libcore: Fix more merge fallout.

3 files changed, 29 insertions, 5 deletions

diff --git a/src/libsyntax/ext/build.rs b/src/libsyntax/ext/build.rs
index c1163fda844..3097cb799a2 100644
--- a/src/libsyntax/ext/build.rs
+++ b/src/libsyntax/ext/build.rs
@@ -11,6 +11,7 @@
 use ast;
 use codemap;
 use codemap::span;
+use fold;
 use ext::base::ext_ctxt;
 use ext::build;
 
@@ -516,3 +517,20 @@ pub fn mk_unreachable(cx: @ext_ctxt, span: span) -> @ast::expr {
 pub fn mk_unreachable_arm(cx: @ext_ctxt, span: span) -> ast::arm {
     mk_arm(cx, span, ~[mk_pat_wild(cx, span)], mk_unreachable(cx, span))
 }
+
+//
+// Duplication functions
+//
+// These functions just duplicate AST nodes.
+//
+
+pub fn duplicate_expr(cx: @ext_ctxt, expr: @ast::expr) -> @ast::expr {
+    let folder = fold::default_ast_fold();
+    let folder = @fold::AstFoldFns {
+        new_id: |_| cx.next_id(),
+        ..*folder
+    };
+    let folder = fold::make_fold(folder);
+    folder.fold_expr(expr)
+}
+
diff --git a/src/libsyntax/ext/deriving/rand.rs b/src/libsyntax/ext/deriving/rand.rs
index 03202801d20..604686f442f 100644
--- a/src/libsyntax/ext/deriving/rand.rs
+++ b/src/libsyntax/ext/deriving/rand.rs
@@ -35,7 +35,7 @@ pub fn expand_deriving_rand(cx: @ext_ctxt,
                 self_ty: None,
                 args: ~[
                     Ptr(~Literal(Path::new_local(~"R")),
-                        Borrowed(None, ast::m_imm))
+                        Borrowed(None, ast::m_mutbl))
                 ],
                 ret_ty: Self,
                 const_nonmatching: false,
@@ -59,8 +59,10 @@ fn rand_substructure(cx: @ext_ctxt, span: span, substr: &Substructure) -> @expr
         cx.ident_of(~"rand")
     ];
     let rand_call = || {
-        build::mk_call_global(cx, span,
-                              copy rand_ident, copy rng)
+        build::mk_call_global(cx,
+                              span,
+                              copy rand_ident,
+                              ~[ build::duplicate_expr(cx, rng[0]) ])
     };
 
     return match *substr.fields {
@@ -80,7 +82,10 @@ fn rand_substructure(cx: @ext_ctxt, span: span, substr: &Substructure) -> @expr
             let rand_name = build::mk_raw_path_(span, copy rand_ident, None, ~[ u32_ty, r_ty ]);
             let rand_name = build::mk_path_raw(cx, span, rand_name);
 
-            let rv_call = build::mk_call_(cx, span, rand_name, copy rng);
+            let rv_call = build::mk_call_(cx,
+                                          span,
+                                          rand_name,
+                                          ~[ build::duplicate_expr(cx, rng[0]) ]);
 
             // rand() % variants.len()
             let rand_variant = build::mk_binary(cx, span, ast::rem,
@@ -133,4 +138,4 @@ fn rand_substructure(cx: @ext_ctxt, span: span, substr: &Substructure) -> @expr
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index 229a8664d0c..d181dd87e38 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -859,3 +859,4 @@ impl AstFoldExtensions for @ast_fold {
 pub fn make_fold(afp: ast_fold_fns) -> @ast_fold {
     afp as @ast_fold
 }
+