Rollup merge of #136844 - thaliaarchi:const-io-error, r=ChrisDenton

Use `const_error!` when possible

Replace usages of `io::Error::new(io::ErrorKind::Variant, "constant string")` with `io::const_error!(io::ErrorKind::Variant, "constant string")` to avoid allocations when possible. Additionally, fix `&&str` error messages in SGX and missing/misplaced trailing commas in `const_error!`.

library/std/src/io/error.rs

@@ -83,7 +83,7 @@ impl Error {
 
     pub(crate) const UNKNOWN_THREAD_COUNT: Self = const_error!(
         ErrorKind::NotFound,
-        "The number of hardware threads is not known for the target platform"
+        "The number of hardware threads is not known for the target platform",
     );
 
     pub(crate) const UNSUPPORTED_PLATFORM: Self =

library/std/src/path.rs

@@ -3575,7 +3575,7 @@ impl Error for StripPrefixError {
 pub fn absolute<P: AsRef<Path>>(path: P) -> io::Result<PathBuf> {
     let path = path.as_ref();
     if path.as_os_str().is_empty() {
-        Err(io::const_error!(io::ErrorKind::InvalidInput, "cannot make an empty path absolute",))
+        Err(io::const_error!(io::ErrorKind::InvalidInput, "cannot make an empty path absolute"))
     } else {
         sys::path::absolute(path)
     }

library/std/src/sys/net/connection/xous/dns.rs

@@ -123,6 +123,6 @@ impl TryFrom<(&str, u16)> for LookupHost {
     type Error = io::Error;
 
     fn try_from(v: (&str, u16)) -> io::Result<LookupHost> {
-        lookup(v.0, v.1).map_err(|_e| io::const_error!(io::ErrorKind::InvalidInput, &"DNS failure"))
+        lookup(v.0, v.1).map_err(|_e| io::const_error!(io::ErrorKind::InvalidInput, "DNS failure"))
     }
 }

library/std/src/sys/net/connection/xous/tcplistener.rs

@@ -11,7 +11,7 @@ macro_rules! unimpl {
     () => {
         return Err(io::const_error!(
             io::ErrorKind::Unsupported,
-            &"This function is not yet implemented",
+            "This function is not yet implemented",
         ));
     };
 }
@@ -71,7 +71,7 @@ impl TcpListener {
             0,
             4096,
         ) else {
-            return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Invalid response"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "Invalid response"));
         };
 
         // The first four bytes should be zero upon success, and will be nonzero
@@ -80,15 +80,15 @@ impl TcpListener {
         if response[0] != 0 || valid == 0 {
             let errcode = response[1];
             if errcode == NetError::SocketInUse as u8 {
-                return Err(io::const_error!(io::ErrorKind::ResourceBusy, &"Socket in use"));
+                return Err(io::const_error!(io::ErrorKind::ResourceBusy, "Socket in use"));
             } else if errcode == NetError::Invalid as u8 {
-                return Err(io::const_error!(io::ErrorKind::AddrNotAvailable, &"Invalid address"));
+                return Err(io::const_error!(io::ErrorKind::AddrNotAvailable, "Invalid address"));
             } else if errcode == NetError::LibraryError as u8 {
-                return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
+                return Err(io::const_error!(io::ErrorKind::Other, "Library error"));
             } else {
                 return Err(io::const_error!(
                     io::ErrorKind::Other,
-                    &"Unable to connect or internal error"
+                    "Unable to connect or internal error",
                 ));
             }
         }
@@ -127,15 +127,13 @@ impl TcpListener {
             if receive_request.raw[0] != 0 {
                 // error case
                 if receive_request.raw[1] == NetError::TimedOut as u8 {
-                    return Err(io::const_error!(io::ErrorKind::TimedOut, &"accept timed out",));
+                    return Err(io::const_error!(io::ErrorKind::TimedOut, "accept timed out"));
                 } else if receive_request.raw[1] == NetError::WouldBlock as u8 {
-                    return Err(
+                    return Err(io::const_error!(io::ErrorKind::WouldBlock, "accept would block"));
-                        io::const_error!(io::ErrorKind::WouldBlock, &"accept would block",),
-                    );
                 } else if receive_request.raw[1] == NetError::LibraryError as u8 {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
+                    return Err(io::const_error!(io::ErrorKind::Other, "Library error"));
                 } else {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, "library error"));
                 }
             } else {
                 // accept successful
@@ -159,7 +157,7 @@ impl TcpListener {
                         port,
                     )
                 } else {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, "library error"));
                 };
 
                 // replenish the listener
@@ -171,7 +169,7 @@ impl TcpListener {
                 Ok((TcpStream::from_listener(stream_fd, self.local.port(), port, addr), addr))
             }
         } else {
-            Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unable to accept"))
+            Err(io::const_error!(io::ErrorKind::InvalidInput, "Unable to accept"))
         }
     }
 
@@ -182,13 +180,13 @@ impl TcpListener {
 
     pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
         if ttl > 255 {
-            return Err(io::Error::new(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
         }
         crate::os::xous::ffi::blocking_scalar(
             services::net_server(),
             services::NetBlockingScalar::StdSetTtlTcp(self.fd.load(Ordering::Relaxed), ttl).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|_| ())
     }
 
@@ -197,7 +195,7 @@ impl TcpListener {
             services::net_server(),
             services::NetBlockingScalar::StdGetTtlTcp(self.fd.load(Ordering::Relaxed)).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|res| res[0] as _)?)
     }
 

library/std/src/sys/net/connection/xous/tcpstream.rs

@@ -12,7 +12,7 @@ macro_rules! unimpl {
     () => {
         return Err(io::const_error!(
             io::ErrorKind::Unsupported,
-            &"This function is not yet implemented",
+            "This function is not yet implemented",
         ));
     };
 }
@@ -96,7 +96,7 @@ impl TcpStream {
             0,
             4096,
         ) else {
-            return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Invalid response"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "Invalid response"));
         };
 
         // The first four bytes should be zero upon success, and will be nonzero
@@ -106,13 +106,13 @@ impl TcpStream {
             // errcode is a u8 but stuck in a u16 where the upper byte is invalid. Mask & decode accordingly.
             let errcode = response[0];
             if errcode == NetError::SocketInUse as u8 {
-                return Err(io::const_error!(io::ErrorKind::ResourceBusy, &"Socket in use",));
+                return Err(io::const_error!(io::ErrorKind::ResourceBusy, "Socket in use"));
             } else if errcode == NetError::Unaddressable as u8 {
-                return Err(io::const_error!(io::ErrorKind::AddrNotAvailable, &"Invalid address",));
+                return Err(io::const_error!(io::ErrorKind::AddrNotAvailable, "Invalid address"));
             } else {
                 return Err(io::const_error!(
                     io::ErrorKind::InvalidInput,
-                    &"Unable to connect or internal error",
+                    "Unable to connect or internal error",
                 ));
             }
         }
@@ -198,7 +198,7 @@ impl TcpStream {
         ) else {
             return Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
-                &"Library failure: wrong message type or messaging error"
+                "Library failure: wrong message type or messaging error",
             ));
         };
 
@@ -212,14 +212,14 @@ impl TcpStream {
             if result[0] != 0 {
                 if result[1] == 8 {
                     // timed out
-                    return Err(io::const_error!(io::ErrorKind::TimedOut, &"Timeout",));
+                    return Err(io::const_error!(io::ErrorKind::TimedOut, "Timeout"));
                 }
                 if result[1] == 9 {
                     // would block
-                    return Err(io::const_error!(io::ErrorKind::WouldBlock, &"Would block",));
+                    return Err(io::const_error!(io::ErrorKind::WouldBlock, "Would block"));
                 }
             }
-            Err(io::const_error!(io::ErrorKind::Other, &"recv_slice failure"))
+            Err(io::const_error!(io::ErrorKind::Other, "recv_slice failure"))
         }
     }
 
@@ -258,20 +258,20 @@ impl TcpStream {
             self.write_timeout.load(Ordering::Relaxed) as usize,
             buf_len,
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Internal error")))?;
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Internal error")))?;
 
         if send_request.raw[0] != 0 {
             if send_request.raw[4] == 8 {
                 // timed out
                 return Err(io::const_error!(
                     io::ErrorKind::BrokenPipe,
-                    &"Timeout or connection closed",
+                    "Timeout or connection closed",
                 ));
             } else if send_request.raw[4] == 9 {
                 // would block
-                return Err(io::const_error!(io::ErrorKind::WouldBlock, &"Would block",));
+                return Err(io::const_error!(io::ErrorKind::WouldBlock, "Would block"));
             } else {
-                return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Error when sending",));
+                return Err(io::const_error!(io::ErrorKind::InvalidInput, "Error when sending"));
             }
         }
         Ok(u32::from_le_bytes([
@@ -304,7 +304,7 @@ impl TcpStream {
             0,
             0,
         ) else {
-            return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Internal error"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "Internal error"));
         };
         let mut i = get_addr.raw.iter();
         match *i.next().unwrap() {
@@ -324,7 +324,7 @@ impl TcpStream {
                 }
                 Ok(SocketAddr::V6(SocketAddrV6::new(new_addr.into(), self.local_port, 0, 0)))
             }
-            _ => Err(io::const_error!(io::ErrorKind::InvalidInput, &"Internal error")),
+            _ => Err(io::const_error!(io::ErrorKind::InvalidInput, "Internal error")),
         }
     }
 
@@ -333,7 +333,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdTcpStreamShutdown(self.fd, how).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|_| ())
     }
 
@@ -355,7 +355,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdSetNodelay(self.fd, enabled).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|_| ())
     }
 
@@ -364,19 +364,19 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdGetNodelay(self.fd).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|res| res[0] != 0)?)
     }
 
     pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
         if ttl > 255 {
-            return Err(io::Error::new(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
         }
         crate::os::xous::ffi::blocking_scalar(
             services::net_server(),
             services::NetBlockingScalar::StdSetTtlTcp(self.fd, ttl).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|_| ())
     }
 
@@ -385,7 +385,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdGetTtlTcp(self.fd).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|res| res[0] as _)?)
     }
 

library/std/src/sys/net/connection/xous/udp.rs

@@ -13,7 +13,7 @@ macro_rules! unimpl {
     () => {
         return Err(io::const_error!(
             io::ErrorKind::Unsupported,
-            &"This function is not yet implemented",
+            "This function is not yet implemented",
         ));
     };
 }
@@ -72,18 +72,18 @@ impl UdpSocket {
             if response[0] != 0 || valid == 0 {
                 let errcode = response[1];
                 if errcode == NetError::SocketInUse as u8 {
-                    return Err(io::const_error!(io::ErrorKind::ResourceBusy, &"Socket in use"));
+                    return Err(io::const_error!(io::ErrorKind::ResourceBusy, "Socket in use"));
                 } else if errcode == NetError::Invalid as u8 {
                     return Err(io::const_error!(
                         io::ErrorKind::InvalidInput,
-                        &"Port can't be 0 or invalid address"
+                        "Port can't be 0 or invalid address",
                     ));
                 } else if errcode == NetError::LibraryError as u8 {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
+                    return Err(io::const_error!(io::ErrorKind::Other, "Library error"));
                 } else {
                     return Err(io::const_error!(
                         io::ErrorKind::Other,
-                        &"Unable to connect or internal error"
+                        "Unable to connect or internal error",
                     ));
                 }
             }
@@ -98,13 +98,13 @@ impl UdpSocket {
                 nonblocking: Cell::new(false),
             });
         }
-        Err(io::const_error!(io::ErrorKind::InvalidInput, &"Invalid response"))
+        Err(io::const_error!(io::ErrorKind::InvalidInput, "Invalid response"))
     }
 
     pub fn peer_addr(&self) -> io::Result<SocketAddr> {
         match self.remote.get() {
             Some(dest) => Ok(dest),
-            None => Err(io::const_error!(io::ErrorKind::NotConnected, &"No peer specified")),
+            None => Err(io::const_error!(io::ErrorKind::NotConnected, "No peer specified")),
         }
     }
 
@@ -141,13 +141,13 @@ impl UdpSocket {
             if receive_request.raw[0] != 0 {
                 // error case
                 if receive_request.raw[1] == NetError::TimedOut as u8 {
-                    return Err(io::const_error!(io::ErrorKind::TimedOut, &"recv timed out",));
+                    return Err(io::const_error!(io::ErrorKind::TimedOut, "recv timed out"));
                 } else if receive_request.raw[1] == NetError::WouldBlock as u8 {
-                    return Err(io::const_error!(io::ErrorKind::WouldBlock, &"recv would block",));
+                    return Err(io::const_error!(io::ErrorKind::WouldBlock, "recv would block"));
                 } else if receive_request.raw[1] == NetError::LibraryError as u8 {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
+                    return Err(io::const_error!(io::ErrorKind::Other, "Library error"));
                 } else {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, "library error"));
                 }
             } else {
                 let rr = &receive_request.raw;
@@ -170,7 +170,7 @@ impl UdpSocket {
                         port,
                     )
                 } else {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, "library error"));
                 };
                 for (&s, d) in rr[22..22 + rxlen as usize].iter().zip(buf.iter_mut()) {
                     *d = s;
@@ -178,7 +178,7 @@ impl UdpSocket {
                 Ok((rxlen as usize, addr))
             }
         } else {
-            Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unable to recv"))
+            Err(io::const_error!(io::ErrorKind::InvalidInput, "Unable to recv"))
         }
     }
 
@@ -208,7 +208,7 @@ impl UdpSocket {
         if let Some(addr) = self.remote.get() {
             self.send_to(buf, &addr)
         } else {
-            Err(io::const_error!(io::ErrorKind::NotConnected, &"No remote specified"))
+            Err(io::const_error!(io::ErrorKind::NotConnected, "No remote specified"))
         }
     }
 
@@ -281,19 +281,19 @@ impl UdpSocket {
                         if errcode == NetError::SocketInUse as u8 {
                             return Err(io::const_error!(
                                 io::ErrorKind::ResourceBusy,
-                                &"Socket in use"
+                                "Socket in use",
                             ));
                         } else if errcode == NetError::Invalid as u8 {
                             return Err(io::const_error!(
                                 io::ErrorKind::InvalidInput,
-                                &"Socket not valid"
+                                "Socket not valid",
                             ));
                         } else if errcode == NetError::LibraryError as u8 {
-                            return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
+                            return Err(io::const_error!(io::ErrorKind::Other, "Library error"));
                         } else {
                             return Err(io::const_error!(
                                 io::ErrorKind::Other,
-                                &"Unable to connect"
+                                "Unable to connect",
                             ));
                         }
                     } else {
@@ -303,16 +303,13 @@ impl UdpSocket {
                 }
                 Err(crate::os::xous::ffi::Error::ServerQueueFull) => {
                     if now.elapsed() >= write_timeout {
-                        return Err(io::const_error!(
+                        return Err(io::const_error!(io::ErrorKind::WouldBlock, "Write timed out"));
-                            io::ErrorKind::WouldBlock,
-                            &"Write timed out"
-                        ));
                     } else {
                         // question: do we want to do something a bit more gentle than immediately retrying?
                         crate::thread::yield_now();
                     }
                 }
-                _ => return Err(io::const_error!(io::ErrorKind::Other, &"Library error")),
+                _ => return Err(io::const_error!(io::ErrorKind::Other, "Library error")),
             }
         }
     }
@@ -360,13 +357,13 @@ impl UdpSocket {
 
     pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
         if ttl > 255 {
-            return Err(io::Error::new(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
         }
         crate::os::xous::ffi::blocking_scalar(
             services::net_server(),
             services::NetBlockingScalar::StdSetTtlUdp(self.fd, ttl).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|_| ())
     }
 
@@ -375,7 +372,7 @@ impl UdpSocket {
             services::net_server(),
             services::NetBlockingScalar::StdGetTtlUdp(self.fd).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|res| res[0] as _)?)
     }
 
@@ -441,7 +438,7 @@ impl UdpSocket {
 
 impl fmt::Debug for UdpSocket {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "UDP listening on {:?} to {:?}", self.local, self.remote.get(),)
+        write!(f, "UDP listening on {:?} to {:?}", self.local, self.remote.get())
     }
 }
 

library/std/src/sys/pal/hermit/fs.rs

@@ -304,16 +304,12 @@ impl OpenOptions {
             (true, false) => {}
             (false, false) => {
                 if self.truncate || self.create || self.create_new {
-                    return Err(
+                    return Err(io::const_error!(ErrorKind::InvalidInput, "invalid creation mode"));
-                        io::const_error!(ErrorKind::InvalidInput, "invalid creation mode",),
-                    );
                 }
             }
             (_, true) => {
                 if self.truncate && !self.create_new {
-                    return Err(
+                    return Err(io::const_error!(ErrorKind::InvalidInput, "invalid creation mode"));
-                        io::const_error!(ErrorKind::InvalidInput, "invalid creation mode",),
-                    );
                 }
             }
         }

library/std/src/sys/pal/solid/fs.rs

@@ -309,7 +309,7 @@ fn cstr(path: &Path) -> io::Result<CString> {
     let wrapped_path = [SAFE_PREFIX, &path, &[0]].concat();
 
     CString::from_vec_with_nul(wrapped_path).map_err(|_| {
-        crate::io::const_error!(io::ErrorKind::InvalidInput, "path provided contains a nul byte",)
+        crate::io::const_error!(io::ErrorKind::InvalidInput, "path provided contains a nul byte")
     })
 }
 

library/std/src/sys/pal/teeos/mod.rs

@@ -148,5 +148,5 @@ pub fn unsupported<T>() -> std_io::Result<T> {
 }
 
 pub fn unsupported_err() -> std_io::Error {
-    std_io::Error::new(std_io::ErrorKind::Unsupported, "operation not supported on this platform")
+    std_io::Error::UNSUPPORTED_PLATFORM
 }

library/std/src/sys/pal/teeos/os.rs

@@ -107,11 +107,11 @@ pub fn getenv(_: &OsStr) -> Option<OsString> {
 }
 
 pub unsafe fn setenv(_: &OsStr, _: &OsStr) -> io::Result<()> {
-    Err(io::Error::new(io::ErrorKind::Unsupported, "cannot set env vars on this platform"))
+    Err(io::const_error!(io::ErrorKind::Unsupported, "cannot set env vars on this platform"))
 }
 
 pub unsafe fn unsetenv(_: &OsStr) -> io::Result<()> {
-    Err(io::Error::new(io::ErrorKind::Unsupported, "cannot unset env vars on this platform"))
+    Err(io::const_error!(io::ErrorKind::Unsupported, "cannot unset env vars on this platform"))
 }
 
 pub fn temp_dir() -> PathBuf {

library/std/src/sys/pal/uefi/helpers.rs

@@ -273,7 +273,7 @@ impl OwnedDevicePath {
 
         io::Result::Err(const_error!(
             io::ErrorKind::NotFound,
-            "DevicePathFromText Protocol not found"
+            "DevicePathFromText Protocol not found",
         ))
     }
 

library/std/src/sys/pal/uefi/mod.rs

@@ -90,7 +90,7 @@ pub const fn unsupported<T>() -> std_io::Result<T> {
 
 #[inline]
 pub const fn unsupported_err() -> std_io::Error {
-    std_io::const_error!(std_io::ErrorKind::Unsupported, "operation not supported on UEFI",)
+    std_io::const_error!(std_io::ErrorKind::Unsupported, "operation not supported on UEFI")
 }
 
 pub fn decode_error_kind(code: RawOsError) -> crate::io::ErrorKind {

library/std/src/sys/pal/uefi/stdio.rs

@@ -71,7 +71,7 @@ impl io::Read for Stdin {
             };
 
         if ch.len() > 1 {
-            return Err(io::Error::new(io::ErrorKind::InvalidData, "invalid utf-16 sequence"));
+            return Err(io::const_error!(io::ErrorKind::InvalidData, "invalid utf-16 sequence"));
         }
 
         match ch.pop().unwrap() {

library/std/src/sys/pal/unix/fs.rs

@@ -568,8 +568,7 @@ impl FileAttr {
 
         Err(io::const_error!(
             io::ErrorKind::Unsupported,
-            "creation time is not available on this platform \
+            "creation time is not available on this platform currently",
-                            currently",
         ))
     }
 
@@ -1459,11 +1458,11 @@ impl File {
             Some(time) if let Some(ts) = time.t.to_timespec() => Ok(ts),
             Some(time) if time > crate::sys::time::UNIX_EPOCH => Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
-                "timestamp is too large to set as a file time"
+                "timestamp is too large to set as a file time",
             )),
             Some(_) => Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
-                "timestamp is too small to set as a file time"
+                "timestamp is too small to set as a file time",
             )),
             None => Ok(libc::timespec { tv_sec: 0, tv_nsec: libc::UTIME_OMIT as _ }),
         };

library/std/src/sys/pal/unix/os.rs

@@ -260,7 +260,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
 
     let exe_path = env::args().next().ok_or(io::const_error!(
         ErrorKind::NotFound,
-        "an executable path was not found because no arguments were provided through argv"
+        "an executable path was not found because no arguments were provided through argv",
     ))?;
     let path = PathBuf::from(exe_path);
     if path.is_absolute() {
@@ -382,9 +382,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
         cvt(libc::sysctl(mib, 4, argv.as_mut_ptr() as *mut _, &mut argv_len, ptr::null_mut(), 0))?;
         argv.set_len(argv_len as usize);
         if argv[0].is_null() {
-            return Err(
+            return Err(io::const_error!(io::ErrorKind::Uncategorized, "no current exe available"));
-                io::const_error!(io::ErrorKind::Uncategorized, "no current exe available",),
-            );
         }
         let argv0 = CStr::from_ptr(argv[0]).to_bytes();
         if argv0[0] == b'.' || argv0.iter().any(|b| *b == b'/') {
@@ -526,7 +524,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
 
     let exe_path = env::args().next().ok_or(io::const_error!(
         ErrorKind::Uncategorized,
-        "an executable path was not found because no arguments were provided through argv"
+        "an executable path was not found because no arguments were provided through argv",
     ))?;
     let path = PathBuf::from(exe_path);
 

library/std/src/sys/pal/unix/process/process_unix.rs

@@ -228,7 +228,7 @@ impl Command {
         let envp = self.capture_env();
 
         if self.saw_nul() {
-            return io::const_error!(ErrorKind::InvalidInput, "nul byte found in provided data",);
+            return io::const_error!(ErrorKind::InvalidInput, "nul byte found in provided data");
         }
 
         match self.setup_io(default, true) {
@@ -1228,7 +1228,7 @@ mod linux_child_ext {
                 .as_ref()
                 // SAFETY: The os type is a transparent wrapper, therefore we can transmute references
                 .map(|fd| unsafe { mem::transmute::<&imp::PidFd, &os::PidFd>(fd) })
-                .ok_or_else(|| io::Error::new(ErrorKind::Uncategorized, "No pidfd was created."))
+                .ok_or_else(|| io::const_error!(ErrorKind::Uncategorized, "No pidfd was created."))
         }
 
         fn into_pidfd(mut self) -> Result<os::PidFd, Self> {

library/std/src/sys/pal/wasi/fs.rs

@@ -533,7 +533,7 @@ impl File {
             Some(time) if let Some(ts) = time.to_wasi_timestamp() => Ok(ts),
             Some(_) => Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
-                "timestamp is too large to set as a file time"
+                "timestamp is too large to set as a file time",
             )),
             None => Ok(0),
         };
@@ -773,8 +773,7 @@ fn open_parent(p: &Path) -> io::Result<(ManuallyDrop<WasiFd>, PathBuf)> {
                     }
                     let msg = format!(
                         "failed to find a pre-opened file descriptor \
-                     through which {:?} could be opened",
+                        through which {p:?} could be opened",
-                        p
                     );
                     return Err(io::Error::new(io::ErrorKind::Uncategorized, msg));
                 }

library/std/src/sys/pal/windows/fs.rs

@@ -1468,9 +1468,7 @@ pub fn link(original: &Path, link: &Path) -> io::Result<()> {
 
 #[cfg(target_vendor = "uwp")]
 pub fn link(_original: &Path, _link: &Path) -> io::Result<()> {
-    return Err(
+    return Err(io::const_error!(io::ErrorKind::Unsupported, "hard link are not supported on UWP"));
-        io::const_error!(io::ErrorKind::Unsupported, "hard link are not supported on UWP",),
-    );
 }
 
 pub fn stat(path: &Path) -> io::Result<FileAttr> {

library/std/src/sys/pal/windows/process.rs

@@ -435,9 +435,7 @@ fn resolve_exe<'a>(
 ) -> io::Result<Vec<u16>> {
     // Early return if there is no filename.
     if exe_path.is_empty() || path::has_trailing_slash(exe_path) {
-        return Err(
+        return Err(io::const_error!(io::ErrorKind::InvalidInput, "program path has no file name"));
-            io::const_error!(io::ErrorKind::InvalidInput, "program path has no file name",),
-        );
     }
     // Test if the file name has the `exe` extension.
     // This does a case-insensitive `ends_with`.

library/test/src/formatters/junit.rs

@@ -39,15 +39,15 @@ fn str_to_cdata(s: &str) -> String {
 
 impl<T: Write> OutputFormatter for JunitFormatter<T> {
     fn write_discovery_start(&mut self) -> io::Result<()> {
-        Err(io::Error::new(io::ErrorKind::NotFound, "Not yet implemented!"))
+        Err(io::const_error!(io::ErrorKind::NotFound, "Not yet implemented!"))
     }
 
     fn write_test_discovered(&mut self, _desc: &TestDesc, _test_type: &str) -> io::Result<()> {
-        Err(io::Error::new(io::ErrorKind::NotFound, "Not yet implemented!"))
+        Err(io::const_error!(io::ErrorKind::NotFound, "Not yet implemented!"))
     }
 
     fn write_discovery_finish(&mut self, _state: &ConsoleTestDiscoveryState) -> io::Result<()> {
-        Err(io::Error::new(io::ErrorKind::NotFound, "Not yet implemented!"))
+        Err(io::const_error!(io::ErrorKind::NotFound, "Not yet implemented!"))
     }
 
     fn write_run_start(

library/test/src/lib.rs

@@ -20,6 +20,7 @@
 #![feature(rustdoc_internals)]
 #![feature(file_buffered)]
 #![feature(internal_output_capture)]
+#![feature(io_const_error)]
 #![feature(staged_api)]
 #![feature(process_exitcode_internals)]
 #![feature(panic_can_unwind)]

library/test/src/term/terminfo/mod.rs

@@ -90,7 +90,7 @@ impl TermInfo {
 
         get_dbpath_for_term(name)
             .ok_or_else(|| {
-                Error::IoError(io::Error::new(io::ErrorKind::NotFound, "terminfo file not found"))
+                Error::IoError(io::const_error!(io::ErrorKind::NotFound, "terminfo file not found"))
             })
             .and_then(|p| TermInfo::from_path(&(*p)))
     }

library/test/src/term/terminfo/parser/compiled.rs

@@ -173,7 +173,7 @@ fn read_le_u32(r: &mut dyn io::Read) -> io::Result<u32> {
 fn read_byte(r: &mut dyn io::Read) -> io::Result<u8> {
     match r.bytes().next() {
         Some(s) => s,
-        None => Err(io::Error::new(io::ErrorKind::Other, "end of file")),
+        None => Err(io::const_error!(io::ErrorKind::Other, "end of file")),
     }
 }