vxWorks: set DEFAULT_MIN_STACK_SIZE to 256K and use min_stack to pass initial stack size to rtpSpawn

src/libstd/sys/vxworks/fast_thread_local.rs

@@ -1,5 +1,3 @@
-// Copyright (c) 2019 Wind River Systems, Inc.
-
 #![cfg(target_thread_local)]
 #![unstable(feature = "thread_local_internals", issue = "0")]
 

src/libstd/sys/vxworks/process/process_vxworks.rs

@@ -5,6 +5,7 @@ use crate::sys;
 use crate::sys::cvt;
 use crate::sys::process::rtp;
 use crate::sys::process::process_common::*;
+use crate::sys_common::thread;
 
 ////////////////////////////////////////////////////////////////////////////////
 // Command
@@ -57,8 +58,7 @@ impl Command {
                 self.get_argv().as_ptr() as *const _, // argv
                 *sys::os::environ() as *const *const c_char,
                 100 as c_int,                         // initial priority
-                0x16000,                                    // initial stack size. 0 defaults
-                                                      // to 0x4000 in 32 bit and 0x8000 in 64 bit
+                thread::min_stack(),                  // initial stack size.
                 0,                                    // options
                 0                                     // task options
             );

src/libstd/sys/vxworks/thread.rs

@@ -8,7 +8,7 @@ use crate::time::Duration;
 
 use crate::sys_common::thread::*;
 
-pub const DEFAULT_MIN_STACK_SIZE: usize = 2 * 1024 * 1024;
+pub const DEFAULT_MIN_STACK_SIZE: usize = 0x40000; // 256K
 
 pub struct Thread {
     id: libc::pthread_t,