Auto merge of #1521 - Wind-River:master_rebase, r=gnzlbg

Fix building error at backtrace

I get this error when builind backtrace:

error[E0308]: mismatched types
  --> /folk/prj-rust-dev/bpang/ala-diab-pb19l/fix_bugs/latest/.cargo/git/checkouts/backtrace-rs-fb1f822361417489/e745627/src/symboli\
ze/dladdr.rs:38:73
   |
38 |                         Some(SymbolName::new(slice::from_raw_parts(ptr, len)))
   |                                                                         ^^^ expected usize, found u64
help: you can convert an `u64` to `usize` and panic if the converted value wouldn't fit

It shows the 'size_t' is expected to be defined as "usize".

Author: bors

src/vxworks/mod.rs

@@ -25,23 +25,11 @@ pub type c_ulonglong = u64;
 pub type intmax_t = i64;
 pub type uintmax_t = u64;
 
-cfg_if! {
-    if #[cfg(target_pointer_width = "32")] {
-        pub type size_t = c_uint;
-        pub type ssize_t = c_int;
-        pub type ptrdiff_t = c_int;
-        pub type intptr_t = c_int;
-        pub type uintptr_t = c_uint;
-    } else if #[cfg(target_pointer_width = "64")] {
-        pub type size_t = c_ulonglong;
-        pub type ssize_t = c_longlong;
-        pub type ptrdiff_t = c_longlong;
-        pub type intptr_t = c_longlong;
-        pub type uintptr_t = c_ulonglong;
-    } else {
-        // Unknown target_pointer_width
-    }
-}
+pub type uintptr_t = usize;
+pub type intptr_t = isize;
+pub type ptrdiff_t = isize;
+pub type size_t = ::uintptr_t;
+pub type ssize_t = ::intptr_t;
 
 pub type pid_t = i32;
 pub type in_addr_t = u32;