Make drop glue use new symbol naming scheme.

Author: michaelwoerister

src/librustc_trans/back/symbol_names.rs

@@ -96,7 +96,7 @@
 //! virtually impossible. Thus, symbol hash generation exclusively relies on
 //! DefPaths which are much more robust in the face of changes to the code base.
 
-use trans::CrateContext;
+use trans::{CrateContext, gensym_name};
 use util::sha2::{Digest, Sha256};
 
 use rustc::middle::cstore;
@@ -222,3 +222,15 @@ pub fn exported_name_with_suffix<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
                                            -> String {
    exported_name_with_opt_suffix(ccx, def_id, parameters, Some(suffix))
 }
+
+/// Only symbols that are invisible outside their compilation unit should use a
+/// name generated by this function.
+pub fn internal_name_from_type_and_suffix<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
+                                                    t: ty::Ty<'tcx>,
+                                                    suffix: &str)
+                                                    -> String {
+    let path = [token::intern(&t.to_string()).as_str(),
+                gensym_name(suffix).as_str()];
+    let hash = get_symbol_hash(ccx, &Vec::new(), cstore::LOCAL_CRATE, &[t]);
+    link::mangle(path.iter().cloned(), Some(&hash[..]))
+}

src/librustc_trans/trans/glue.rs

@@ -14,7 +14,7 @@
 
 use std;
 
-use back::link::*;
+use back::symbol_names;
 use llvm;
 use llvm::{ValueRef, get_param};
 use middle::lang_items::ExchangeFreeFnLangItem;
@@ -256,7 +256,12 @@ fn get_drop_glue_core<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
         return llfn;
     };
 
-    let fn_nm = mangle_internal_name_by_type_and_seq(ccx, t, "drop");
+    let suffix = match g {
+        DropGlueKind::Ty(_) => "drop",
+        DropGlueKind::TyContents(_) => "drop_contents",
+    };
+
+    let fn_nm = symbol_names::internal_name_from_type_and_suffix(ccx, t, suffix);
     let llfn = declare::define_cfn(ccx, &fn_nm, llfnty, ccx.tcx().mk_nil()).unwrap_or_else(||{
        ccx.sess().bug(&format!("symbol `{}` already defined", fn_nm));
     });