Remove #[fixed_stack_segment] and #[rust_stack]

These two attributes are no longer useful now that Rust has decided to leave
segmented stacks behind. It is assumed that the rust task's stack is always
large enough to make an FFI call (due to the stack being very large).

There's always the case of stack overflow, however, to consider. This does not
change the behavior of stack overflow in Rust. This is still normally triggered
by the __morestack function and aborts the whole process.

C stack overflow will continue to corrupt the stack, however (as it did before
this commit as well). The future improvement of a guard page at the end of every
rust stack is still unimplemented and is intended to be the mechanism through
which we attempt to detect C stack overflow.

Closes #8822
Closes #10155

1 files changed, 4 insertions, 56 deletions

diff --git a/src/libstd/os.rs b/src/libstd/os.rs
index de4fb54be95..ff24c35d4e6 100644
--- a/src/libstd/os.rs
+++ b/src/libstd/os.rs
@@ -47,7 +47,6 @@ pub use os::consts::*;
 
 /// Delegates to the libc close() function, returning the same return value.
 pub fn close(fd: c_int) -> c_int {
-    #[fixed_stack_segment]; #[inline(never)];
     unsafe {
         libc::close(fd)
     }
@@ -58,7 +57,6 @@ static BUF_BYTES : uint = 2048u;
 
 #[cfg(unix)]
 pub fn getcwd() -> Path {
-    #[fixed_stack_segment]; #[inline(never)];
     let mut buf = [0 as libc::c_char, ..BUF_BYTES];
     do buf.as_mut_buf |buf, len| {
         unsafe {
@@ -73,7 +71,6 @@ pub fn getcwd() -> Path {
 
 #[cfg(windows)]
 pub fn getcwd() -> Path {
-    #[fixed_stack_segment]; #[inline(never)];
     use libc::DWORD;
     use libc::GetCurrentDirectoryW;
     let mut buf = [0 as u16, ..BUF_BYTES];
@@ -99,7 +96,6 @@ pub mod win32 {
 
     pub fn fill_utf16_buf_and_decode(f: &fn(*mut u16, DWORD) -> DWORD)
         -> Option<~str> {
-        #[fixed_stack_segment]; #[inline(never)];
 
         unsafe {
             let mut n = TMPBUF_SZ as DWORD;
@@ -153,8 +149,10 @@ fn with_env_lock<T>(f: &fn() -> T) -> T {
         };
     }
 
-    externfn!(fn rust_take_env_lock());
-    externfn!(fn rust_drop_env_lock());
+    extern {
+        fn rust_take_env_lock();
+        fn rust_drop_env_lock();
+    }
 }
 
 /// Returns a vector of (variable, value) pairs for all the environment
@@ -163,7 +161,6 @@ pub fn env() -> ~[(~str,~str)] {
     unsafe {
         #[cfg(windows)]
         unsafe fn get_env_pairs() -> ~[~str] {
-            #[fixed_stack_segment]; #[inline(never)];
             use c_str;
             use str::StrSlice;
 
@@ -185,8 +182,6 @@ pub fn env() -> ~[(~str,~str)] {
         }
         #[cfg(unix)]
         unsafe fn get_env_pairs() -> ~[~str] {
-            #[fixed_stack_segment]; #[inline(never)];
-
             extern {
                 fn rust_env_pairs() -> **libc::c_char;
             }
@@ -225,7 +220,6 @@ pub fn env() -> ~[(~str,~str)] {
 /// Fetches the environment variable `n` from the current process, returning
 /// None if the variable isn't set.
 pub fn getenv(n: &str) -> Option<~str> {
-    #[fixed_stack_segment]; #[inline(never)];
     unsafe {
         do with_env_lock {
             let s = do n.with_c_str |buf| {
@@ -244,8 +238,6 @@ pub fn getenv(n: &str) -> Option<~str> {
 /// Fetches the environment variable `n` from the current process, returning
 /// None if the variable isn't set.
 pub fn getenv(n: &str) -> Option<~str> {
-    #[fixed_stack_segment]; #[inline(never)];
-
     unsafe {
         do with_env_lock {
             use os::win32::{as_utf16_p, fill_utf16_buf_and_decode};
@@ -263,7 +255,6 @@ pub fn getenv(n: &str) -> Option<~str> {
 /// Sets the environment variable `n` to the value `v` for the currently running
 /// process
 pub fn setenv(n: &str, v: &str) {
-    #[fixed_stack_segment]; #[inline(never)];
     unsafe {
         do with_env_lock {
             do n.with_c_str |nbuf| {
@@ -280,8 +271,6 @@ pub fn setenv(n: &str, v: &str) {
 /// Sets the environment variable `n` to the value `v` for the currently running
 /// process
 pub fn setenv(n: &str, v: &str) {
-    #[fixed_stack_segment]; #[inline(never)];
-
     unsafe {
         do with_env_lock {
             use os::win32::as_utf16_p;
@@ -298,7 +287,6 @@ pub fn setenv(n: &str, v: &str) {
 pub fn unsetenv(n: &str) {
     #[cfg(unix)]
     fn _unsetenv(n: &str) {
-        #[fixed_stack_segment]; #[inline(never)];
         unsafe {
             do with_env_lock {
                 do n.with_c_str |nbuf| {
@@ -309,7 +297,6 @@ pub fn unsetenv(n: &str) {
     }
     #[cfg(windows)]
     fn _unsetenv(n: &str) {
-        #[fixed_stack_segment]; #[inline(never)];
         unsafe {
             do with_env_lock {
                 use os::win32::as_utf16_p;
@@ -330,7 +317,6 @@ pub struct Pipe {
 
 #[cfg(unix)]
 pub fn pipe() -> Pipe {
-    #[fixed_stack_segment]; #[inline(never)];
     unsafe {
         let mut fds = Pipe {input: 0 as c_int,
                             out: 0 as c_int };
@@ -341,7 +327,6 @@ pub fn pipe() -> Pipe {
 
 #[cfg(windows)]
 pub fn pipe() -> Pipe {
-    #[fixed_stack_segment]; #[inline(never)];
     unsafe {
         // Windows pipes work subtly differently than unix pipes, and their
         // inheritance has to be handled in a different way that I do not
@@ -360,7 +345,6 @@ pub fn pipe() -> Pipe {
 }
 
 fn dup2(src: c_int, dst: c_int) -> c_int {
-    #[fixed_stack_segment]; #[inline(never)];
     unsafe {
         libc::dup2(src, dst)
     }
@@ -377,7 +361,6 @@ pub fn self_exe_path() -> Option<Path> {
 
     #[cfg(target_os = "freebsd")]
     fn load_self() -> Option<~[u8]> {
-        #[fixed_stack_segment]; #[inline(never)];
         unsafe {
             use libc::funcs::bsd44::*;
             use libc::consts::os::extra::*;
@@ -415,7 +398,6 @@ pub fn self_exe_path() -> Option<Path> {
 
     #[cfg(target_os = "macos")]
     fn load_self() -> Option<~[u8]> {
-        #[fixed_stack_segment]; #[inline(never)];
         unsafe {
             use libc::funcs::extra::_NSGetExecutablePath;
             use vec;
@@ -434,7 +416,6 @@ pub fn self_exe_path() -> Option<Path> {
 
     #[cfg(windows)]
     fn load_self() -> Option<~[u8]> {
-        #[fixed_stack_segment]; #[inline(never)];
         unsafe {
             use os::win32::fill_utf16_buf_and_decode;
             do fill_utf16_buf_and_decode() |buf, sz| {
@@ -555,7 +536,6 @@ pub fn change_dir(p: &Path) -> bool {
 
     #[cfg(windows)]
     fn chdir(p: &Path) -> bool {
-        #[fixed_stack_segment]; #[inline(never)];
         unsafe {
             use os::win32::as_utf16_p;
             return do as_utf16_p(p.as_str().unwrap()) |buf| {
@@ -566,7 +546,6 @@ pub fn change_dir(p: &Path) -> bool {
 
     #[cfg(unix)]
     fn chdir(p: &Path) -> bool {
-        #[fixed_stack_segment]; #[inline(never)];
         do p.with_c_str |buf| {
             unsafe {
                 libc::chdir(buf) == (0 as c_int)
@@ -581,7 +560,6 @@ pub fn errno() -> int {
     #[cfg(target_os = "macos")]
     #[cfg(target_os = "freebsd")]
     fn errno_location() -> *c_int {
-        #[fixed_stack_segment]; #[inline(never)];
         #[nolink]
         extern {
             fn __error() -> *c_int;
@@ -594,7 +572,6 @@ pub fn errno() -> int {
     #[cfg(target_os = "linux")]
     #[cfg(target_os = "android")]
     fn errno_location() -> *c_int {
-        #[fixed_stack_segment]; #[inline(never)];
         #[nolink]
         extern {
             fn __errno_location() -> *c_int;
@@ -612,7 +589,6 @@ pub fn errno() -> int {
 #[cfg(windows)]
 /// Returns the platform-specific value of errno
 pub fn errno() -> uint {
-    #[fixed_stack_segment]; #[inline(never)];
     use libc::types::os::arch::extra::DWORD;
 
     #[link_name = "kernel32"]
@@ -634,8 +610,6 @@ pub fn last_os_error() -> ~str {
         #[cfg(target_os = "freebsd")]
         fn strerror_r(errnum: c_int, buf: *mut c_char, buflen: size_t)
                       -> c_int {
-            #[fixed_stack_segment]; #[inline(never)];
-
             #[nolink]
             extern {
                 fn strerror_r(errnum: c_int, buf: *mut c_char, buflen: size_t)
@@ -651,7 +625,6 @@ pub fn last_os_error() -> ~str {
         // So we just use __xpg_strerror_r which is always POSIX compliant
         #[cfg(target_os = "linux")]
         fn strerror_r(errnum: c_int, buf: *mut c_char, buflen: size_t) -> c_int {
-            #[fixed_stack_segment]; #[inline(never)];
             #[nolink]
             extern {
                 fn __xpg_strerror_r(errnum: c_int,
@@ -679,8 +652,6 @@ pub fn last_os_error() -> ~str {
 
     #[cfg(windows)]
     fn strerror() -> ~str {
-        #[fixed_stack_segment]; #[inline(never)];
-
         use libc::types::os::arch::extra::DWORD;
         use libc::types::os::arch::extra::LPWSTR;
         use libc::types::os::arch::extra::LPVOID;
@@ -758,8 +729,6 @@ unsafe fn load_argc_and_argv(argc: c_int, argv: **c_char) -> ~[~str] {
  */
 #[cfg(target_os = "macos")]
 fn real_args() -> ~[~str] {
-    #[fixed_stack_segment]; #[inline(never)];
-
     unsafe {
         let (argc, argv) = (*_NSGetArgc() as c_int,
                             *_NSGetArgv() as **c_char);
@@ -781,7 +750,6 @@ fn real_args() -> ~[~str] {
 
 #[cfg(windows)]
 fn real_args() -> ~[~str] {
-    #[fixed_stack_segment]; #[inline(never)];
     use vec;
 
     let mut nArgs: c_int = 0;
@@ -858,8 +826,6 @@ fn round_up(from: uint, to: uint) -> uint {
 
 #[cfg(unix)]
 pub fn page_size() -> uint {
-    #[fixed_stack_segment]; #[inline(never)];
-
     unsafe {
         libc::sysconf(libc::_SC_PAGESIZE) as uint
     }
@@ -867,8 +833,6 @@ pub fn page_size() -> uint {
 
 #[cfg(windows)]
 pub fn page_size() -> uint {
-    #[fixed_stack_segment]; #[inline(never)];
-
     unsafe {
         let mut info = libc::SYSTEM_INFO::new();
         libc::GetSystemInfo(&mut info);
@@ -979,8 +943,6 @@ impl to_str::ToStr for MapError {
 impl MemoryMap {
     /// Create a new mapping with the given `options`, at least `min_len` bytes long.
     pub fn new(min_len: uint, options: &[MapOption]) -> Result<MemoryMap, MapError> {
-        #[fixed_stack_segment]; #[inline(never)];
-
         use libc::off_t;
 
         let mut addr: *c_void = ptr::null();
@@ -1043,8 +1005,6 @@ impl MemoryMap {
 impl Drop for MemoryMap {
     /// Unmap the mapping. Fails the task if `munmap` fails.
     fn drop(&mut self) {
-        #[fixed_stack_segment]; #[inline(never)];
-
         unsafe {
             match libc::munmap(self.data as *c_void, self.len) {
                 0 => (),
@@ -1062,8 +1022,6 @@ impl Drop for MemoryMap {
 impl MemoryMap {
     /// Create a new mapping with the given `options`, at least `min_len` bytes long.
     pub fn new(min_len: uint, options: &[MapOption]) -> Result<MemoryMap, MapError> {
-        #[fixed_stack_segment]; #[inline(never)];
-
         use libc::types::os::arch::extra::{LPVOID, DWORD, SIZE_T, HANDLE};
 
         let mut lpAddress: LPVOID = ptr::mut_null();
@@ -1156,8 +1114,6 @@ impl MemoryMap {
     /// Granularity of MapAddr() and MapOffset() parameter values.
     /// This may be greater than the value returned by page_size().
     pub fn granularity() -> uint {
-        #[fixed_stack_segment]; #[inline(never)];
-
         unsafe {
             let mut info = libc::SYSTEM_INFO::new();
             libc::GetSystemInfo(&mut info);
@@ -1172,8 +1128,6 @@ impl Drop for MemoryMap {
     /// Unmap the mapping. Fails the task if any of `VirtualFree`, `UnmapViewOfFile`, or
     /// `CloseHandle` fail.
     fn drop(&mut self) {
-        #[fixed_stack_segment]; #[inline(never)];
-
         use libc::types::os::arch::extra::{LPCVOID, HANDLE};
         use libc::consts::os::extra::FALSE;
 
@@ -1490,8 +1444,6 @@ mod tests {
 
     #[test]
     fn memory_map_file() {
-        #[fixed_stack_segment]; #[inline(never)];
-
         use result::{Ok, Err};
         use os::*;
         use libc::*;
@@ -1499,16 +1451,12 @@ mod tests {
         use rt::io::fs;
 
         #[cfg(unix)]
-        #[fixed_stack_segment]
-        #[inline(never)]
         fn lseek_(fd: c_int, size: uint) {
             unsafe {
                 assert!(lseek(fd, size as off_t, SEEK_SET) == size as off_t);
             }
         }
         #[cfg(windows)]
-        #[fixed_stack_segment]
-        #[inline(never)]
         fn lseek_(fd: c_int, size: uint) {
            unsafe {
                assert!(lseek(fd, size as c_long, SEEK_SET) == size as c_long);