rt: Remove rust_exchange_alloc

Author: brson

mk/rt.mk

@@ -75,7 +75,6 @@ RUNTIME_CXXS_$(1)_$(2) := \
               rt/rust_gc_metadata.cpp \
               rt/rust_util.cpp \
               rt/rust_log.cpp \
-              rt/rust_exchange_alloc.cpp \
               rt/isaac/randport.cpp \
               rt/miniz.cpp \
               rt/rust_abi.cpp \

src/rt/rust_exchange_alloc.cpp

@@ -12,7 +12,6 @@
 #define RUST_UTIL_H
 
 #include <limits.h>
-#include "rust_exchange_alloc.h"
 #include "rust_type.h"
 
 extern struct type_desc str_body_tydesc;
@@ -57,16 +56,6 @@ vec_data(rust_vec *v) {
     return reinterpret_cast<T*>(v->data);
 }
 
-inline void reserve_vec_exact(rust_vec** vpp,
-                              size_t size) {
-    if (size > (*vpp)->alloc) {
-        rust_exchange_alloc exchange_alloc;
-        *vpp = (rust_vec*)exchange_alloc
-            .realloc(*vpp, size + sizeof(rust_vec));
-        (*vpp)->alloc = size;
-    }
-}
-
 typedef rust_vec rust_str;
 
 inline size_t get_box_size(size_t body_size, size_t body_align) {