From 03ef71e262a8d48ba10abf9181490dc5c87c7fc3 Mon Sep 17 00:00:00 2001
From: Kevin Ballard <kevin@sb.org>
Date: Wed, 14 Aug 2013 19:21:59 -0700
Subject: [PATCH] Add ToCStr method .with_c_str()

.with_c_str() is a replacement for the old .as_c_str(), to avoid
unnecessary boilerplate.

Replace all usages of .to_c_str().with_ref() with .with_c_str().
---
 src/libextra/rl.rs                           | 10 ++--
 src/librustc/back/link.rs                    | 22 ++++-----
 src/librustc/back/passes.rs                  |  2 +-
 src/librustc/lib/llvm.rs                     |  2 +-
 src/librustc/metadata/loader.rs              |  2 +-
 src/librustc/middle/trans/asm.rs             |  4 +-
 src/librustc/middle/trans/base.rs            | 42 ++++++++---------
 src/librustc/middle/trans/builder.rs         |  6 +--
 src/librustc/middle/trans/common.rs          |  6 +--
 src/librustc/middle/trans/consts.rs          |  4 +-
 src/librustc/middle/trans/context.rs         |  6 +--
 src/librustc/middle/trans/controlflow.rs     |  2 +-
 src/librustc/middle/trans/debuginfo.rs       | 40 ++++++++--------
 src/librustc/middle/trans/expr.rs            |  2 +-
 src/librustc/middle/trans/glue.rs            |  2 +-
 src/librustc/middle/trans/meth.rs            |  2 +-
 src/librustc/middle/trans/type_.rs           |  2 +-
 src/librustpkg/util.rs                       |  4 +-
 src/libstd/c_str.rs                          | 23 ++++++++++
 src/libstd/io.rs                             | 10 ++--
 src/libstd/os.rs                             | 48 ++++++++++----------
 src/libstd/path.rs                           |  6 +--
 src/libstd/ptr.rs                            |  8 ++--
 src/libstd/rt/borrowck.rs                    |  6 +--
 src/libstd/rt/logging.rs                     |  2 +-
 src/libstd/rt/uv/uvio.rs                     |  4 +-
 src/libstd/rt/uv/uvll.rs                     |  4 +-
 src/libstd/run.rs                            |  4 +-
 src/libstd/sys.rs                            |  8 ++--
 src/libstd/unstable/dynamic_lib.rs           |  4 +-
 src/libstd/unstable/lang.rs                  |  2 +-
 src/test/run-pass/c-stack-returning-int64.rs |  4 +-
 src/test/run-pass/foreign-fn-linkname.rs     |  2 +-
 33 files changed, 159 insertions(+), 136 deletions(-)

diff --git a/src/libextra/rl.rs b/src/libextra/rl.rs
index 9106d4cd684..ead1f276ca7 100644
--- a/src/libextra/rl.rs
+++ b/src/libextra/rl.rs
@@ -32,7 +32,7 @@ pub mod rustrt {
 
 /// Add a line to history
 pub unsafe fn add_history(line: &str) -> bool {
-    do line.to_c_str().with_ref |buf| {
+    do line.with_c_str |buf| {
         rustrt::linenoiseHistoryAdd(buf) == 1 as c_int
     }
 }
@@ -44,21 +44,21 @@ pub unsafe fn set_history_max_len(len: int) -> bool {
 
 /// Save line history to a file
 pub unsafe fn save_history(file: &str) -> bool {
-    do file.to_c_str().with_ref |buf| {
+    do file.with_c_str |buf| {
         rustrt::linenoiseHistorySave(buf) == 1 as c_int
     }
 }
 
 /// Load line history from a file
 pub unsafe fn load_history(file: &str) -> bool {
-    do file.to_c_str().with_ref |buf| {
+    do file.with_c_str |buf| {
         rustrt::linenoiseHistoryLoad(buf) == 1 as c_int
     }
 }
 
 /// Print out a prompt and then wait for input and return it
 pub unsafe fn read(prompt: &str) -> Option<~str> {
-    do prompt.to_c_str().with_ref |buf| {
+    do prompt.with_c_str |buf| {
         let line = rustrt::linenoise(buf);
 
         if line.is_null() { None }
@@ -80,7 +80,7 @@ pub unsafe fn complete(cb: CompletionCb) {
 
             unsafe {
                 do cb(str::raw::from_c_str(line)) |suggestion| {
-                    do suggestion.to_c_str().with_ref |buf| {
+                    do suggestion.with_c_str |buf| {
                         rustrt::linenoiseAddCompletion(completions, buf);
                     }
                 }
diff --git a/src/librustc/back/link.rs b/src/librustc/back/link.rs
index ed6eab5de19..91b6ee24110 100644
--- a/src/librustc/back/link.rs
+++ b/src/librustc/back/link.rs
@@ -78,10 +78,10 @@ pub fn WriteOutputFile(sess: Session,
         OptLevel: c_int,
         EnableSegmentedStacks: bool) {
     unsafe {
-        do Triple.to_c_str().with_ref |Triple| {
-            do Cpu.to_c_str().with_ref |Cpu| {
-                do Feature.to_c_str().with_ref |Feature| {
-                    do Output.to_c_str().with_ref |Output| {
+        do Triple.with_c_str |Triple| {
+            do Cpu.with_c_str |Cpu| {
+                do Feature.with_c_str |Feature| {
+                    do Output.with_c_str |Output| {
                         let result = llvm::LLVMRustWriteOutputFile(
                                 PM,
                                 M,
@@ -152,7 +152,7 @@ pub fn exec(sess: Session,
 
                 debug!("linking: %s", path);
 
-                do path.to_c_str().with_ref |buf_t| {
+                do path.with_c_str |buf_t| {
                     if !llvm::LLVMRustLoadCrate(manager, buf_t) {
                         llvm_err(sess, ~"Could not link");
                     }
@@ -171,7 +171,7 @@ pub fn exec(sess: Session,
             // Next, we need to get a handle on the _rust_main function by
             // looking up it's corresponding ValueRef and then requesting that
             // the execution engine compiles the function.
-            let fun = do "_rust_main".to_c_str().with_ref |entry| {
+            let fun = do "_rust_main".with_c_str |entry| {
                 llvm::LLVMGetNamedFunction(m, entry)
             };
             if fun.is_null() {
@@ -270,14 +270,14 @@ pub fn run_passes(sess: Session,
                   output_type_bitcode => {
                     if opts.optimize != session::No {
                         let filename = output.with_filetype("no-opt.bc");
-                        do filename.to_c_str().with_ref |buf| {
+                        do filename.with_c_str |buf| {
                             llvm::LLVMWriteBitcodeToFile(llmod, buf);
                         }
                     }
                   }
                   _ => {
                     let filename = output.with_filetype("bc");
-                    do filename.to_c_str().with_ref |buf| {
+                    do filename.with_c_str |buf| {
                         llvm::LLVMWriteBitcodeToFile(llmod, buf);
                     }
                   }
@@ -340,7 +340,7 @@ pub fn run_passes(sess: Session,
                     // Always output the bitcode file with --save-temps
 
                     let filename = output.with_filetype("opt.bc");
-                    do filename.to_c_str().with_ref |buf| {
+                    do filename.with_c_str |buf| {
                         llvm::LLVMWriteBitcodeToFile(llmod, buf)
                     };
                     // Save the assembly file if -S is used
@@ -401,13 +401,13 @@ pub fn run_passes(sess: Session,
 
             if output_type == output_type_llvm_assembly {
                 // Given options "-S --emit-llvm": output LLVM assembly
-                do output.to_c_str().with_ref |buf_o| {
+                do output.with_c_str |buf_o| {
                     llvm::LLVMRustAddPrintModulePass(pm.llpm, llmod, buf_o);
                 }
             } else {
                 // If only a bitcode file is asked for by using the
                 // '--emit-llvm' flag, then output it here
-                do output.to_c_str().with_ref |buf| {
+                do output.with_c_str |buf| {
                     llvm::LLVMWriteBitcodeToFile(llmod, buf);
                 }
             }
diff --git a/src/librustc/back/passes.rs b/src/librustc/back/passes.rs
index 854d11fd350..29bc577dff9 100644
--- a/src/librustc/back/passes.rs
+++ b/src/librustc/back/passes.rs
@@ -173,7 +173,7 @@ pub fn populate_pass_manager(sess: Session, pm: &mut PassManager, pass_list:&[~s
 }
 
 pub fn create_pass(name:&str) -> Option<PassRef> {
-    do name.to_c_str().with_ref |s| {
+    do name.with_c_str |s| {
         unsafe {
             let p = llvm::LLVMCreatePass(s);
             if p.is_null() {
diff --git a/src/librustc/lib/llvm.rs b/src/librustc/lib/llvm.rs
index 156aafacfec..307b691a56e 100644
--- a/src/librustc/lib/llvm.rs
+++ b/src/librustc/lib/llvm.rs
@@ -2271,7 +2271,7 @@ pub struct TargetData {
 }
 
 pub fn mk_target_data(string_rep: &str) -> TargetData {
-    let lltd = do string_rep.to_c_str().with_ref |buf| {
+    let lltd = do string_rep.with_c_str |buf| {
         unsafe { llvm::LLVMCreateTargetData(buf) }
     };
 
diff --git a/src/librustc/metadata/loader.rs b/src/librustc/metadata/loader.rs
index 554cdf4b2b4..d0060931a66 100644
--- a/src/librustc/metadata/loader.rs
+++ b/src/librustc/metadata/loader.rs
@@ -199,7 +199,7 @@ pub fn metadata_matches(extern_metas: &[@ast::MetaItem],
 fn get_metadata_section(os: os,
                         filename: &Path) -> Option<@~[u8]> {
     unsafe {
-        let mb = do filename.to_c_str().with_ref |buf| {
+        let mb = do filename.with_c_str |buf| {
             llvm::LLVMRustCreateMemoryBufferWithContentsOfFile(buf)
         };
         if mb as int == 0 { return option::None::<@~[u8]>; }
diff --git a/src/librustc/middle/trans/asm.rs b/src/librustc/middle/trans/asm.rs
index b6057199a28..3400da75b9e 100644
--- a/src/librustc/middle/trans/asm.rs
+++ b/src/librustc/middle/trans/asm.rs
@@ -120,8 +120,8 @@ pub fn trans_inline_asm(bcx: @mut Block, ia: &ast::inline_asm) -> @mut Block {
         ast::asm_intel => lib::llvm::AD_Intel
     };
 
-    let r = do ia.asm.to_c_str().with_ref |a| {
-        do constraints.to_c_str().with_ref |c| {
+    let r = do ia.asm.with_c_str |a| {
+        do constraints.with_c_str |c| {
             InlineAsmCall(bcx, a, c, inputs, output, ia.volatile, ia.alignstack, dialect)
         }
     };
diff --git a/src/librustc/middle/trans/base.rs b/src/librustc/middle/trans/base.rs
index eedc97440f0..3236e754be8 100644
--- a/src/librustc/middle/trans/base.rs
+++ b/src/librustc/middle/trans/base.rs
@@ -181,7 +181,7 @@ fn drop(&self) {
 }
 
 pub fn decl_fn(llmod: ModuleRef, name: &str, cc: lib::llvm::CallConv, ty: Type) -> ValueRef {
-    let llfn: ValueRef = do name.to_c_str().with_ref |buf| {
+    let llfn: ValueRef = do name.with_c_str |buf| {
         unsafe {
             llvm::LLVMGetOrInsertFunction(llmod, buf, ty.to_ref())
         }
@@ -221,7 +221,7 @@ pub fn get_extern_const(externs: &mut ExternMap, llmod: ModuleRef,
         None => ()
     }
     unsafe {
-        let c = do name.to_c_str().with_ref |buf| {
+        let c = do name.with_c_str |buf| {
             llvm::LLVMAddGlobal(llmod, ty.to_ref(), buf)
         };
         externs.insert(name, c);
@@ -523,7 +523,7 @@ pub fn get_res_dtor(ccx: @mut CrateContext,
 // Structural comparison: a rather involved form of glue.
 pub fn maybe_name_value(cx: &CrateContext, v: ValueRef, s: &str) {
     if cx.sess.opts.save_temps {
-        do s.to_c_str().with_ref |buf| {
+        do s.with_c_str |buf| {
             unsafe {
                 llvm::LLVMSetValueName(v, buf)
             }
@@ -1136,7 +1136,7 @@ pub fn new_block(cx: @mut FunctionContext,
                  opt_node_info: Option<NodeInfo>)
               -> @mut Block {
     unsafe {
-        let llbb = do name.to_c_str().with_ref |buf| {
+        let llbb = do name.with_c_str |buf| {
             llvm::LLVMAppendBasicBlockInContext(cx.ccx.llcx, cx.llfn, buf)
         };
         let bcx = @mut Block::new(llbb,
@@ -1553,7 +1553,7 @@ pub struct BasicBlocks {
 pub fn mk_staticallocas_basic_block(llfn: ValueRef) -> BasicBlockRef {
     unsafe {
         let cx = task_llcx();
-        do "static_allocas".to_c_str().with_ref | buf| {
+        do "static_allocas".with_c_str | buf| {
             llvm::LLVMAppendBasicBlockInContext(cx, llfn, buf)
         }
     }
@@ -1562,7 +1562,7 @@ pub fn mk_staticallocas_basic_block(llfn: ValueRef) -> BasicBlockRef {
 pub fn mk_return_basic_block(llfn: ValueRef) -> BasicBlockRef {
     unsafe {
         let cx = task_llcx();
-        do "return".to_c_str().with_ref |buf| {
+        do "return".with_c_str |buf| {
             llvm::LLVMAppendBasicBlockInContext(cx, llfn, buf)
         }
     }
@@ -2332,7 +2332,7 @@ fn create_entry_fn(ccx: @mut CrateContext,
             };
             decl_cdecl_fn(ccx.llmod, main_name, llfty)
         };
-        let llbb = do "top".to_c_str().with_ref |buf| {
+        let llbb = do "top".with_c_str |buf| {
             unsafe {
                 llvm::LLVMAppendBasicBlockInContext(ccx.llcx, llfn, buf)
             }
@@ -2342,7 +2342,7 @@ fn create_entry_fn(ccx: @mut CrateContext,
             llvm::LLVMPositionBuilderAtEnd(bld, llbb);
 
             let crate_map = ccx.crate_map;
-            let opaque_crate_map = do "crate_map".to_c_str().with_ref |buf| {
+            let opaque_crate_map = do "crate_map".with_c_str |buf| {
                 llvm::LLVMBuildPointerCast(bld, crate_map, Type::i8p().to_ref(), buf)
             };
 
@@ -2360,7 +2360,7 @@ fn create_entry_fn(ccx: @mut CrateContext,
                 };
 
                 let args = {
-                    let opaque_rust_main = do "rust_main".to_c_str().with_ref |buf| {
+                    let opaque_rust_main = do "rust_main".with_c_str |buf| {
                         llvm::LLVMBuildPointerCast(bld, rust_main, Type::i8p().to_ref(), buf)
                     };
 
@@ -2442,7 +2442,7 @@ pub fn get_item_val(ccx: @mut CrateContext, id: ast::NodeId) -> ValueRef {
 
                             unsafe {
                                 let llty = llvm::LLVMTypeOf(v);
-                                let g = do sym.to_c_str().with_ref |buf| {
+                                let g = do sym.with_c_str |buf| {
                                     llvm::LLVMAddGlobal(ccx.llmod, llty, buf)
                                 };
 
@@ -2475,7 +2475,7 @@ pub fn get_item_val(ccx: @mut CrateContext, id: ast::NodeId) -> ValueRef {
 
                     match (attr::first_attr_value_str_by_name(i.attrs, "link_section")) {
                         Some(sect) => unsafe {
-                            do sect.to_c_str().with_ref |buf| {
+                            do sect.with_c_str |buf| {
                                 llvm::LLVMSetSection(v, buf);
                             }
                         },
@@ -2516,7 +2516,7 @@ pub fn get_item_val(ccx: @mut CrateContext, id: ast::NodeId) -> ValueRef {
                         }
                         ast::foreign_item_static(*) => {
                             let ident = token::ident_to_str(&ni.ident);
-                            let g = do ident.to_c_str().with_ref |buf| {
+                            let g = do ident.with_c_str |buf| {
                                 unsafe {
                                     let ty = type_of(ccx, ty);
                                     llvm::LLVMAddGlobal(ccx.llmod, ty.to_ref(), buf)
@@ -2623,7 +2623,7 @@ pub fn trans_constant(ccx: &mut CrateContext, it: @ast::item) {
             let s = mangle_exported_name(ccx, p, ty::mk_int()).to_managed();
             let disr_val = vi[i].disr_val;
             note_unique_llvm_symbol(ccx, s);
-            let discrim_gvar = do s.to_c_str().with_ref |buf| {
+            let discrim_gvar = do s.with_c_str |buf| {
                 unsafe {
                     llvm::LLVMAddGlobal(ccx.llmod, ccx.int_type.to_ref(), buf)
                 }
@@ -2818,7 +2818,7 @@ pub fn decl_gc_metadata(ccx: &mut CrateContext, llmod_id: &str) {
     }
 
     let gc_metadata_name = ~"_gc_module_metadata_" + llmod_id;
-    let gc_metadata = do gc_metadata_name.to_c_str().with_ref |buf| {
+    let gc_metadata = do gc_metadata_name.with_c_str |buf| {
         unsafe {
             llvm::LLVMAddGlobal(ccx.llmod, Type::i32().to_ref(), buf)
         }
@@ -2833,7 +2833,7 @@ pub fn decl_gc_metadata(ccx: &mut CrateContext, llmod_id: &str) {
 pub fn create_module_map(ccx: &mut CrateContext) -> ValueRef {
     let elttype = Type::struct_([ccx.int_type, ccx.int_type], false);
     let maptype = Type::array(&elttype, (ccx.module_data.len() + 1) as u64);
-    let map = do "_rust_mod_map".to_c_str().with_ref |buf| {
+    let map = do "_rust_mod_map".with_c_str |buf| {
         unsafe {
             llvm::LLVMAddGlobal(ccx.llmod, maptype.to_ref(), buf)
         }
@@ -2881,7 +2881,7 @@ pub fn decl_crate_map(sess: session::Session, mapmeta: LinkMeta,
     let sym_name = ~"_rust_crate_map_" + mapname;
     let arrtype = Type::array(&int_type, n_subcrates as u64);
     let maptype = Type::struct_([Type::i32(), Type::i8p(), int_type, arrtype], false);
-    let map = do sym_name.to_c_str().with_ref |buf| {
+    let map = do sym_name.with_c_str |buf| {
         unsafe {
             llvm::LLVMAddGlobal(llmod, maptype.to_ref(), buf)
         }
@@ -2900,7 +2900,7 @@ pub fn fill_crate_map(ccx: @mut CrateContext, map: ValueRef) {
                       cdata.name,
                       cstore::get_crate_vers(cstore, i),
                       cstore::get_crate_hash(cstore, i));
-        let cr = do nm.to_c_str().with_ref |buf| {
+        let cr = do nm.with_c_str |buf| {
             unsafe {
                 llvm::LLVMAddGlobal(ccx.llmod, ccx.int_type.to_ref(), buf)
             }
@@ -2963,21 +2963,21 @@ pub fn write_metadata(cx: &mut CrateContext, crate: &ast::Crate) {
     let encode_parms = crate_ctxt_to_encode_parms(cx, encode_inlined_item);
     let llmeta = C_bytes(encoder::encode_metadata(encode_parms, crate));
     let llconst = C_struct([llmeta]);
-    let mut llglobal = do "rust_metadata".to_c_str().with_ref |buf| {
+    let mut llglobal = do "rust_metadata".with_c_str |buf| {
         unsafe {
             llvm::LLVMAddGlobal(cx.llmod, val_ty(llconst).to_ref(), buf)
         }
     };
     unsafe {
         llvm::LLVMSetInitializer(llglobal, llconst);
-        do cx.sess.targ_cfg.target_strs.meta_sect_name.to_c_str().with_ref |buf| {
+        do cx.sess.targ_cfg.target_strs.meta_sect_name.with_c_str |buf| {
             llvm::LLVMSetSection(llglobal, buf)
         };
         lib::llvm::SetLinkage(llglobal, lib::llvm::InternalLinkage);
 
         let t_ptr_i8 = Type::i8p();
         llglobal = llvm::LLVMConstBitCast(llglobal, t_ptr_i8.to_ref());
-        let llvm_used = do "llvm.used".to_c_str().with_ref |buf| {
+        let llvm_used = do "llvm.used".with_c_str |buf| {
             llvm::LLVMAddGlobal(cx.llmod, Type::array(&t_ptr_i8, 1).to_ref(), buf)
         };
         lib::llvm::SetLinkage(llvm_used, lib::llvm::AppendingLinkage);
@@ -2991,7 +2991,7 @@ fn mk_global(ccx: &CrateContext,
              internal: bool)
           -> ValueRef {
     unsafe {
-        let llglobal = do name.to_c_str().with_ref |buf| {
+        let llglobal = do name.with_c_str |buf| {
             llvm::LLVMAddGlobal(ccx.llmod, val_ty(llval).to_ref(), buf)
         };
         llvm::LLVMSetInitializer(llglobal, llval);
diff --git a/src/librustc/middle/trans/builder.rs b/src/librustc/middle/trans/builder.rs
index 5c216b2e143..cba7a225395 100644
--- a/src/librustc/middle/trans/builder.rs
+++ b/src/librustc/middle/trans/builder.rs
@@ -423,7 +423,7 @@ pub fn alloca(&self, ty: Type, name: &str) -> ValueRef {
             if name.is_empty() {
                 llvm::LLVMBuildAlloca(self.llbuilder, ty.to_ref(), noname())
             } else {
-                do name.to_c_str().with_ref |c| {
+                do name.with_c_str |c| {
                     llvm::LLVMBuildAlloca(self.llbuilder, ty.to_ref(), c)
                 }
             }
@@ -739,7 +739,7 @@ pub fn add_comment(&self, text: &str) {
             let sanitized = text.replace("$", "");
             let comment_text = fmt!("# %s", sanitized.replace("\n", "\n\t# "));
             self.count_insn("inlineasm");
-            let asm = do comment_text.to_c_str().with_ref |c| {
+            let asm = do comment_text.with_c_str |c| {
                 unsafe {
                     llvm::LLVMConstInlineAsm(Type::func([], &Type::void()).to_ref(),
                                              c, noname(), False, False)
@@ -895,7 +895,7 @@ pub fn trap(&self) {
             let BB: BasicBlockRef = llvm::LLVMGetInsertBlock(self.llbuilder);
             let FN: ValueRef = llvm::LLVMGetBasicBlockParent(BB);
             let M: ModuleRef = llvm::LLVMGetGlobalParent(FN);
-            let T: ValueRef = do "llvm.trap".to_c_str().with_ref |buf| {
+            let T: ValueRef = do "llvm.trap".with_c_str |buf| {
                 llvm::LLVMGetNamedFunction(M, buf)
             };
             assert!((T as int != 0));
diff --git a/src/librustc/middle/trans/common.rs b/src/librustc/middle/trans/common.rs
index 9aa18bc05f8..c5ffcccdb46 100644
--- a/src/librustc/middle/trans/common.rs
+++ b/src/librustc/middle/trans/common.rs
@@ -712,7 +712,7 @@ pub fn C_integral(t: Type, u: u64, sign_extend: bool) -> ValueRef {
 
 pub fn C_floating(s: &str, t: Type) -> ValueRef {
     unsafe {
-        do s.to_c_str().with_ref |buf| {
+        do s.with_c_str |buf| {
             llvm::LLVMConstRealOfString(t.to_ref(), buf)
         }
     }
@@ -760,12 +760,12 @@ pub fn C_cstr(cx: &mut CrateContext, s: @str) -> ValueRef {
             None => ()
         }
 
-        let sc = do s.to_c_str().with_ref |buf| {
+        let sc = do s.with_c_str |buf| {
             llvm::LLVMConstStringInContext(cx.llcx, buf, s.len() as c_uint, False)
         };
 
         let gsym = token::gensym("str");
-        let g = do fmt!("str%u", gsym).to_c_str().with_ref |buf| {
+        let g = do fmt!("str%u", gsym).with_c_str |buf| {
             llvm::LLVMAddGlobal(cx.llmod, val_ty(sc).to_ref(), buf)
         };
         llvm::LLVMSetInitializer(g, sc);
diff --git a/src/librustc/middle/trans/consts.rs b/src/librustc/middle/trans/consts.rs
index 1992d71427f..9aedf15add0 100644
--- a/src/librustc/middle/trans/consts.rs
+++ b/src/librustc/middle/trans/consts.rs
@@ -102,7 +102,7 @@ pub fn const_vec(cx: @mut CrateContext, e: &ast::expr, es: &[@ast::expr])
 
 fn const_addr_of(cx: &mut CrateContext, cv: ValueRef) -> ValueRef {
     unsafe {
-        let gv = do "const".to_c_str().with_ref |name| {
+        let gv = do "const".with_c_str |name| {
             llvm::LLVMAddGlobal(cx.llmod, val_ty(cv).to_ref(), name)
         };
         llvm::LLVMSetInitializer(gv, cv);
@@ -528,7 +528,7 @@ fn const_expr_unadjusted(cx: @mut CrateContext, e: &ast::expr) -> ValueRef {
               ast::expr_vec(ref es, ast::m_imm) => {
                 let (cv, sz, llunitty) = const_vec(cx, e, *es);
                 let llty = val_ty(cv);
-                let gv = do "const".to_c_str().with_ref |name| {
+                let gv = do "const".with_c_str |name| {
                     llvm::LLVMAddGlobal(cx.llmod, llty.to_ref(), name)
                 };
                 llvm::LLVMSetInitializer(gv, cv);
diff --git a/src/librustc/middle/trans/context.rs b/src/librustc/middle/trans/context.rs
index 187c121bbd3..43008ad7a16 100644
--- a/src/librustc/middle/trans/context.rs
+++ b/src/librustc/middle/trans/context.rs
@@ -128,15 +128,15 @@ pub fn new(sess: session::Session,
         unsafe {
             let llcx = llvm::LLVMContextCreate();
             set_task_llcx(llcx);
-            let llmod = do name.to_c_str().with_ref |buf| {
+            let llmod = do name.with_c_str |buf| {
                 llvm::LLVMModuleCreateWithNameInContext(buf, llcx)
             };
             let data_layout: &str = sess.targ_cfg.target_strs.data_layout;
             let targ_triple: &str = sess.targ_cfg.target_strs.target_triple;
-            do data_layout.to_c_str().with_ref |buf| {
+            do data_layout.with_c_str |buf| {
                 llvm::LLVMSetDataLayout(llmod, buf)
             };
-            do targ_triple.to_c_str().with_ref |buf| {
+            do targ_triple.with_c_str |buf| {
                 llvm::LLVMSetTarget(llmod, buf)
             };
             let targ_cfg = sess.targ_cfg;
diff --git a/src/librustc/middle/trans/controlflow.rs b/src/librustc/middle/trans/controlflow.rs
index 2a3003812fe..bf7eeefd3b2 100644
--- a/src/librustc/middle/trans/controlflow.rs
+++ b/src/librustc/middle/trans/controlflow.rs
@@ -238,7 +238,7 @@ pub fn trans_log(log_ex: &ast::expr,
             ccx, modpath, "loglevel");
         let global;
         unsafe {
-            global = do s.to_c_str().with_ref |buf| {
+            global = do s.with_c_str |buf| {
                 llvm::LLVMAddGlobal(ccx.llmod, Type::i32().to_ref(), buf)
             };
             llvm::LLVMSetGlobalConstant(global, False);
diff --git a/src/librustc/middle/trans/debuginfo.rs b/src/librustc/middle/trans/debuginfo.rs
index 66ff2495c29..d23c009ac15 100644
--- a/src/librustc/middle/trans/debuginfo.rs
+++ b/src/librustc/middle/trans/debuginfo.rs
@@ -207,7 +207,7 @@ pub fn create_argument_metadata(bcx: @mut Block,
             argument_index as c_uint
         };
 
-        let arg_metadata = do name.to_c_str().with_ref |name| {
+        let arg_metadata = do name.with_c_str |name| {
             unsafe {
                 llvm::LLVMDIBuilderCreateLocalVariable(
                     DIB(cx),
@@ -351,8 +351,8 @@ pub fn create_function_metadata(fcx: &mut FunctionContext) -> DISubprogram {
     };
 
     let fn_metadata =
-        do cx.sess.str_of(ident).to_c_str().with_ref |name| {
-        do cx.sess.str_of(ident).to_c_str().with_ref |linkage| {
+        do cx.sess.str_of(ident).with_c_str |name| {
+        do cx.sess.str_of(ident).with_c_str |linkage| {
             unsafe {
                 llvm::LLVMDIBuilderCreateFunction(
                     DIB(cx),
@@ -420,11 +420,11 @@ fn compile_unit_metadata(cx: @mut CrateContext) {
     let work_dir = cx.sess.working_dir.to_str();
     let producer = fmt!("rustc version %s", env!("CFG_VERSION"));
 
-    do crate_name.to_c_str().with_ref |crate_name| {
-    do work_dir.to_c_str().with_ref |work_dir| {
-    do producer.to_c_str().with_ref |producer| {
-    do "".to_c_str().with_ref |flags| {
-    do "".to_c_str().with_ref |split_name| {
+    do crate_name.with_c_str |crate_name| {
+    do work_dir.with_c_str |work_dir| {
+    do producer.with_c_str |producer| {
+    do "".with_c_str |flags| {
+    do "".with_c_str |split_name| {
         unsafe {
             llvm::LLVMDIBuilderCreateCompileUnit(dcx.builder,
                 DW_LANG_RUST as c_uint, crate_name, work_dir, producer,
@@ -449,7 +449,7 @@ fn declare_local(bcx: @mut Block,
     let type_metadata = type_metadata(cx, variable_type, span);
     let scope = scope_metadata(bcx.fcx, node_id, span);
 
-    let var_metadata = do name.to_c_str().with_ref |name| {
+    let var_metadata = do name.with_c_str |name| {
         unsafe {
             llvm::LLVMDIBuilderCreateLocalVariable(
                 DIB(cx),
@@ -501,8 +501,8 @@ fn file_metadata(cx: &mut CrateContext, full_path: &str) -> DIFile {
         };
 
     let file_metadata =
-        do file_name.to_c_str().with_ref |file_name| {
-        do work_dir.to_c_str().with_ref |work_dir| {
+        do file_name.with_c_str |file_name| {
+        do work_dir.with_c_str |work_dir| {
             unsafe {
                 llvm::LLVMDIBuilderCreateFile(DIB(cx), file_name, work_dir)
             }
@@ -566,7 +566,7 @@ fn basic_type_metadata(cx: &mut CrateContext, t: ty::t) -> DIType {
 
     let llvm_type = type_of::type_of(cx, t);
     let (size, align) = size_and_align_of(cx, llvm_type);
-    let ty_metadata = do name.to_c_str().with_ref |name| {
+    let ty_metadata = do name.with_c_str |name| {
         unsafe {
             llvm::LLVMDIBuilderCreateBasicType(
                 DIB(cx),
@@ -587,7 +587,7 @@ fn pointer_type_metadata(cx: &mut CrateContext,
     let pointer_llvm_type = type_of::type_of(cx, pointer_type);
     let (pointer_size, pointer_align) = size_and_align_of(cx, pointer_llvm_type);
     let name = ty_to_str(cx.tcx, pointer_type);
-    let ptr_metadata = do name.to_c_str().with_ref |name| {
+    let ptr_metadata = do name.with_c_str |name| {
         unsafe {
             llvm::LLVMDIBuilderCreatePointerType(
                 DIB(cx),
@@ -681,7 +681,7 @@ fn enum_metadata(cx: &mut CrateContext,
             let name: &str = cx.sess.str_of(v.name);
             let discriminant_value = v.disr_val as c_ulonglong;
 
-            do name.to_c_str().with_ref |name| {
+            do name.with_c_str |name| {
                 unsafe {
                     llvm::LLVMDIBuilderCreateEnumerator(
                         DIB(cx),
@@ -695,7 +695,7 @@ fn enum_metadata(cx: &mut CrateContext,
     let loc = span_start(cx, span);
     let file_metadata = file_metadata(cx, loc.file.name);
 
-    let discriminant_type_metadata = do enum_name.to_c_str().with_ref |enum_name| {
+    let discriminant_type_metadata = do enum_name.with_c_str |enum_name| {
         unsafe {
             llvm::LLVMDIBuilderCreateEnumerationType(
                 DIB(cx),
@@ -732,7 +732,7 @@ fn enum_metadata(cx: &mut CrateContext,
                         Some(discriminant_type_metadata),
                         span);
 
-                    do "".to_c_str().with_ref |name| {
+                    do "".with_c_str |name| {
                         unsafe {
                             llvm::LLVMDIBuilderCreateMemberType(
                                 DIB(cx),
@@ -752,7 +752,7 @@ fn enum_metadata(cx: &mut CrateContext,
             let enum_llvm_type = type_of::type_of(cx, enum_type);
             let (enum_type_size, enum_type_align) = size_and_align_of(cx, enum_llvm_type);
 
-            return do enum_name.to_c_str().with_ref |enum_name| {
+            return do enum_name.with_c_str |enum_name| {
                 unsafe {
                     llvm::LLVMDIBuilderCreateUnionType(
                     DIB(cx),
@@ -836,7 +836,7 @@ fn composite_type_metadata(cx: &mut CrateContext,
             let member_offset = machine::llelement_offset(cx, composite_llvm_type, i);
             let member_name: &str = member_names[i];
 
-            do member_name.to_c_str().with_ref |member_name| {
+            do member_name.with_c_str |member_name| {
                 unsafe {
                     llvm::LLVMDIBuilderCreateMemberType(
                         DIB(cx),
@@ -854,7 +854,7 @@ fn composite_type_metadata(cx: &mut CrateContext,
         })
         .collect();
 
-    return do composite_type_name.to_c_str().with_ref |name| {
+    return do composite_type_name.with_c_str |name| {
         unsafe {
             llvm::LLVMDIBuilderCreateStructType(
                 DIB(cx),
@@ -1080,7 +1080,7 @@ fn unimplemented_type_metadata(cx: &mut CrateContext, t: ty::t) -> DIType {
     debug!("unimplemented_type_metadata: %?", ty::get(t));
 
     let name = ty_to_str(cx.tcx, t);
-    let metadata = do fmt!("NYI<%s>", name).to_c_str().with_ref |name| {
+    let metadata = do fmt!("NYI<%s>", name).with_c_str |name| {
         unsafe {
             llvm::LLVMDIBuilderCreateBasicType(
                 DIB(cx),
diff --git a/src/librustc/middle/trans/expr.rs b/src/librustc/middle/trans/expr.rs
index d56fcb1081f..d3b29d17519 100644
--- a/src/librustc/middle/trans/expr.rs
+++ b/src/librustc/middle/trans/expr.rs
@@ -1031,7 +1031,7 @@ fn get_val(bcx: @mut Block, did: ast::def_id, const_ty: ty::t)
                             let symbol = csearch::get_symbol(
                                 bcx.ccx().sess.cstore,
                                 did);
-                            let llval = do symbol.to_c_str().with_ref |buf| {
+                            let llval = do symbol.with_c_str |buf| {
                                 llvm::LLVMAddGlobal(bcx.ccx().llmod,
                                                     llty.to_ref(),
                                                     buf)
diff --git a/src/librustc/middle/trans/glue.rs b/src/librustc/middle/trans/glue.rs
index 4f894deb1a1..9acc3018046 100644
--- a/src/librustc/middle/trans/glue.rs
+++ b/src/librustc/middle/trans/glue.rs
@@ -673,7 +673,7 @@ pub fn declare_tydesc(ccx: &mut CrateContext, t: ty::t) -> @mut tydesc_info {
     let name = mangle_internal_name_by_type_and_seq(ccx, t, "tydesc").to_managed();
     note_unique_llvm_symbol(ccx, name);
     debug!("+++ declare_tydesc %s %s", ppaux::ty_to_str(ccx.tcx, t), name);
-    let gvar = do name.to_c_str().with_ref |buf| {
+    let gvar = do name.with_c_str |buf| {
         unsafe {
             llvm::LLVMAddGlobal(ccx.llmod, ccx.tydesc_type.to_ref(), buf)
         }
diff --git a/src/librustc/middle/trans/meth.rs b/src/librustc/middle/trans/meth.rs
index f5b2ff75596..9ffbafb706c 100644
--- a/src/librustc/middle/trans/meth.rs
+++ b/src/librustc/middle/trans/meth.rs
@@ -537,7 +537,7 @@ pub fn make_vtable(ccx: &mut CrateContext,
 
         let tbl = C_struct(components);
         let vtable = ccx.sess.str_of(gensym_name("vtable"));
-        let vt_gvar = do vtable.to_c_str().with_ref |buf| {
+        let vt_gvar = do vtable.with_c_str |buf| {
             llvm::LLVMAddGlobal(ccx.llmod, val_ty(tbl).to_ref(), buf)
         };
         llvm::LLVMSetInitializer(vt_gvar, tbl);
diff --git a/src/librustc/middle/trans/type_.rs b/src/librustc/middle/trans/type_.rs
index 8d94a0d10d6..f8f6f7b87ec 100644
--- a/src/librustc/middle/trans/type_.rs
+++ b/src/librustc/middle/trans/type_.rs
@@ -171,7 +171,7 @@ pub fn struct_(els: &[Type], packed: bool) -> Type {
 
     pub fn named_struct(name: &str) -> Type {
         let ctx = base::task_llcx();
-        ty!(name.to_c_str().with_ref(|s| llvm::LLVMStructCreateNamed(ctx, s)))
+        ty!(name.with_c_str(|s| llvm::LLVMStructCreateNamed(ctx, s)))
     }
 
     pub fn empty_struct() -> Type {
diff --git a/src/librustpkg/util.rs b/src/librustpkg/util.rs
index afac9423fba..2cbd18f74f4 100644
--- a/src/librustpkg/util.rs
+++ b/src/librustpkg/util.rs
@@ -398,8 +398,8 @@ pub fn link_exe(src: &Path, dest: &Path) -> bool {
     use std::libc;
 
     unsafe {
-        do src.to_c_str().with_ref |src_buf| {
-            do dest.to_c_str().with_ref |dest_buf| {
+        do src.with_c_str |src_buf| {
+            do dest.with_c_str |dest_buf| {
                 libc::link(src_buf, dest_buf) == 0 as libc::c_int &&
                     libc::chmod(dest_buf, 755) == 0 as libc::c_int
             }
diff --git a/src/libstd/c_str.rs b/src/libstd/c_str.rs
index 5c77aa4a65a..e60e9ca8a74 100644
--- a/src/libstd/c_str.rs
+++ b/src/libstd/c_str.rs
@@ -133,6 +133,29 @@ pub trait ToCStr {
 
     /// Unsafe variant of `to_c_str()` that doesn't check for nulls.
     unsafe fn to_c_str_unchecked(&self) -> CString;
+
+    /// Work with a temporary CString constructed from the receiver.
+    /// The provided `*libc::c_char` will be freed immediately upon return.
+    ///
+    /// # Example
+    ///
+    /// ~~~ {.rust}
+    /// let s = "PATH".with_c_str(|path| libc::getenv(path))
+    /// ~~~
+    ///
+    /// # Failure
+    ///
+    /// Raises the `null_byte` condition if the receiver has an interior null.
+    #[inline]
+    fn with_c_str<T>(&self, f: &fn(*libc::c_char) -> T) -> T {
+        self.to_c_str().with_ref(f)
+    }
+
+    /// Unsafe variant of `with_c_str()` that doesn't check for nulls.
+    #[inline]
+    unsafe fn with_c_str_unchecked<T>(&self, f: &fn(*libc::c_char) -> T) -> T {
+        self.to_c_str_unchecked().with_ref(f)
+    }
 }
 
 impl<'self> ToCStr for &'self str {
diff --git a/src/libstd/io.rs b/src/libstd/io.rs
index 2c18bd272e8..c9e0c4f862d 100644
--- a/src/libstd/io.rs
+++ b/src/libstd/io.rs
@@ -1041,8 +1041,8 @@ pub fn stdin() -> @Reader {
 }
 
 pub fn file_reader(path: &Path) -> Result<@Reader, ~str> {
-    let f = do path.to_c_str().with_ref |pathbuf| {
-        do "rb".to_c_str().with_ref |modebuf| {
+    let f = do path.with_c_str |pathbuf| {
+        do "rb".with_c_str |modebuf| {
             unsafe { libc::fopen(pathbuf, modebuf as *libc::c_char) }
         }
     };
@@ -1291,7 +1291,7 @@ fn wb() -> c_int { O_WRONLY as c_int }
         }
     }
     let fd = unsafe {
-        do path.to_c_str().with_ref |pathbuf| {
+        do path.with_c_str |pathbuf| {
             libc::open(pathbuf, fflags, (S_IRUSR | S_IWUSR) as c_int)
         }
     };
@@ -1574,8 +1574,8 @@ pub fn file_writer(path: &Path, flags: &[FileFlag]) -> Result<@Writer, ~str> {
 // FIXME: fileflags // #2004
 pub fn buffered_file_writer(path: &Path) -> Result<@Writer, ~str> {
     unsafe {
-        let f = do path.to_c_str().with_ref |pathbuf| {
-            do "w".to_c_str().with_ref |modebuf| {
+        let f = do path.with_c_str |pathbuf| {
+            do "w".with_c_str |modebuf| {
                 libc::fopen(pathbuf, modebuf)
             }
         };
diff --git a/src/libstd/os.rs b/src/libstd/os.rs
index c916be79c53..b357489d62f 100644
--- a/src/libstd/os.rs
+++ b/src/libstd/os.rs
@@ -239,7 +239,7 @@ fn env_convert(input: ~[~str]) -> ~[(~str, ~str)] {
 pub fn getenv(n: &str) -> Option<~str> {
     unsafe {
         do with_env_lock {
-            let s = do n.to_c_str().with_ref |buf| {
+            let s = do n.with_c_str |buf| {
                 libc::getenv(buf)
             };
             if s.is_null() {
@@ -274,8 +274,8 @@ pub fn getenv(n: &str) -> Option<~str> {
 pub fn setenv(n: &str, v: &str) {
     unsafe {
         do with_env_lock {
-            do n.to_c_str().with_ref |nbuf| {
-                do v.to_c_str().with_ref |vbuf| {
+            do n.with_c_str |nbuf| {
+                do v.with_c_str |vbuf| {
                     libc::funcs::posix01::unistd::setenv(nbuf, vbuf, 1);
                 }
             }
@@ -306,7 +306,7 @@ pub fn unsetenv(n: &str) {
     fn _unsetenv(n: &str) {
         unsafe {
             do with_env_lock {
-                do n.to_c_str().with_ref |nbuf| {
+                do n.with_c_str |nbuf| {
                     libc::funcs::posix01::unistd::unsetenv(nbuf);
                 }
             }
@@ -328,7 +328,7 @@ fn _unsetenv(n: &str) {
 }
 
 pub fn fdopen(fd: c_int) -> *FILE {
-    do "r".to_c_str().with_ref |modebuf| {
+    do "r".with_c_str |modebuf| {
         unsafe {
             libc::fdopen(fd, modebuf)
         }
@@ -464,7 +464,7 @@ fn load_self() -> Option<~str> {
             let mut path = [0 as c_char, .. TMPBUF_SZ];
 
             do path.as_mut_buf |buf, len| {
-                let len = do "/proc/self/exe".to_c_str().with_ref |proc_self_buf| {
+                let len = do "/proc/self/exe".with_c_str |proc_self_buf| {
                     readlink(proc_self_buf, buf, len as size_t) as uint
                 };
 
@@ -593,7 +593,7 @@ pub fn walk_dir(p: &Path, f: &fn(&Path) -> bool) -> bool {
 /// Indicates whether a path represents a directory
 pub fn path_is_dir(p: &Path) -> bool {
     unsafe {
-        do p.to_c_str().with_ref |buf| {
+        do p.with_c_str |buf| {
             rustrt::rust_path_is_dir(buf) != 0 as c_int
         }
     }
@@ -602,7 +602,7 @@ pub fn path_is_dir(p: &Path) -> bool {
 /// Indicates whether a path exists
 pub fn path_exists(p: &Path) -> bool {
     unsafe {
-        do p.to_c_str().with_ref |buf| {
+        do p.with_c_str |buf| {
             rustrt::rust_path_exists(buf) != 0 as c_int
         }
     }
@@ -645,7 +645,7 @@ fn mkdir(p: &Path, _mode: c_int) -> bool {
 
     #[cfg(unix)]
     fn mkdir(p: &Path, mode: c_int) -> bool {
-        do p.to_c_str().with_ref |buf| {
+        do p.with_c_str |buf| {
             unsafe {
                 libc::mkdir(buf, mode as libc::mode_t) == (0 as c_int)
             }
@@ -697,7 +697,7 @@ unsafe fn get_list(p: &Path) -> ~[~str] {
             let mut strings = ~[];
             debug!("os::list_dir -- BEFORE OPENDIR");
 
-            let dir_ptr = do p.to_c_str().with_ref |buf| {
+            let dir_ptr = do p.with_c_str |buf| {
                 opendir(buf)
             };
 
@@ -819,7 +819,7 @@ fn rmdir(p: &Path) -> bool {
 
     #[cfg(unix)]
     fn rmdir(p: &Path) -> bool {
-        do p.to_c_str().with_ref |buf| {
+        do p.with_c_str |buf| {
             unsafe {
                 libc::rmdir(buf) == (0 as c_int)
             }
@@ -844,7 +844,7 @@ fn chdir(p: &Path) -> bool {
 
     #[cfg(unix)]
     fn chdir(p: &Path) -> bool {
-        do p.to_c_str().with_ref |buf| {
+        do p.with_c_str |buf| {
             unsafe {
                 libc::chdir(buf) == (0 as c_int)
             }
@@ -872,8 +872,8 @@ fn do_copy_file(from: &Path, to: &Path) -> bool {
     #[cfg(unix)]
     fn do_copy_file(from: &Path, to: &Path) -> bool {
         unsafe {
-            let istream = do from.to_c_str().with_ref |fromp| {
-                do "rb".to_c_str().with_ref |modebuf| {
+            let istream = do from.with_c_str |fromp| {
+                do "rb".with_c_str |modebuf| {
                     libc::fopen(fromp, modebuf)
                 }
             };
@@ -884,8 +884,8 @@ fn do_copy_file(from: &Path, to: &Path) -> bool {
             let from_mode = from.get_mode().expect("copy_file: couldn't get permissions \
                                                     for source file");
 
-            let ostream = do to.to_c_str().with_ref |top| {
-                do "w+b".to_c_str().with_ref |modebuf| {
+            let ostream = do to.with_c_str |top| {
+                do "w+b".with_c_str |modebuf| {
                     libc::fopen(top, modebuf)
                 }
             };
@@ -917,7 +917,7 @@ fn do_copy_file(from: &Path, to: &Path) -> bool {
             fclose(ostream);
 
             // Give the new file the old file's permissions
-            if do to.to_c_str().with_ref |to_buf| {
+            if do to.with_c_str |to_buf| {
                 libc::chmod(to_buf, from_mode as libc::mode_t)
             } != 0 {
                 return false; // should be a condition...
@@ -944,7 +944,7 @@ fn unlink(p: &Path) -> bool {
     #[cfg(unix)]
     fn unlink(p: &Path) -> bool {
         unsafe {
-            do p.to_c_str().with_ref |buf| {
+            do p.with_c_str |buf| {
                 libc::unlink(buf) == (0 as c_int)
             }
         }
@@ -1282,7 +1282,7 @@ fn default_glob_t () -> libc::glob_t {
     }
 
     let mut g = default_glob_t();
-    do pattern.to_c_str().with_ref |c_pattern| {
+    do pattern.with_c_str |c_pattern| {
         unsafe { libc::glob(c_pattern, 0, ptr::null(), &mut g) }
     };
     do(|| {
@@ -1929,14 +1929,14 @@ fn copy_file_ok() {
             let out = tempdir.push("out.txt");
 
             /* Write the temp input file */
-            let ostream = do input.to_c_str().with_ref |fromp| {
-                do "w+b".to_c_str().with_ref |modebuf| {
+            let ostream = do input.with_c_str |fromp| {
+                do "w+b".with_c_str |modebuf| {
                     libc::fopen(fromp, modebuf)
                 }
             };
             assert!((ostream as uint != 0u));
             let s = ~"hello";
-            do "hello".to_c_str().with_ref |buf| {
+            do "hello".with_c_str |buf| {
                 let write_len = libc::fwrite(buf as *c_void,
                                              1u as size_t,
                                              (s.len() + 1u) as size_t,
@@ -2013,11 +2013,11 @@ fn lseek_(fd: c_int, size: uint) {
         remove_file(&path);
 
         let fd = unsafe {
-            let fd = do path.to_c_str().with_ref |path| {
+            let fd = do path.with_c_str |path| {
                 open(path, O_CREAT | O_RDWR | O_TRUNC, S_IRUSR | S_IWUSR)
             };
             lseek_(fd, size);
-            do "x".to_c_str().with_ref |x| {
+            do "x".with_c_str |x| {
                 assert!(write(fd, x as *c_void, 1) == 1);
             }
             fd
diff --git a/src/libstd/path.rs b/src/libstd/path.rs
index 7f53ddf6e79..de7658b5710 100644
--- a/src/libstd/path.rs
+++ b/src/libstd/path.rs
@@ -381,7 +381,7 @@ pub fn default_stat() -> libc::stat {
 #[cfg(target_os = "win32")]
 impl WindowsPath {
     pub fn stat(&self) -> Option<libc::stat> {
-        do self.to_c_str().with_ref |buf| {
+        do self.with_c_str |buf| {
             let mut st = stat::arch::default_stat();
             match unsafe { libc::stat(buf, &mut st) } {
                 0 => Some(st),
@@ -415,7 +415,7 @@ pub fn get_mode(&self) -> Option<uint> {
 #[cfg(not(target_os = "win32"))]
 impl PosixPath {
     pub fn stat(&self) -> Option<libc::stat> {
-        do self.to_c_str().with_ref |buf| {
+        do self.with_c_str |buf| {
             let mut st = stat::arch::default_stat();
             match unsafe { libc::stat(buf as *libc::c_char, &mut st) } {
                 0 => Some(st),
@@ -493,7 +493,7 @@ pub fn get_ctime(&self) -> Option<(i64, int)> {
 #[cfg(unix)]
 impl PosixPath {
     pub fn lstat(&self) -> Option<libc::stat> {
-        do self.to_c_str().with_ref |buf| {
+        do self.with_c_str |buf| {
             let mut st = stat::arch::default_stat();
             match unsafe { libc::lstat(buf, &mut st) } {
                 0 => Some(st),
diff --git a/src/libstd/ptr.rs b/src/libstd/ptr.rs
index b13d46d540d..9ea56a2e931 100644
--- a/src/libstd/ptr.rs
+++ b/src/libstd/ptr.rs
@@ -481,7 +481,7 @@ struct Pair {
     fn test_position() {
         use libc::c_char;
 
-        do "hello".to_c_str().with_ref |p| {
+        do "hello".with_c_str |p| {
             unsafe {
                 assert!(2u == position(p, |c| *c == 'l' as c_char));
                 assert!(4u == position(p, |c| *c == 'o' as c_char));
@@ -492,9 +492,9 @@ fn test_position() {
 
     #[test]
     fn test_buf_len() {
-        do "hello".to_c_str().with_ref |p0| {
-            do "there".to_c_str().with_ref |p1| {
-                do "thing".to_c_str().with_ref |p2| {
+        do "hello".with_c_str |p0| {
+            do "there".with_c_str |p1| {
+                do "thing".with_c_str |p2| {
                     let v = ~[p0, p1, p2, null()];
                     do v.as_imm_buf |vp, len| {
                         assert_eq!(unsafe { buf_len(vp) }, 3u);
diff --git a/src/libstd/rt/borrowck.rs b/src/libstd/rt/borrowck.rs
index f620a7347a4..ba4cbc66803 100644
--- a/src/libstd/rt/borrowck.rs
+++ b/src/libstd/rt/borrowck.rs
@@ -52,7 +52,7 @@ unsafe fn fail_borrowed(box: *mut raw::Box<()>, file: *c_char, line: size_t) {
     match try_take_task_borrow_list() {
         None => { // not recording borrows
             let msg = "borrowed";
-            do msg.to_c_str().with_ref |msg_p| {
+            do msg.with_c_str |msg_p| {
                 sys::begin_unwind_(msg_p, file, line);
             }
         }
@@ -68,7 +68,7 @@ unsafe fn fail_borrowed(box: *mut raw::Box<()>, file: *c_char, line: size_t) {
                     sep = " and at ";
                 }
             }
-            do msg.to_c_str().with_ref |msg_p| {
+            do msg.with_c_str |msg_p| {
                 sys::begin_unwind_(msg_p, file, line)
             }
         }
@@ -208,7 +208,7 @@ pub unsafe fn unrecord_borrow(a: *u8, old_ref_count: uint,
             let br = borrow_list.pop();
             if br.box != a || br.file != file || br.line != line {
                 let err = fmt!("wrong borrow found, br=%?", br);
-                do err.to_c_str().with_ref |msg_p| {
+                do err.with_c_str |msg_p| {
                     sys::begin_unwind_(msg_p, file, line)
                 }
             }
diff --git a/src/libstd/rt/logging.rs b/src/libstd/rt/logging.rs
index 117795f6c90..4ee65a2b449 100644
--- a/src/libstd/rt/logging.rs
+++ b/src/libstd/rt/logging.rs
@@ -66,7 +66,7 @@ pub fn init(crate_map: *u8) {
     let log_spec = os::getenv("RUST_LOG");
     match log_spec {
         Some(spec) => {
-            do spec.to_c_str().with_ref |buf| {
+            do spec.with_c_str |buf| {
                 unsafe { rust_update_log_settings(crate_map, buf) }
             }
         }
diff --git a/src/libstd/rt/uv/uvio.rs b/src/libstd/rt/uv/uvio.rs
index 038ebad3540..a26b8a3ad59 100644
--- a/src/libstd/rt/uv/uvio.rs
+++ b/src/libstd/rt/uv/uvio.rs
@@ -654,7 +654,7 @@ fn sendto(&mut self, buf: &[u8], dst: SocketAddr) -> Result<(), IoError> {
 
     fn join_multicast(&mut self, multi: IpAddr) -> Result<(), IoError> {
         let r = unsafe {
-            do multi.to_str().to_c_str().with_ref |m_addr| {
+            do multi.to_str().with_c_str |m_addr| {
                 uvll::udp_set_membership(self.native_handle(), m_addr,
                                          ptr::null(), uvll::UV_JOIN_GROUP)
             }
@@ -668,7 +668,7 @@ fn join_multicast(&mut self, multi: IpAddr) -> Result<(), IoError> {
 
     fn leave_multicast(&mut self, multi: IpAddr) -> Result<(), IoError> {
         let r = unsafe {
-            do multi.to_str().to_c_str().with_ref |m_addr| {
+            do multi.to_str().with_c_str |m_addr| {
                 uvll::udp_set_membership(self.native_handle(), m_addr,
                                          ptr::null(), uvll::UV_LEAVE_GROUP)
             }
diff --git a/src/libstd/rt/uv/uvll.rs b/src/libstd/rt/uv/uvll.rs
index e240395a495..11d64f4697c 100644
--- a/src/libstd/rt/uv/uvll.rs
+++ b/src/libstd/rt/uv/uvll.rs
@@ -373,12 +373,12 @@ pub unsafe fn is_ip6_addr(addr: *sockaddr) -> bool {
 }
 
 pub unsafe fn malloc_ip4_addr(ip: &str, port: int) -> *sockaddr_in {
-    do ip.to_c_str().with_ref |ip_buf| {
+    do ip.with_c_str |ip_buf| {
         rust_uv_ip4_addrp(ip_buf as *u8, port as libc::c_int)
     }
 }
 pub unsafe fn malloc_ip6_addr(ip: &str, port: int) -> *sockaddr_in6 {
-    do ip.to_c_str().with_ref |ip_buf| {
+    do ip.with_c_str |ip_buf| {
         rust_uv_ip6_addrp(ip_buf as *u8, port as libc::c_int)
     }
 }
diff --git a/src/libstd/run.rs b/src/libstd/run.rs
index 31e317604c7..f7c684726cd 100644
--- a/src/libstd/run.rs
+++ b/src/libstd/run.rs
@@ -506,7 +506,7 @@ fn spawn_process_os(prog: &str, args: &[~str],
 
         do with_envp(env) |envp| {
             do with_dirp(dir) |dirp| {
-                do cmd.to_c_str().with_ref |cmdp| {
+                do cmd.with_c_str |cmdp| {
                     let created = CreateProcessA(ptr::null(), cast::transmute(cmdp),
                                                  ptr::mut_null(), ptr::mut_null(), TRUE,
                                                  0, envp, dirp, &mut si, &mut pi);
@@ -775,7 +775,7 @@ fn with_envp<T>(env: Option<&[(~str, ~str)]>, cb: &fn(*mut c_void) -> T) -> T {
 
 fn with_dirp<T>(d: Option<&Path>, cb: &fn(*libc::c_char) -> T) -> T {
     match d {
-      Some(dir) => dir.to_c_str().with_ref(|buf| cb(buf)),
+      Some(dir) => dir.with_c_str(|buf| cb(buf)),
       None => cb(ptr::null())
     }
 }
diff --git a/src/libstd/sys.rs b/src/libstd/sys.rs
index 03e6412fcb8..bfb9bee7802 100644
--- a/src/libstd/sys.rs
+++ b/src/libstd/sys.rs
@@ -105,8 +105,8 @@ pub trait FailWithCause {
 
 impl FailWithCause for ~str {
     fn fail_with(cause: ~str, file: &'static str, line: uint) -> ! {
-        do cause.to_c_str().with_ref |msg_buf| {
-            do file.to_c_str().with_ref |file_buf| {
+        do cause.with_c_str |msg_buf| {
+            do file.with_c_str |file_buf| {
                 begin_unwind_(msg_buf, file_buf, line as libc::size_t)
             }
         }
@@ -115,8 +115,8 @@ fn fail_with(cause: ~str, file: &'static str, line: uint) -> ! {
 
 impl FailWithCause for &'static str {
     fn fail_with(cause: &'static str, file: &'static str, line: uint) -> ! {
-        do cause.to_c_str().with_ref |msg_buf| {
-            do file.to_c_str().with_ref |file_buf| {
+        do cause.with_c_str |msg_buf| {
+            do file.with_c_str |file_buf| {
                 begin_unwind_(msg_buf, file_buf, line as libc::size_t)
             }
         }
diff --git a/src/libstd/unstable/dynamic_lib.rs b/src/libstd/unstable/dynamic_lib.rs
index 49e3e0777df..005cedd0ffd 100644
--- a/src/libstd/unstable/dynamic_lib.rs
+++ b/src/libstd/unstable/dynamic_lib.rs
@@ -66,7 +66,7 @@ pub unsafe fn symbol<T>(&self, symbol: &str) -> Result<T, ~str> {
         // T but that feature is still unimplemented
 
         let maybe_symbol_value = do dl::check_for_errors_in {
-            do symbol.to_c_str().with_ref |raw_string| {
+            do symbol.with_c_str |raw_string| {
                 dl::symbol(self.handle, raw_string)
             }
         };
@@ -145,7 +145,7 @@ mod dl {
     use result::*;
 
     pub unsafe fn open_external(filename: &path::Path) -> *libc::c_void {
-        do filename.to_c_str().with_ref |raw_name| {
+        do filename.with_c_str |raw_name| {
             dlopen(raw_name, Lazy as libc::c_int)
         }
     }
diff --git a/src/libstd/unstable/lang.rs b/src/libstd/unstable/lang.rs
index 956ffb82902..91b4283ba12 100644
--- a/src/libstd/unstable/lang.rs
+++ b/src/libstd/unstable/lang.rs
@@ -29,7 +29,7 @@ pub fn fail_bounds_check(file: *c_char, line: size_t,
                          index: size_t, len: size_t) {
     let msg = fmt!("index out of bounds: the len is %d but the index is %d",
                     len as int, index as int);
-    do msg.to_c_str().with_ref |buf| {
+    do msg.with_c_str |buf| {
         fail_(buf, file, line);
     }
 }
diff --git a/src/test/run-pass/c-stack-returning-int64.rs b/src/test/run-pass/c-stack-returning-int64.rs
index e91c11f5cd0..22c5e9dad25 100644
--- a/src/test/run-pass/c-stack-returning-int64.rs
+++ b/src/test/run-pass/c-stack-returning-int64.rs
@@ -20,11 +20,11 @@ mod libc {
 }
 
 fn atol(s: ~str) -> int {
-    s.to_c_str().with_ref(|x| unsafe { libc::atol(x as *u8) })
+    s.with_c_str(|x| unsafe { libc::atol(x as *u8) })
 }
 
 fn atoll(s: ~str) -> i64 {
-    s.to_c_str().with_ref(|x| unsafe { libc::atoll(x as *u8) })
+    s.with_c_str(|x| unsafe { libc::atoll(x as *u8) })
 }
 
 pub fn main() {
diff --git a/src/test/run-pass/foreign-fn-linkname.rs b/src/test/run-pass/foreign-fn-linkname.rs
index b5a114ef223..827f950dab2 100644
--- a/src/test/run-pass/foreign-fn-linkname.rs
+++ b/src/test/run-pass/foreign-fn-linkname.rs
@@ -26,7 +26,7 @@ mod libc {
 fn strlen(str: ~str) -> uint {
     unsafe {
         // C string is terminated with a zero
-        do str.to_c_str().with_ref |buf| {
+        do str.with_c_str |buf| {
             libc::my_strlen(buf as *u8)
         }
     }
-- 
2.44.0