_ISSOCK :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFSOCK }
+@(require_results) S_ISSOCK :: #force_inline proc(m: u16) -> bool { return (m & S_IFMT) == S_IFSOCK }
 
 R_OK :: 4 // Test for read permission
 W_OK :: 2 // Test for write permission
@@ -667,11 +667,13 @@ get_last_error :: proc "contextless" () -> Error {
 	return Platform_Error(__error()^)
 }
 
+@(require_results)
 get_last_error_string :: proc() -> string {
 	return string(_darwin_string_error(__error()^))
 }
 
 
+@(require_results)
 open :: proc(path: string, flags: int = O_RDWR, mode: int = 0) -> (handle: Handle, err: Error) {
 	isDir := is_dir_path(path)
 	flags := flags
@@ -790,6 +792,7 @@ seek :: proc(fd: Handle, offset: i64, whence: int) -> (i64, Error) {
 	return final_offset, nil
 }
 
+@(require_results)
 file_size :: proc(fd: Handle) -> (i64, Error) {
 	prev, _   := seek(fd, 0, SEEK_CUR)
 	size, err := seek(fd, 0, SEEK_END)
@@ -804,12 +807,14 @@ stdin:  Handle = 0 // get_std_handle(win32.STD_INPUT_HANDLE);
 stdout: Handle = 1 // get_std_handle(win32.STD_OUTPUT_HANDLE);
 stderr: Handle = 2 // get_std_handle(win32.STD_ERROR_HANDLE);
 
+@(require_results)
 last_write_time :: proc(fd: Handle) -> (time: File_Time, err: Error) {
 	s := _fstat(fd) or_return
 	modified := s.modified.seconds * 1_000_000_000 + s.modified.nanoseconds
 	return File_Time(modified), nil
 }
 
+@(require_results)
 last_write_time_by_name :: proc(name: string) -> (time: File_Time, err: Error) {
 	s := _stat(name) or_return
 	modified := s.modified.seconds * 1_000_000_000 + s.modified.nanoseconds
@@ -817,10 +822,12 @@ last_write_time_by_name :: proc(name: string) -> (time: File_Time, err: Error) {
 }
 
 
+@(require_results)
 is_path_separator :: proc(r: rune) -> bool {
 	return r == '/'
 }
 
+@(require_results)
 is_file_handle :: proc(fd: Handle) -> bool {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -829,6 +836,7 @@ is_file_handle :: proc(fd: Handle) -> bool {
 	return S_ISREG(s.mode)
 }
 
+@(require_results)
 is_file_path :: proc(path: string, follow_links: bool = true) -> bool {
 	s: OS_Stat
 	err: Error
@@ -844,6 +852,7 @@ is_file_path :: proc(path: string, follow_links: bool = true) -> bool {
 }
 
 
+@(require_results)
 is_dir_handle :: proc(fd: Handle) -> bool {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -852,6 +861,7 @@ is_dir_handle :: proc(fd: Handle) -> bool {
 	return S_ISDIR(s.mode)
 }
 
+@(require_results)
 is_dir_path :: proc(path: string, follow_links: bool = true) -> bool {
 	s: OS_Stat
 	err: Error
@@ -869,6 +879,7 @@ is_dir_path :: proc(path: string, follow_links: bool = true) -> bool {
 is_file :: proc {is_file_path, is_file_handle}
 is_dir :: proc {is_dir_path, is_dir_handle}
 
+@(require_results)
 exists :: proc(path: string) -> bool {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cpath := strings.clone_to_cstring(path, context.temp_allocator)
@@ -893,7 +904,7 @@ remove :: proc(path: string) -> Error {
 	return nil
 }
 
-@private
+@(private, require_results)
 _stat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -906,7 +917,7 @@ _stat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -919,7 +930,7 @@ _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	s: OS_Stat
 	result := _unix_fstat(fd, &s)
@@ -929,7 +940,7 @@ _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	dirp := _unix_fdopendir(fd)
 	if dirp == cast(Dir)nil {
@@ -938,7 +949,7 @@ _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	return dirp, nil
 }
 
-@private
+@(private)
 _closedir :: proc(dirp: Dir) -> Error {
 	rc := _unix_closedir(dirp)
 	if rc != 0 {
@@ -947,12 +958,12 @@ _closedir :: proc(dirp: Dir) -> Error {
 	return nil
 }
 
-@private
+@(private)
 _rewinddir :: proc(dirp: Dir) {
 	_unix_rewinddir(dirp)
 }
 
-@private
+@(private, require_results)
 _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool) {
 	result: ^Dirent
 	rc := _unix_readdir_r(dirp, &entry, &result)
@@ -971,7 +982,7 @@ _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool)
 	return
 }
 
-@private
+@(private, require_results)
 _readlink :: proc(path: string) -> (string, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == context.allocator)
 	path_cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -994,12 +1005,14 @@ _readlink :: proc(path: string) -> (string, Error) {
 	}
 }
 
+@(require_results)
 absolute_path_from_handle :: proc(fd: Handle) -> (path: string, err: Error) {
 	buf: [DARWIN_MAXPATHLEN]byte
 	_ = fcntl(int(fd), F_GETPATH, int(uintptr(&buf[0]))) or_return
 	return strings.clone_from_cstring(cstring(&buf[0]))
 }
 
+@(require_results)
 absolute_path_from_relative :: proc(rel: string) -> (path: string, err: Error) {
 	rel := rel
 	if rel == "" {
@@ -1031,6 +1044,7 @@ flush :: proc(fd: Handle) -> Error {
 	return cast(Platform_Error)_unix_fsync(fd)
 }
 
+@(require_results)
 lookup_env :: proc(key: string, allocator := context.allocator) -> (value: string, found: bool) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == allocator)
 	path_str := strings.clone_to_cstring(key, context.temp_allocator)
@@ -1041,6 +1055,7 @@ lookup_env :: proc(key: string, allocator := context.allocator) -> (value: strin
 	return strings.clone(string(cstr), allocator), true
 }
 
+@(require_results)
 get_env :: proc(key: string, allocator := context.allocator) -> (value: string) {
 	value, _ = lookup_env(key, allocator)
 	return
@@ -1067,6 +1082,7 @@ unset_env :: proc(key: string) -> Error {
 	return nil
 }
 
+@(require_results)
 get_current_directory :: proc() -> string {
 	page_size := get_page_size() // NOTE(tetra): See note in os_linux.odin/get_current_directory.
 	buf := make([dynamic]u8, page_size)
@@ -1109,6 +1125,7 @@ exit :: proc "contextless" (code: int) -> ! {
 	_unix_exit(i32(code))
 }
 
+@(require_results)
 current_thread_id :: proc "contextless" () -> int {
 	tid: u64
 	// NOTE(Oskar): available from OSX 10.6 and iOS 3.2.
@@ -1119,12 +1136,14 @@ current_thread_id :: proc "contextless" () -> int {
 	return int(tid)
 }
 
+@(require_results)
 dlopen :: proc(filename: string, flags: int) -> rawptr {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(filename, context.temp_allocator)
 	handle := _unix_dlopen(cstr, flags)
 	return handle
 }
+@(require_results)
 dlsym :: proc(handle: rawptr, symbol: string) -> rawptr {
 	assert(handle != nil)
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
@@ -1140,6 +1159,7 @@ dlerror :: proc() -> string {
 	return string(_unix_dlerror())
 }
 
+@(require_results)
 get_page_size :: proc() -> int {
 	// NOTE(tetra): The page size never changes, so why do anything complicated
 	// if we don't have to.
@@ -1152,7 +1172,7 @@ get_page_size :: proc() -> int {
 	return page_size
 }
 
-@(private)
+@(private, require_results)
 _processor_core_count :: proc() -> int {
 	count : int = 0
 	count_size := size_of(count)
@@ -1165,6 +1185,7 @@ _processor_core_count :: proc() -> int {
 	return 1
 }
 
+@(require_results)
 _alloc_command_line_arguments :: proc() -> []string {
 	res := make([]string, len(runtime.args__))
 	for _, i in res {
@@ -1173,6 +1194,7 @@ _alloc_command_line_arguments :: proc() -> []string {
 	return res
 }
 
+@(require_results)
 socket :: proc(domain: int, type: int, protocol: int) -> (Socket, Error) {
 	result := _unix_socket(domain, type, protocol)
 	if result < 0 {
@@ -1181,7 +1203,8 @@ socket :: proc(domain: int, type: int, protocol: int) -> (Socket, Error) {
 	return Socket(result), nil
 }
 
-connect :: proc(sd: Socket, addr: ^SOCKADDR, len: socklen_t) -> (Error) {
+@(require_results)
+connect :: proc(sd: Socket, addr: ^SOCKADDR, len: socklen_t) -> Error {
 	result := _unix_connect(int(sd), addr, len)
 	if result < 0 {
 		return get_last_error()
@@ -1189,7 +1212,7 @@ connect :: proc(sd: Socket, addr: ^SOCKADDR, len: socklen_t) -> (Error) {
 	return nil
 }
 
-bind :: proc(sd: Socket, addr: ^SOCKADDR, len: socklen_t) -> (Error) {
+bind :: proc(sd: Socket, addr: ^SOCKADDR, len: socklen_t) -> Error {
 	result := _unix_bind(int(sd), addr, len)
 	if result < 0 {
 		return get_last_error()
@@ -1205,7 +1228,7 @@ accept :: proc(sd: Socket, addr: ^SOCKADDR, len: rawptr) -> (Socket, Error) {
 	return Socket(result), nil
 }
 
-listen :: proc(sd: Socket, backlog: int) -> (Error) {
+listen :: proc(sd: Socket, backlog: int) -> Error {
 	result := _unix_listen(int(sd), backlog)
 	if result < 0 {
 		return get_last_error()
@@ -1213,7 +1236,7 @@ listen :: proc(sd: Socket, backlog: int) -> (Error) {
 	return nil
 }
 
-setsockopt :: proc(sd: Socket, level: int, optname: int, optval: rawptr, optlen: socklen_t) -> (Error) {
+setsockopt :: proc(sd: Socket, level: int, optname: int, optval: rawptr, optlen: socklen_t) -> Error {
 	result := _unix_setsockopt(int(sd), level, optname, optval, optlen)
 	if result < 0 {
 		return get_last_error()
@@ -1261,7 +1284,7 @@ send :: proc(sd: Socket, data: []byte, flags: int) -> (u32, Error) {
 	return u32(result), nil
 }
 
-shutdown :: proc(sd: Socket, how: int) -> (Error) {
+shutdown :: proc(sd: Socket, how: int) -> Error {
 	result := _unix_shutdown(int(sd), how)
 	if result < 0 {
 		return get_last_error()

core/os/os_freebsd.odin

@@ -353,13 +353,13 @@ S_ISGID :: 0o2000 // Set group id on execution
 S_ISVTX :: 0o1000 // Directory restrcted delete
 
 
-S_ISLNK  :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFLNK  }
+@(require_results) S_ISLNK  :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFLNK  }
-S_ISREG  :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFREG  }
+@(require_results) S_ISREG  :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFREG  }
-S_ISDIR  :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFDIR  }
+@(require_results) S_ISDIR  :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFDIR  }
-S_ISCHR  :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFCHR  }
+@(require_results) S_ISCHR  :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFCHR  }
-S_ISBLK  :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFBLK  }
+@(require_results) S_ISBLK  :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFBLK  }
-S_ISFIFO :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFIFO  }
+@(require_results) S_ISFIFO :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFIFO  }
-S_ISSOCK :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFSOCK }
+@(require_results) S_ISSOCK :: #force_inline proc(m: mode_t) -> bool { return (m & S_IFMT) == S_IFSOCK }
 
 F_OK :: 0 // Test for file existance
 X_OK :: 1 // Test for execute permission
@@ -415,6 +415,7 @@ foreign dl {
 	@(link_name="pthread_getthreadid_np") pthread_getthreadid_np :: proc() -> c.int ---
 }
 
+@(require_results)
 is_path_separator :: proc(r: rune) -> bool {
 	return r == '/'
 }
@@ -424,6 +425,7 @@ get_last_error :: proc "contextless" () -> Error {
 	return Platform_Error(__Error_location()^)
 }
 
+@(require_results)
 open :: proc(path: string, flags: int = O_RDONLY, mode: int = 0) -> (Handle, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -505,6 +507,7 @@ seek :: proc(fd: Handle, offset: i64, whence: int) -> (i64, Error) {
 	return res, nil
 }
 
+@(require_results)
 file_size :: proc(fd: Handle) -> (size: i64, err: Error) {
 	size = -1
 	s := _fstat(fd) or_return
@@ -553,6 +556,7 @@ remove_directory :: proc(path: string) -> Error {
 	return nil
 }
 
+@(require_results)
 is_file_handle :: proc(fd: Handle) -> bool {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -561,6 +565,7 @@ is_file_handle :: proc(fd: Handle) -> bool {
 	return S_ISREG(s.mode)
 }
 
+@(require_results)
 is_file_path :: proc(path: string, follow_links: bool = true) -> bool {
 	s: OS_Stat
 	err: Error
@@ -575,6 +580,7 @@ is_file_path :: proc(path: string, follow_links: bool = true) -> bool {
 	return S_ISREG(s.mode)
 }
 
+@(require_results)
 is_dir_handle :: proc(fd: Handle) -> bool {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -583,6 +589,7 @@ is_dir_handle :: proc(fd: Handle) -> bool {
 	return S_ISDIR(s.mode)
 }
 
+@(require_results)
 is_dir_path :: proc(path: string, follow_links: bool = true) -> bool {
 	s: OS_Stat
 	err: Error
@@ -610,6 +617,7 @@ stderr: Handle = 2
 last_write_time :: proc(fd: Handle) -> File_Time {}                                                                  
 last_write_time_by_name :: proc(name: string) -> File_Time {}                                                        
 */
+@(require_results)
 last_write_time :: proc(fd: Handle) -> (File_Time, Error) {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -619,6 +627,7 @@ last_write_time :: proc(fd: Handle) -> (File_Time, Error) {
 	return File_Time(modified), nil
 }
 
+@(require_results)
 last_write_time_by_name :: proc(name: string) -> (File_Time, Error) {
 	s, err := _stat(name)
 	if err != nil {
@@ -628,7 +637,7 @@ last_write_time_by_name :: proc(name: string) -> (File_Time, Error) {
 	return File_Time(modified), nil
 }
 
-@private
+@(private, require_results)
 _stat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -640,7 +649,7 @@ _stat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -654,7 +663,7 @@ _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	s: OS_Stat = ---
 	result := _unix_fstat(fd, &s)
@@ -664,7 +673,7 @@ _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	dirp := _unix_fdopendir(fd)
 	if dirp == cast(Dir)nil {
@@ -673,7 +682,7 @@ _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	return dirp, nil
 }
 
-@private
+@(private)
 _closedir :: proc(dirp: Dir) -> Error {
 	rc := _unix_closedir(dirp)
 	if rc != 0 {
@@ -682,12 +691,12 @@ _closedir :: proc(dirp: Dir) -> Error {
 	return nil
 }
 
-@private
+@(private)
 _rewinddir :: proc(dirp: Dir) {
 	_unix_rewinddir(dirp)
 }
 
-@private
+@(private, require_results)
 _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool) {
 	result: ^Dirent
 	rc := _unix_readdir_r(dirp, &entry, &result)
@@ -705,7 +714,7 @@ _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool)
 	return
 }
 
-@private
+@(private, require_results)
 _readlink :: proc(path: string) -> (string, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == context.allocator)
 
@@ -730,6 +739,7 @@ _readlink :: proc(path: string) -> (string, Error) {
 	return "", Error{}
 }
 
+@(require_results)
 absolute_path_from_handle :: proc(fd: Handle) -> (string, Error) {
 	// NOTE(Feoramund): The situation isn't ideal, but this was the best way I
 	// could find to implement this. There are a couple outstanding bug reports
@@ -752,6 +762,7 @@ absolute_path_from_handle :: proc(fd: Handle) -> (string, Error) {
 	return path, nil
 }
 
+@(require_results)
 absolute_path_from_relative :: proc(rel: string) -> (path: string, err: Error) {
 	rel := rel
 	if rel == "" {
@@ -784,6 +795,7 @@ access :: proc(path: string, mask: int) -> (bool, Error) {
 	return true, nil
 }
 
+@(require_results)
 lookup_env :: proc(key: string, allocator := context.allocator) -> (value: string, found: bool) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == allocator)
 
@@ -795,11 +807,13 @@ lookup_env :: proc(key: string, allocator := context.allocator) -> (value: strin
 	return strings.clone(string(cstr), allocator), true
 }
 
+@(require_results)
 get_env :: proc(key: string, allocator := context.allocator) -> (value: string) {
 	value, _ = lookup_env(key, allocator)
 	return
 }
 
+@(require_results)
 get_current_directory :: proc() -> string {
 	// NOTE(tetra): I would use PATH_MAX here, but I was not able to find
 	// an authoritative value for it across all systems.
@@ -835,16 +849,19 @@ exit :: proc "contextless" (code: int) -> ! {
 	_unix_exit(c.int(code))
 }
 
+@(require_results)
 current_thread_id :: proc "contextless" () -> int {
 	return cast(int) pthread_getthreadid_np()
 }
 
+@(require_results)
 dlopen :: proc(filename: string, flags: int) -> rawptr {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(filename, context.temp_allocator)
 	handle := _unix_dlopen(cstr, c.int(flags))
 	return handle
 }
+@(require_results)
 dlsym :: proc(handle: rawptr, symbol: string) -> rawptr {
 	assert(handle != nil)
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
@@ -860,6 +877,7 @@ dlerror :: proc() -> string {
 	return string(_unix_dlerror())
 }
 
+@(require_results)
 get_page_size :: proc() -> int {
 	// NOTE(tetra): The page size never changes, so why do anything complicated
 	// if we don't have to.
@@ -872,7 +890,7 @@ get_page_size :: proc() -> int {
 	return page_size
 }
 
-@(private)
+@(private, require_results)
 _processor_core_count :: proc() -> int {
 	count : int = 0
 	count_size := size_of(count)
@@ -886,6 +904,7 @@ _processor_core_count :: proc() -> int {
 }
 
 
+@(require_results)
 _alloc_command_line_arguments :: proc() -> []string {
 	res := make([]string, len(runtime.args__))
 	for arg, i in runtime.args__ {

core/os/os_haiku.odin

@@ -177,6 +177,7 @@ Dirent :: struct {
 
 Dir :: distinct rawptr // DIR*
 
+@(require_results)
 is_path_separator :: proc(r: rune) -> bool {
 	return r == '/'
 }
@@ -186,6 +187,7 @@ get_last_error :: proc "contextless" () -> Error {
 	return Platform_Error(__error()^)
 }
 
+@(require_results)
 fork :: proc() -> (Pid, Error) {
 	pid := _unix_fork()
 	if pid == -1 {
@@ -194,6 +196,7 @@ fork :: proc() -> (Pid, Error) {
 	return Pid(pid), nil
 }
 
+@(require_results)
 open :: proc(path: string, flags: int = O_RDONLY, mode: int = 0) -> (Handle, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -274,6 +277,7 @@ seek :: proc(fd: Handle, offset: i64, whence: int) -> (i64, Error) {
 	return res, nil
 }
 
+@(require_results)
 file_size :: proc(fd: Handle) -> (i64, Error) {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -285,6 +289,7 @@ file_size :: proc(fd: Handle) -> (i64, Error) {
 // "Argv" arguments converted to Odin strings
 args := _alloc_command_line_arguments()
 
+@(require_results)
 _alloc_command_line_arguments :: proc() -> []string {
 	res := make([]string, len(runtime.args__))
 	for arg, i in runtime.args__ {
@@ -293,7 +298,7 @@ _alloc_command_line_arguments :: proc() -> []string {
 	return res
 }
 
-@private
+@(private, require_results)
 _stat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -307,7 +312,7 @@ _stat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -321,7 +326,7 @@ _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	// deliberately uninitialized
 	s: OS_Stat = ---
@@ -332,7 +337,7 @@ _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private)
 _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	dirp := _unix_fdopendir(fd)
 	if dirp == cast(Dir)nil {
@@ -341,7 +346,7 @@ _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	return dirp, nil
 }
 
-@private
+@(private)
 _closedir :: proc(dirp: Dir) -> Error {
 	rc := _unix_closedir(dirp)
 	if rc != 0 {
@@ -350,12 +355,12 @@ _closedir :: proc(dirp: Dir) -> Error {
 	return nil
 }
 
-@private
+@(private)
 _rewinddir :: proc(dirp: Dir) {
 	_unix_rewinddir(dirp)
 }
 
-@private
+@(private, require_results)
 _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool) {
 	result: ^Dirent
 	rc := _unix_readdir_r(dirp, &entry, &result)
@@ -373,7 +378,7 @@ _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool)
 	return
 }
 
-@private
+@(private, require_results)
 _readlink :: proc(path: string) -> (string, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == context.allocator)
 	path_cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -395,10 +400,12 @@ _readlink :: proc(path: string) -> (string, Error) {
 	}
 }
 
+@(require_results)
 absolute_path_from_handle :: proc(fd: Handle) -> (string, Error) {
 	return "", Error(ENOSYS)
 }
 
+@(require_results)
 absolute_path_from_relative :: proc(rel: string) -> (path: string, err: Error) {
 	rel := rel
 	if rel == "" {
@@ -430,6 +437,7 @@ access :: proc(path: string, mask: int) -> (bool, Error) {
 	return true, nil
 }
 
+@(require_results)
 lookup_env :: proc(key: string, allocator := context.allocator) -> (value: string, found: bool) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == allocator)
 	path_str := strings.clone_to_cstring(key, context.temp_allocator)
@@ -440,12 +448,13 @@ lookup_env :: proc(key: string, allocator := context.allocator) -> (value: strin
 	return strings.clone(string(cstr), allocator), true
 }
 
+@(require_results)
 get_env :: proc(key: string, allocator := context.allocator) -> (value: string) {
 	value, _ = lookup_env(key, allocator)
 	return
 }
 
-@(private)
+@(private, require_results)
 _processor_core_count :: proc() -> int {
 	info: haiku.system_info
 	haiku.get_system_info(&info)

core/os/os_js.odin

@@ -3,10 +3,12 @@ package os
 
 import "base:runtime"
 
+@(require_results)
 is_path_separator :: proc(c: byte) -> bool {
 	return c == '/' || c == '\\'
 }
 
+@(require_results)
 open :: proc(path: string, mode: int = O_RDONLY, perm: int = 0) -> (Handle, Error) {
 	unimplemented("core:os procedure not supported on JS target")
 }
@@ -38,6 +40,7 @@ seek :: proc(fd: Handle, offset: i64, whence: int) -> (i64, Error) {
 	unimplemented("core:os procedure not supported on JS target")
 }
 
+@(require_results)
 file_size :: proc(fd: Handle) -> (i64, Error) {
 	unimplemented("core:os procedure not supported on JS target")
 }
@@ -65,20 +68,24 @@ write_at :: proc(fd: Handle, data: []byte, offset: i64) -> (n: int, err: Error)
 stdout: Handle = 1
 stderr: Handle = 2
 
+@(require_results)
 get_std_handle :: proc "contextless" (h: uint) -> Handle {
 	context = runtime.default_context()
 	unimplemented("core:os procedure not supported on JS target")
 }
 
 
+@(require_results)
 exists :: proc(path: string) -> bool {
 	unimplemented("core:os procedure not supported on JS target")
 }
 
+@(require_results)
 is_file :: proc(path: string) -> bool {
 	unimplemented("core:os procedure not supported on JS target")
 }
 
+@(require_results)
 is_dir :: proc(path: string) -> bool {
 	unimplemented("core:os procedure not supported on JS target")
 }
@@ -86,6 +93,7 @@ is_dir :: proc(path: string) -> bool {
 // NOTE(tetra): GetCurrentDirectory is not thread safe with SetCurrentDirectory and GetFullPathName
 //@private cwd_lock := win32.SRWLOCK{} // zero is initialized
 
+@(require_results)
 get_current_directory :: proc(allocator := context.allocator) -> string {
 	unimplemented("core:os procedure not supported on JS target")
 }
@@ -111,12 +119,12 @@ remove_directory :: proc(path: string) -> (err: Error) {
 
 
 
-@(private)
+@(private, require_results)
 is_abs :: proc(path: string) -> bool {
 	unimplemented("core:os procedure not supported on JS target")
 }
 
-@(private)
+@(private, require_results)
 fix_long_path :: proc(path: string) -> string {
 	unimplemented("core:os procedure not supported on JS target")
 }
@@ -151,10 +159,12 @@ remove :: proc(name: string) -> Error {
 }
 
 
+@(require_results)
 pipe :: proc() -> (r, w: Handle, err: Error) {
 	unimplemented("core:os procedure not supported on JS target")
 }
 
+@(require_results)
 read_dir :: proc(fd: Handle, n: int, allocator := context.allocator) -> (fi: []File_Info, err: Error) {
 	unimplemented("core:os procedure not supported on JS target")
 }
@@ -251,20 +261,23 @@ args := _alloc_command_line_arguments()
 
 
 
+@(require_results)
 last_write_time :: proc(fd: Handle) -> (File_Time, Error) {
 	unimplemented("core:os procedure not supported on JS target")
 }
 
+@(require_results)
 last_write_time_by_name :: proc(name: string) -> (File_Time, Error) {
 	unimplemented("core:os procedure not supported on JS target")
 }
 
 
+@(require_results)
 get_page_size :: proc() -> int {
 	unimplemented("core:os procedure not supported on JS target")
 }
 
-@(private)
+@(private, require_results)
 _processor_core_count :: proc() -> int {
 	unimplemented("core:os procedure not supported on JS target")
 }
@@ -276,6 +289,7 @@ exit :: proc "contextless" (code: int) -> ! {
 
 
 
+@(require_results)
 current_thread_id :: proc "contextless" () -> int {
 	context = runtime.default_context()
 	unimplemented("core:os procedure not supported on JS target")
@@ -283,6 +297,7 @@ current_thread_id :: proc "contextless" () -> int {
 
 
 
+@(require_results)
 _alloc_command_line_arguments :: proc() -> []string {
 	return nil
 }

core/os/os_linux.odin

@@ -448,13 +448,13 @@ S_ISGID :: 0o2000 // Set group id on execution
 S_ISVTX :: 0o1000 // Directory restrcted delete
 
 
-S_ISLNK  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFLNK  }
+@(require_results) S_ISLNK  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFLNK  }
-S_ISREG  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFREG  }
+@(require_results) S_ISREG  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFREG  }
-S_ISDIR  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFDIR  }
+@(require_results) S_ISDIR  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFDIR  }
-S_ISCHR  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFCHR  }
+@(require_results) S_ISCHR  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFCHR  }
-S_ISBLK  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFBLK  }
+@(require_results) S_ISBLK  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFBLK  }
-S_ISFIFO :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFIFO  }
+@(require_results) S_ISFIFO :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFIFO  }
-S_ISSOCK :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFSOCK }
+@(require_results) S_ISSOCK :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFSOCK }
 
 F_OK :: 0 // Test for file existance
 X_OK :: 1 // Test for execute permission
@@ -506,12 +506,13 @@ foreign dl {
 	@(link_name="freeifaddrs")      _freeifaddrs        :: proc(ifa: ^ifaddrs) ---
 }
 
+@(require_results)
 is_path_separator :: proc(r: rune) -> bool {
 	return r == '/'
 }
 
 // determine errno from syscall return value
-@private
+@(private, require_results)
 _get_errno :: proc(res: int) -> Error {
 	if res < 0 && res > -4096 {
 		return Platform_Error(-res)
@@ -536,7 +537,7 @@ get_last_error :: proc "contextless" () -> Error {
 	return err
 }
 
-personality :: proc(persona: u64) -> (Error) {
+personality :: proc(persona: u64) -> Error {
 	res := unix.sys_personality(persona)
 	if res == -1 {
 		return _get_errno(res)
@@ -544,6 +545,7 @@ personality :: proc(persona: u64) -> (Error) {
 	return nil
 }
 
+@(require_results)
 fork :: proc() -> (Pid, Error) {
 	pid := unix.sys_fork()
 	if pid == -1 {
@@ -567,6 +569,7 @@ execvp :: proc(path: string, args: []string) -> Error {
 }
 
 
+@(require_results)
 open :: proc(path: string, flags: int = O_RDONLY, mode: int = 0o000) -> (Handle, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -659,6 +662,7 @@ seek :: proc(fd: Handle, offset: i64, whence: int) -> (i64, Error) {
 	return i64(res), nil
 }
 
+@(require_results)
 file_size :: proc(fd: Handle) -> (i64, Error) {
 	// deliberately uninitialized; the syscall fills this buffer for us
 	s: OS_Stat = ---
@@ -694,6 +698,7 @@ remove_directory :: proc(path: string) -> Error {
 	return _get_errno(unix.sys_rmdir(path_cstr))
 }
 
+@(require_results)
 is_file_handle :: proc(fd: Handle) -> bool {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -702,6 +707,7 @@ is_file_handle :: proc(fd: Handle) -> bool {
 	return S_ISREG(s.mode)
 }
 
+@(require_results)
 is_file_path :: proc(path: string, follow_links: bool = true) -> bool {
 	s: OS_Stat
 	err: Error
@@ -717,6 +723,7 @@ is_file_path :: proc(path: string, follow_links: bool = true) -> bool {
 }
 
 
+@(require_results)
 is_dir_handle :: proc(fd: Handle) -> bool {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -725,6 +732,7 @@ is_dir_handle :: proc(fd: Handle) -> bool {
 	return S_ISDIR(s.mode)
 }
 
+@(require_results)
 is_dir_path :: proc(path: string, follow_links: bool = true) -> bool {
 	s: OS_Stat
 	err: Error
@@ -742,6 +750,7 @@ is_dir_path :: proc(path: string, follow_links: bool = true) -> bool {
 is_file :: proc {is_file_path, is_file_handle}
 is_dir :: proc {is_dir_path, is_dir_handle}
 
+@(require_results)
 exists :: proc(path: string) -> bool {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cpath := strings.clone_to_cstring(path, context.temp_allocator)
@@ -759,19 +768,21 @@ stderr: Handle = 2
 last_write_time :: proc(fd: Handle) -> File_Time {}
 last_write_time_by_name :: proc(name: string) -> File_Time {}
 */
+@(require_results)
 last_write_time :: proc(fd: Handle) -> (time: File_Time, err: Error) {
 	s := _fstat(fd) or_return
 	modified := s.modified.seconds * 1_000_000_000 + s.modified.nanoseconds
 	return File_Time(modified), nil
 }
 
+@(require_results)
 last_write_time_by_name :: proc(name: string) -> (time: File_Time, err: Error) {
 	s := _stat(name) or_return
 	modified := s.modified.seconds * 1_000_000_000 + s.modified.nanoseconds
 	return File_Time(modified), nil
 }
 
-@private
+@(private, require_results)
 _stat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -785,7 +796,7 @@ _stat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -799,7 +810,7 @@ _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	// deliberately uninitialized; the syscall fills this buffer for us
 	s: OS_Stat = ---
@@ -810,7 +821,7 @@ _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	dirp := _unix_fdopendir(fd)
 	if dirp == cast(Dir)nil {
@@ -819,7 +830,7 @@ _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	return dirp, nil
 }
 
-@private
+@(private)
 _closedir :: proc(dirp: Dir) -> Error {
 	rc := _unix_closedir(dirp)
 	if rc != 0 {
@@ -828,12 +839,12 @@ _closedir :: proc(dirp: Dir) -> Error {
 	return nil
 }
 
-@private
+@(private)
 _rewinddir :: proc(dirp: Dir) {
 	_unix_rewinddir(dirp)
 }
 
-@private
+@(private, require_results)
 _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool) {
 	result: ^Dirent
 	rc := _unix_readdir_r(dirp, &entry, &result)
@@ -853,7 +864,7 @@ _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool)
 	return
 }
 
-@private
+@(private, require_results)
 _readlink :: proc(path: string) -> (string, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == context.allocator)
 	path_cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -876,6 +887,7 @@ _readlink :: proc(path: string) -> (string, Error) {
 	}
 }
 
+@(require_results)
 absolute_path_from_handle :: proc(fd: Handle) -> (string, Error) {
 	buf : [256]byte
 	fd_str := strconv.itoa( buf[:], cast(int)fd )
@@ -886,6 +898,7 @@ absolute_path_from_handle :: proc(fd: Handle) -> (string, Error) {
 	return _readlink(procfs_path)
 }
 
+@(require_results)
 absolute_path_from_relative :: proc(rel: string) -> (path: string, err: Error) {
 	rel := rel
 	if rel == "" {
@@ -916,6 +929,7 @@ access :: proc(path: string, mask: int) -> (bool, Error) {
 	return true, nil
 }
 
+@(require_results)
 lookup_env :: proc(key: string, allocator := context.allocator) -> (value: string, found: bool) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == allocator)
 	path_str := strings.clone_to_cstring(key, context.temp_allocator)
@@ -927,6 +941,7 @@ lookup_env :: proc(key: string, allocator := context.allocator) -> (value: strin
 	return strings.clone(string(cstr), allocator), true
 }
 
+@(require_results)
 get_env :: proc(key: string, allocator := context.allocator) -> (value: string) {
 	value, _ = lookup_env(key, allocator)
 	return
@@ -954,6 +969,7 @@ unset_env :: proc(key: string) -> Error {
 	return nil
 }
 
+@(require_results)
 get_current_directory :: proc() -> string {
 	// NOTE(tetra): I would use PATH_MAX here, but I was not able to find
 	// an authoritative value for it across all systems.
@@ -990,16 +1006,19 @@ exit :: proc "contextless" (code: int) -> ! {
 	_unix_exit(c.int(code))
 }
 
+@(require_results)
 current_thread_id :: proc "contextless" () -> int {
 	return unix.sys_gettid()
 }
 
+@(require_results)
 dlopen :: proc(filename: string, flags: int) -> rawptr {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(filename, context.temp_allocator)
 	handle := _unix_dlopen(cstr, c.int(flags))
 	return handle
 }
+@(require_results)
 dlsym :: proc(handle: rawptr, symbol: string) -> rawptr {
 	assert(handle != nil)
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
@@ -1015,6 +1034,7 @@ dlerror :: proc() -> string {
 	return string(_unix_dlerror())
 }
 
+@(require_results)
 get_page_size :: proc() -> int {
 	// NOTE(tetra): The page size never changes, so why do anything complicated
 	// if we don't have to.
@@ -1027,11 +1047,12 @@ get_page_size :: proc() -> int {
 	return page_size
 }
 
-@(private)
+@(private, require_results)
 _processor_core_count :: proc() -> int {
 	return int(_unix_get_nprocs())
 }
 
+@(require_results)
 _alloc_command_line_arguments :: proc() -> []string {
 	res := make([]string, len(runtime.args__))
 	for arg, i in runtime.args__ {
@@ -1040,6 +1061,7 @@ _alloc_command_line_arguments :: proc() -> []string {
 	return res
 }
 
+@(require_results)
 socket :: proc(domain: int, type: int, protocol: int) -> (Socket, Error) {
 	result := unix.sys_socket(domain, type, protocol)
 	if result < 0 {
@@ -1048,7 +1070,7 @@ socket :: proc(domain: int, type: int, protocol: int) -> (Socket, Error) {
 	return Socket(result), nil
 }
 
-bind :: proc(sd: Socket, addr: ^SOCKADDR, len: socklen_t) -> (Error) {
+bind :: proc(sd: Socket, addr: ^SOCKADDR, len: socklen_t) -> Error {
 	result := unix.sys_bind(int(sd), addr, len)
 	if result < 0 {
 		return _get_errno(result)
@@ -1057,7 +1079,7 @@ bind :: proc(sd: Socket, addr: ^SOCKADDR, len: socklen_t) -> (Error) {
 }
 
 
-connect :: proc(sd: Socket, addr: ^SOCKADDR, len: socklen_t) -> (Error) {
+connect :: proc(sd: Socket, addr: ^SOCKADDR, len: socklen_t) -> Error {
 	result := unix.sys_connect(int(sd), addr, len)
 	if result < 0 {
 		return _get_errno(result)
@@ -1073,7 +1095,7 @@ accept :: proc(sd: Socket, addr: ^SOCKADDR, len: rawptr) -> (Socket, Error) {
 	return Socket(result), nil
 }
 
-listen :: proc(sd: Socket, backlog: int) -> (Error) {
+listen :: proc(sd: Socket, backlog: int) -> Error {
 	result := unix.sys_listen(int(sd), backlog)
 	if result < 0 {
 		return _get_errno(result)
@@ -1081,7 +1103,7 @@ listen :: proc(sd: Socket, backlog: int) -> (Error) {
 	return nil
 }
 
-setsockopt :: proc(sd: Socket, level: int, optname: int, optval: rawptr, optlen: socklen_t) -> (Error) {
+setsockopt :: proc(sd: Socket, level: int, optname: int, optval: rawptr, optlen: socklen_t) -> Error {
 	result := unix.sys_setsockopt(int(sd), level, optname, optval, optlen)
 	if result < 0 {
 		return _get_errno(result)
@@ -1123,7 +1145,7 @@ send :: proc(sd: Socket, data: []byte, flags: int) -> (u32, Error) {
 	return u32(result), nil
 }
 
-shutdown :: proc(sd: Socket, how: int) -> (Error) {
+shutdown :: proc(sd: Socket, how: int) -> Error {
 	result := unix.sys_shutdown(int(sd), how)
 	if result < 0 {
 		return _get_errno(result)
@@ -1139,6 +1161,7 @@ fcntl :: proc(fd: int, cmd: int, arg: int) -> (int, Error) {
 	return result, nil
 }
 
+@(require_results)
 poll :: proc(fds: []pollfd, timeout: int) -> (int, Error) {
 	result := unix.sys_poll(raw_data(fds), uint(len(fds)), timeout)
 	if result < 0 {
@@ -1147,6 +1170,7 @@ poll :: proc(fds: []pollfd, timeout: int) -> (int, Error) {
 	return result, nil
 }
 
+@(require_results)
 ppoll :: proc(fds: []pollfd, timeout: ^unix.timespec, sigmask: ^sigset_t) -> (int, Error) {
 	result := unix.sys_ppoll(raw_data(fds), uint(len(fds)), timeout, sigmask, size_of(sigset_t))
 	if result < 0 {

core/os/os_netbsd.odin

@@ -407,13 +407,13 @@ S_ISUID :: 0o4000 // Set user id on execution
 S_ISGID :: 0o2000 // Set group id on execution
 S_ISVTX :: 0o1000 // Directory restrcted delete
 
-S_ISLNK  :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFLNK  }
+@(require_results) S_ISLNK  :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFLNK  }
-S_ISREG  :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFREG  }
+@(require_results) S_ISREG  :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFREG  }
-S_ISDIR  :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFDIR  }
+@(require_results) S_ISDIR  :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFDIR  }
-S_ISCHR  :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFCHR  }
+@(require_results) S_ISCHR  :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFCHR  }
-S_ISBLK  :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFBLK  }
+@(require_results) S_ISBLK  :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFBLK  }
-S_ISFIFO :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFIFO  }
+@(require_results) S_ISFIFO :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFIFO  }
-S_ISSOCK :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFSOCK }
+@(require_results) S_ISSOCK :: #force_inline proc "contextless" (m: mode_t) -> bool { return (m & S_IFMT) == S_IFSOCK }
 
 F_OK :: 0 // Test for file existance
 X_OK :: 1 // Test for execute permission
@@ -561,6 +561,7 @@ seek :: proc(fd: Handle, offset: i64, whence: int) -> (i64, Error) {
 	return res, nil
 }
 
+@(require_results)
 file_size :: proc(fd: Handle) -> (size: i64, err: Error) {
 	size = -1
 	s := _fstat(fd) or_return
@@ -609,6 +610,7 @@ remove_directory :: proc(path: string) -> Error {
 	return nil
 }
 
+@(require_results)
 is_file_handle :: proc(fd: Handle) -> bool {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -617,6 +619,7 @@ is_file_handle :: proc(fd: Handle) -> bool {
 	return S_ISREG(s.mode)
 }
 
+@(require_results)
 is_file_path :: proc(path: string, follow_links: bool = true) -> bool {
 	s: OS_Stat
 	err: Error
@@ -631,6 +634,7 @@ is_file_path :: proc(path: string, follow_links: bool = true) -> bool {
 	return S_ISREG(s.mode)
 }
 
+@(require_results)
 is_dir_handle :: proc(fd: Handle) -> bool {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -639,6 +643,7 @@ is_dir_handle :: proc(fd: Handle) -> bool {
 	return S_ISDIR(s.mode)
 }
 
+@(require_results)
 is_dir_path :: proc(path: string, follow_links: bool = true) -> bool {
 	s: OS_Stat
 	err: Error
@@ -656,6 +661,7 @@ is_dir_path :: proc(path: string, follow_links: bool = true) -> bool {
 is_file :: proc {is_file_path, is_file_handle}
 is_dir :: proc {is_dir_path, is_dir_handle}
 
+@(require_results)
 exists :: proc(path: string) -> bool {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cpath := strings.clone_to_cstring(path, context.temp_allocator)
@@ -663,6 +669,7 @@ exists :: proc(path: string) -> bool {
 	return res == 0
 }
 
+@(require_results)
 fcntl :: proc(fd: int, cmd: int, arg: int) -> (int, Error) {
 	result := _unix_fcntl(Handle(fd), c.int(cmd), uintptr(arg))
 	if result < 0 {
@@ -677,19 +684,21 @@ stdin: Handle  = 0
 stdout: Handle = 1
 stderr: Handle = 2
 
+@(require_results)
 last_write_time :: proc(fd: Handle) -> (time: File_Time, err: Error) {
 	s := _fstat(fd) or_return
 	modified := s.modified.seconds * 1_000_000_000 + s.modified.nanoseconds
 	return File_Time(modified), nil
 }
 
+@(require_results)
 last_write_time_by_name :: proc(name: string) -> (time: File_Time, err: Error) {
 	s := _stat(name) or_return
 	modified := s.modified.seconds * 1_000_000_000 + s.modified.nanoseconds
 	return File_Time(modified), nil
 }
 
-@private
+@(private, require_results)
 _stat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -701,7 +710,7 @@ _stat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -715,7 +724,7 @@ _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	s: OS_Stat = ---
 	result := _unix_fstat(fd, &s)
@@ -725,7 +734,7 @@ _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	dirp := _unix_fdopendir(fd)
 	if dirp == cast(Dir)nil {
@@ -734,7 +743,7 @@ _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	return dirp, nil
 }
 
-@private
+@(private)
 _closedir :: proc(dirp: Dir) -> Error {
 	rc := _unix_closedir(dirp)
 	if rc != 0 {
@@ -743,12 +752,12 @@ _closedir :: proc(dirp: Dir) -> Error {
 	return nil
 }
 
-@private
+@(private)
 _rewinddir :: proc(dirp: Dir) {
 	_unix_rewinddir(dirp)
 }
 
-@private
+@(private, require_results)
 _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool) {
 	result: ^Dirent
 	rc := _unix_readdir_r(dirp, &entry, &result)
@@ -767,7 +776,7 @@ _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool)
 	return
 }
 
-@private
+@(private, require_results)
 _readlink :: proc(path: string) -> (string, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == context.allocator)
 
@@ -792,12 +801,14 @@ _readlink :: proc(path: string) -> (string, Error) {
 	return "", Error{}
 }
 
+@(require_results)
 absolute_path_from_handle :: proc(fd: Handle) -> (path: string, err: Error) {
 	buf: [MAX_PATH]byte
 	_ = fcntl(int(fd), F_GETPATH, int(uintptr(&buf[0]))) or_return
 	return strings.clone_from_cstring(cstring(&buf[0]))
 }
 
+@(require_results)
 absolute_path_from_relative :: proc(rel: string) -> (path: string, err: Error) {
 	rel := rel
 	if rel == "" {
@@ -829,6 +840,7 @@ access :: proc(path: string, mask: int) -> (bool, Error) {
 	return true, nil
 }
 
+@(require_results)
 lookup_env :: proc(key: string, allocator := context.allocator) -> (value: string, found: bool) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == allocator)
 
@@ -840,11 +852,13 @@ lookup_env :: proc(key: string, allocator := context.allocator) -> (value: strin
 	return strings.clone(string(cstr), allocator), true
 }
 
+@(require_results)
 get_env :: proc(key: string, allocator := context.allocator) -> (value: string) {
 	value, _ = lookup_env(key, allocator)
 	return
 }
 
+@(require_results)
 get_current_directory :: proc() -> string {
 	// NOTE(tetra): I would use PATH_MAX here, but I was not able to find
 	// an authoritative value for it across all systems.
@@ -880,10 +894,12 @@ exit :: proc "contextless" (code: int) -> ! {
 	_unix_exit(c.int(code))
 }
 
+@(require_results)
 current_thread_id :: proc "contextless" () -> int {
 	return int(_lwp_self())
 }
 
+@(require_results)
 dlopen :: proc(filename: string, flags: int) -> rawptr {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(filename, context.temp_allocator)
@@ -891,6 +907,7 @@ dlopen :: proc(filename: string, flags: int) -> rawptr {
 	return handle
 }
 
+@(require_results)
 dlsym :: proc(handle: rawptr, symbol: string) -> rawptr {
 	assert(handle != nil)
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
@@ -904,10 +921,12 @@ dlclose :: proc(handle: rawptr) -> bool {
 	return _unix_dlclose(handle) == 0
 }
 
+@(require_results)
 dlerror :: proc() -> string {
 	return string(_unix_dlerror())
 }
 
+@(require_results)
 get_page_size :: proc() -> int {
 	// NOTE(tetra): The page size never changes, so why do anything complicated
 	// if we don't have to.
@@ -920,7 +939,7 @@ get_page_size :: proc() -> int {
 	return page_size
 }
 
-@(private)
+@(private, require_results)
 _processor_core_count :: proc() -> int {
 	count : int = 0
 	count_size := size_of(count)
@@ -933,6 +952,7 @@ _processor_core_count :: proc() -> int {
 	return 1
 }
 
+@(require_results)
 _alloc_command_line_arguments :: proc() -> []string {
 	res := make([]string, len(runtime.args__))
 	for arg, i in runtime.args__ {

core/os/os_openbsd.odin

@@ -322,13 +322,13 @@ S_ISUID :: 0o4000 // Set user id on execution
 S_ISGID :: 0o2000 // Set group id on execution
 S_ISTXT :: 0o1000 // Sticky bit
 
-S_ISLNK  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFLNK  }
+@(require_results) S_ISLNK  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFLNK  }
-S_ISREG  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFREG  }
+@(require_results) S_ISREG  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFREG  }
-S_ISDIR  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFDIR  }
+@(require_results) S_ISDIR  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFDIR  }
-S_ISCHR  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFCHR  }
+@(require_results) S_ISCHR  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFCHR  }
-S_ISBLK  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFBLK  }
+@(require_results) S_ISBLK  :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFBLK  }
-S_ISFIFO :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFIFO  }
+@(require_results) S_ISFIFO :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFIFO  }
-S_ISSOCK :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFSOCK }
+@(require_results) S_ISSOCK :: #force_inline proc(m: u32) -> bool { return (m & S_IFMT) == S_IFSOCK }
 
 F_OK :: 0x00 // Test for file existance
 X_OK :: 0x01 // Test for execute permission
@@ -489,6 +489,7 @@ seek :: proc(fd: Handle, offset: i64, whence: int) -> (i64, Error) {
 	return res, nil
 }
 
+@(require_results)
 file_size :: proc(fd: Handle) -> (size: i64, err: Error) {
 	size = -1
 	s :=  _fstat(fd) or_return
@@ -537,6 +538,7 @@ remove_directory :: proc(path: string) -> Error {
 	return nil
 }
 
+@(require_results)
 is_file_handle :: proc(fd: Handle) -> bool {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -545,6 +547,7 @@ is_file_handle :: proc(fd: Handle) -> bool {
 	return S_ISREG(s.mode)
 }
 
+@(require_results)
 is_file_path :: proc(path: string, follow_links: bool = true) -> bool {
 	s: OS_Stat
 	err: Error
@@ -559,6 +562,7 @@ is_file_path :: proc(path: string, follow_links: bool = true) -> bool {
 	return S_ISREG(s.mode)
 }
 
+@(require_results)
 is_dir_handle :: proc(fd: Handle) -> bool {
 	s, err := _fstat(fd)
 	if err != nil {
@@ -567,6 +571,7 @@ is_dir_handle :: proc(fd: Handle) -> bool {
 	return S_ISDIR(s.mode)
 }
 
+@(require_results)
 is_dir_path :: proc(path: string, follow_links: bool = true) -> bool {
 	s: OS_Stat
 	err: Error
@@ -594,19 +599,21 @@ stderr: Handle = 2
 last_write_time :: proc(fd: Handle) -> File_Time {}                                                               
 last_write_time_by_name :: proc(name: string) -> File_Time {}                                                     
 */
+@(require_results)
 last_write_time :: proc(fd: Handle) -> (time: File_Time, err: Error) {
 	s := _fstat(fd) or_return
 	modified := s.modified.seconds * 1_000_000_000 + s.modified.nanoseconds
 	return File_Time(modified), nil
 }
 
+@(require_results)
 last_write_time_by_name :: proc(name: string) -> (time: File_Time, err: Error) {
 	s := _stat(name) or_return
 	modified := s.modified.seconds * 1_000_000_000 + s.modified.nanoseconds
 	return File_Time(modified), nil
 }
 
-@private
+@(private, require_results)
 _stat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -620,7 +627,7 @@ _stat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -634,7 +641,7 @@ _lstat :: proc(path: string) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	// deliberately uninitialized
 	s: OS_Stat = ---
@@ -645,7 +652,7 @@ _fstat :: proc(fd: Handle) -> (OS_Stat, Error) {
 	return s, nil
 }
 
-@private
+@(private, require_results)
 _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	dirp := _unix_fdopendir(fd)
 	if dirp == cast(Dir)nil {
@@ -654,7 +661,7 @@ _fdopendir :: proc(fd: Handle) -> (Dir, Error) {
 	return dirp, nil
 }
 
-@private
+@(private)
 _closedir :: proc(dirp: Dir) -> Error {
 	rc := _unix_closedir(dirp)
 	if rc != 0 {
@@ -663,12 +670,12 @@ _closedir :: proc(dirp: Dir) -> Error {
 	return nil
 }
 
-@private
+@(private)
 _rewinddir :: proc(dirp: Dir) {
 	_unix_rewinddir(dirp)
 }
 
-@private
+@(private, require_results)
 _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool) {
 	result: ^Dirent
 	rc := _unix_readdir_r(dirp, &entry, &result)
@@ -687,7 +694,7 @@ _readdir :: proc(dirp: Dir) -> (entry: Dirent, err: Error, end_of_stream: bool)
 	return
 }
 
-@private
+@(private, require_results)
 _readlink :: proc(path: string) -> (string, Error) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == context.allocator)
 	path_cstr := strings.clone_to_cstring(path, context.temp_allocator)
@@ -710,10 +717,12 @@ _readlink :: proc(path: string) -> (string, Error) {
 }
 
 // XXX OpenBSD
+@(require_results)
 absolute_path_from_handle :: proc(fd: Handle) -> (string, Error) {
 	return "", Error(ENOSYS)
 }
 
+@(require_results)
 absolute_path_from_relative :: proc(rel: string) -> (path: string, err: Error) {
 	rel := rel
 	if rel == "" {
@@ -744,6 +753,7 @@ access :: proc(path: string, mask: int) -> (bool, Error) {
 	return true, nil
 }
 
+@(require_results)
 lookup_env :: proc(key: string, allocator := context.allocator) -> (value: string, found: bool) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == allocator)
 	path_str := strings.clone_to_cstring(key, context.temp_allocator)
@@ -754,11 +764,13 @@ lookup_env :: proc(key: string, allocator := context.allocator) -> (value: strin
 	return strings.clone(string(cstr), allocator), true
 }
 
+@(require_results)
 get_env :: proc(key: string, allocator := context.allocator) -> (value: string) {
 	value, _ = lookup_env(key, allocator)
 	return
 }
 
+@(require_results)
 get_current_directory :: proc() -> string {
 	buf := make([dynamic]u8, MAX_PATH)
 	for {
@@ -790,16 +802,19 @@ exit :: proc "contextless" (code: int) -> ! {
 	_unix_exit(c.int(code))
 }
 
+@(require_results)
 current_thread_id :: proc "contextless" () -> int {
 	return _unix_getthrid()
 }
 
+@(require_results)
 dlopen :: proc(filename: string, flags: int) -> rawptr {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
 	cstr := strings.clone_to_cstring(filename, context.temp_allocator)
 	handle := _unix_dlopen(cstr, c.int(flags))
 	return handle
 }
+@(require_results)
 dlsym :: proc(handle: rawptr, symbol: string) -> rawptr {
 	assert(handle != nil)
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
@@ -811,10 +826,12 @@ dlclose :: proc(handle: rawptr) -> bool {
 	assert(handle != nil)
 	return _unix_dlclose(handle) == 0
 }
+@(require_results)
 dlerror :: proc() -> string {
 	return string(_unix_dlerror())
 }
 
+@(require_results)
 get_page_size :: proc() -> int {
 	// NOTE(tetra): The page size never changes, so why do anything complicated
 	// if we don't have to.
@@ -829,11 +846,12 @@ get_page_size :: proc() -> int {
 
 _SC_NPROCESSORS_ONLN :: 503
 
-@(private)
+@(private, require_results)
 _processor_core_count :: proc() -> int {
 	return int(_sysconf(_SC_NPROCESSORS_ONLN))
 }
 
+@(require_results)
 _alloc_command_line_arguments :: proc() -> []string {
 	res := make([]string, len(runtime.args__))
 	for arg, i in runtime.args__ {

core/os/os_wasi.odin

@@ -27,6 +27,7 @@ stderr: Handle = 2
 
 args := _alloc_command_line_arguments()
 
+@(require_results)
 _alloc_command_line_arguments :: proc() -> (args: []string) {
 	args = make([]string, len(runtime.args__))
 	for &arg, i in args {
@@ -91,8 +92,9 @@ init_preopens :: proc() {
 	preopens = dyn_preopens[:]
 }
 
+@(require_results)
 wasi_match_preopen :: proc(path: string) -> (wasi.fd_t, string, bool) {
-
+	@(require_results)
 	prefix_matches :: proc(prefix, path: string) -> bool {
 		// Empty is valid for any relative path.
 		if len(prefix) == 0 && len(path) > 0 && path[0] != '/' {
@@ -163,6 +165,7 @@ read_at :: proc(fd: Handle, data: []byte, offset: i64) -> (int, Errno) {
 	n, err := wasi.fd_pread(wasi.fd_t(fd), {iovs}, wasi.filesize_t(offset))
 	return int(n), Platform_Error(err)
 }
+@(require_results)
 open :: proc(path: string, mode: int = O_RDONLY, perm: int = 0) -> (Handle, Errno) {
 	oflags: wasi.oflags_t
 	if mode & O_CREATE == O_CREATE {
@@ -215,14 +218,16 @@ seek :: proc(fd: Handle, offset: i64, whence: int) -> (i64, Errno) {
 	n, err := wasi.fd_seek(wasi.fd_t(fd), wasi.filedelta_t(offset), wasi.whence_t(whence))
 	return i64(n), Platform_Error(err)
 }
+@(require_results)
 current_thread_id :: proc "contextless" () -> int {
 	return 0
 }
-@(private)
+@(private, require_results)
 _processor_core_count :: proc() -> int {
 	return 1
 }
 
+@(require_results)
 file_size :: proc(fd: Handle) -> (size: i64, err: Errno) {
 	stat := wasi.fd_filestat_get(wasi.fd_t(fd)) or_return
 	size = i64(stat.size)

core/os/os_windows.odin

@@ -153,7 +153,7 @@ get_page_size :: proc() -> int {
 	return page_size
 }
 
-@(private)
+@(private, require_results)
 _processor_core_count :: proc() -> int {
 	length : win32.DWORD = 0
 	result := win32.GetLogicalProcessorInformation(nil, &length)
@@ -184,12 +184,14 @@ exit :: proc "contextless" (code: int) -> ! {
 
 
 
+@(require_results)
 current_thread_id :: proc "contextless" () -> int {
 	return int(win32.GetCurrentThreadId())
 }
 
 
 
+@(require_results)
 _alloc_command_line_arguments :: proc() -> []string {
 	arg_count: i32
 	arg_list_ptr := win32.CommandLineToArgvW(win32.GetCommandLineW(), &arg_count)
@@ -223,44 +225,52 @@ _alloc_command_line_arguments :: proc() -> []string {
 */
 WINDOWS_11_BUILD_CUTOFF :: 22_000
 
-get_windows_version_w :: proc() -> win32.OSVERSIONINFOEXW {
+@(require_results)
+get_windows_version_w :: proc "contextless" () -> win32.OSVERSIONINFOEXW {
 	osvi : win32.OSVERSIONINFOEXW
 	osvi.dwOSVersionInfoSize = size_of(win32.OSVERSIONINFOEXW)
 	win32.RtlGetVersion(&osvi)
 	return osvi
 }
 
-is_windows_xp :: proc() -> bool {
+@(require_results)
+is_windows_xp :: proc "contextless" () -> bool {
 	osvi := get_windows_version_w()
 	return (osvi.dwMajorVersion == 5 && osvi.dwMinorVersion == 1)
 }
 
-is_windows_vista :: proc() -> bool {
+@(require_results)
+is_windows_vista :: proc "contextless" () -> bool {
 	osvi := get_windows_version_w()
 	return (osvi.dwMajorVersion == 6 && osvi.dwMinorVersion == 0)
 }
 
-is_windows_7 :: proc() -> bool {
+@(require_results)
+is_windows_7 :: proc "contextless" () -> bool {
 	osvi := get_windows_version_w()
 	return (osvi.dwMajorVersion == 6 && osvi.dwMinorVersion == 1)
 }
 
-is_windows_8 :: proc() -> bool {
+@(require_results)
+is_windows_8 :: proc "contextless" () -> bool {
 	osvi := get_windows_version_w()
 	return (osvi.dwMajorVersion == 6 && osvi.dwMinorVersion == 2)
 }
 
-is_windows_8_1 :: proc() -> bool {
+@(require_results)
+is_windows_8_1 :: proc "contextless" () -> bool {
 	osvi := get_windows_version_w()
 	return (osvi.dwMajorVersion == 6 && osvi.dwMinorVersion == 3)
 }
 
-is_windows_10 :: proc() -> bool {
+@(require_results)
+is_windows_10 :: proc "contextless" () -> bool {
 	osvi := get_windows_version_w()
 	return (osvi.dwMajorVersion == 10 && osvi.dwMinorVersion == 0 && osvi.dwBuildNumber <  WINDOWS_11_BUILD_CUTOFF)
 }
 
-is_windows_11 :: proc() -> bool {
+@(require_results)
+is_windows_11 :: proc "contextless" () -> bool {
 	osvi := get_windows_version_w()
 	return (osvi.dwMajorVersion == 10 && osvi.dwMinorVersion == 0 && osvi.dwBuildNumber >= WINDOWS_11_BUILD_CUTOFF)
 }

core/os/stat_unix.odin

@@ -50,14 +50,14 @@ File_Info :: struct {
 }
 */
 
-@private
+@(private, require_results)
 _make_time_from_unix_file_time :: proc(uft: Unix_File_Time) -> time.Time {
 	return time.Time{
 		_nsec = uft.nanoseconds + uft.seconds * 1_000_000_000,
 	}
 }
 
-@private
+@(private)
 _fill_file_info_from_stat :: proc(fi: ^File_Info, s: OS_Stat) {
 	fi.size = s.size
 	fi.mode = cast(File_Mode)s.mode
@@ -71,7 +71,7 @@ _fill_file_info_from_stat :: proc(fi: ^File_Info, s: OS_Stat) {
 }
 
 
-@private
+@(private, require_results)
 path_base :: proc(path: string) -> string {
 	is_separator :: proc(c: byte) -> bool {
 		return c == '/'
@@ -100,6 +100,7 @@ path_base :: proc(path: string) -> string {
 }
 
 
+@(require_results)
 lstat :: proc(name: string, allocator := context.allocator) -> (fi: File_Info, err: Error) {
 	context.allocator = allocator
 
@@ -110,6 +111,7 @@ lstat :: proc(name: string, allocator := context.allocator) -> (fi: File_Info, e
 	return
 }
 
+@(require_results)
 stat :: proc(name: string, allocator := context.allocator) -> (fi: File_Info, err: Error) {
 	context.allocator = allocator
 
@@ -120,6 +122,7 @@ stat :: proc(name: string, allocator := context.allocator) -> (fi: File_Info, er
 	return
 }
 
+@(require_results)
 fstat :: proc(fd: Handle, allocator := context.allocator) -> (fi: File_Info, err: Error) {
 	context.allocator = allocator
 

core/os/stat_windows.odin

@@ -4,7 +4,7 @@ import "core:time"
 import "base:runtime"
 import win32 "core:sys/windows"
 
-@(private)
+@(private, require_results)
 full_path_from_name :: proc(name: string, allocator := context.allocator) -> (path: string, err: Errno) {
 	context.allocator = allocator
 	
@@ -30,7 +30,7 @@ full_path_from_name :: proc(name: string, allocator := context.allocator) -> (pa
 	return
 }
 
-@(private)
+@(private, require_results)
 _stat :: proc(name: string, create_file_attributes: u32, allocator := context.allocator) -> (fi: File_Info, e: Errno) {
 	if len(name) == 0 {
 		return {}, ERROR_PATH_NOT_FOUND
@@ -72,17 +72,20 @@ _stat :: proc(name: string, create_file_attributes: u32, allocator := context.al
 }
 
 
+@(require_results)
 lstat :: proc(name: string, allocator := context.allocator) -> (File_Info, Errno) {
 	attrs := win32.FILE_FLAG_BACKUP_SEMANTICS
 	attrs |= win32.FILE_FLAG_OPEN_REPARSE_POINT
 	return _stat(name, attrs, allocator)
 }
 
+@(require_results)
 stat :: proc(name: string, allocator := context.allocator) -> (File_Info, Errno) {
 	attrs := win32.FILE_FLAG_BACKUP_SEMANTICS
 	return _stat(name, attrs, allocator)
 }
 
+@(require_results)
 fstat :: proc(fd: Handle, allocator := context.allocator) -> (fi: File_Info, err: Errno) {
 	if fd == 0 {
 		err = ERROR_INVALID_HANDLE
@@ -108,7 +111,7 @@ fstat :: proc(fd: Handle, allocator := context.allocator) -> (fi: File_Info, err
 }
 
 
-@(private)
+@(private, require_results)
 cleanpath_strip_prefix :: proc(buf: []u16) -> []u16 {
 	buf := buf
 	N := 0
@@ -133,13 +136,13 @@ cleanpath_strip_prefix :: proc(buf: []u16) -> []u16 {
 	return buf
 }
 
-@(private)
+@(private, require_results)
 cleanpath_from_handle :: proc(fd: Handle) -> (s: string, err: Errno) {
 	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == context.allocator)
 	buf := cleanpath_from_handle_u16(fd, context.temp_allocator) or_return
 	return win32.utf16_to_utf8(buf, context.allocator)
 }
-@(private)
+@(private, require_results)
 cleanpath_from_handle_u16 :: proc(fd: Handle, allocator: runtime.Allocator) -> ([]u16, Errno) {
 	if fd == 0 {
 		return nil, ERROR_INVALID_HANDLE
@@ -154,14 +157,14 @@ cleanpath_from_handle_u16 :: proc(fd: Handle, allocator: runtime.Allocator) -> (
 	buf_len := win32.GetFinalPathNameByHandleW(h, raw_data(buf), n, 0)
 	return buf[:buf_len], nil
 }
-@(private)
+@(private, require_results)
 cleanpath_from_buf :: proc(buf: []u16) -> string {
 	buf := buf
 	buf = cleanpath_strip_prefix(buf)
 	return win32.utf16_to_utf8(buf, context.allocator) or_else ""
 }
 
-@(private)
+@(private, require_results)
 basename :: proc(name: string) -> (base: string) {
 	name := name
 	if len(name) > 3 && name[:3] == `\\?` {
@@ -187,7 +190,7 @@ basename :: proc(name: string) -> (base: string) {
 	return name
 }
 
-@(private)
+@(private, require_results)
 file_type_mode :: proc(h: win32.HANDLE) -> File_Mode {
 	switch win32.GetFileType(h) {
 	case win32.FILE_TYPE_PIPE:
@@ -199,7 +202,7 @@ file_type_mode :: proc(h: win32.HANDLE) -> File_Mode {
 }
 
 
-@(private)
+@(private, require_results)
 file_mode_from_file_attributes :: proc(FileAttributes: win32.DWORD, h: win32.HANDLE, ReparseTag: win32.DWORD) -> (mode: File_Mode) {
 	if FileAttributes & win32.FILE_ATTRIBUTE_READONLY != 0 {
 		mode |= 0o444
@@ -236,7 +239,7 @@ windows_set_file_info_times :: proc(fi: ^File_Info, d: ^$T) {
 	fi.access_time       = time.unix(0, win32.FILETIME_as_unix_nanoseconds(d.ftLastAccessTime))
 }
 
-@(private)
+@(private, require_results)
 file_info_from_win32_file_attribute_data :: proc(d: ^win32.WIN32_FILE_ATTRIBUTE_DATA, name: string) -> (fi: File_Info, e: Errno) {
 	fi.size = i64(d.nFileSizeHigh)<<32 + i64(d.nFileSizeLow)
 
@@ -251,7 +254,7 @@ file_info_from_win32_file_attribute_data :: proc(d: ^win32.WIN32_FILE_ATTRIBUTE_
 	return
 }
 
-@(private)
+@(private, require_results)
 file_info_from_win32_find_data :: proc(d: ^win32.WIN32_FIND_DATAW, name: string) -> (fi: File_Info, e: Errno) {
 	fi.size = i64(d.nFileSizeHigh)<<32 + i64(d.nFileSizeLow)
 
@@ -266,7 +269,7 @@ file_info_from_win32_find_data :: proc(d: ^win32.WIN32_FIND_DATAW, name: string)
 	return
 }
 
-@(private)
+@(private, require_results)
 file_info_from_get_file_information_by_handle :: proc(path: string, h: win32.HANDLE) -> (File_Info, Errno) {
 	d: win32.BY_HANDLE_FILE_INFORMATION
 	if !win32.GetFileInformationByHandle(h, &d) {