Fix wrapping memory reads for 64-bit addresses

src/gdbserver.rs

@@ -280,17 +280,18 @@ impl GdbConnection {
             }
         } else if let Some(op) = req.match_some_str(["m", "x"]) {
             let mut read_memory = || {
-                let start = req.match_hex::<u32>()?;
+                let start = req.match_hex::<u64>()? as u32;
                 if !req.match_str(",") {
                     return None;
                 };
-                let size = req.match_hex::<u32>()?;
+                let length = req.match_hex::<usize>()?;
                 let mut buf = self.memory_buf.take().unwrap_or_default();
                 buf.clear();
                 let (tx, rx) = ::oneshot::channel();
                 self.client.send_command(EmulatorCommand::ReadMemory(
                     self.sim_id,
-                    start..(start + size),
+                    start,
+                    length,
                     buf,
                     tx,
                 ));