diff --git a/src/test/run-pass/capturing-logging.rs b/src/test/run-pass/capturing-logging.rs
index 171424d8b3b..17cd8db9d39 100644
--- a/src/test/run-pass/capturing-logging.rs
+++ b/src/test/run-pass/capturing-logging.rs
@@ -43,5 +43,5 @@ fn main() {
         debug!("debug");
         info!("info");
     });
-    assert_eq!(r.read_to_str(), ~"info\n");
+    assert_eq!(r.read_to_str().unwrap(), ~"info\n");
 }
diff --git a/src/test/run-pass/core-run-destroy.rs b/src/test/run-pass/core-run-destroy.rs
index 3442e971f4f..f3ddc002333 100644
--- a/src/test/run-pass/core-run-destroy.rs
+++ b/src/test/run-pass/core-run-destroy.rs
@@ -27,8 +27,7 @@ fn test_destroy_once() {
     #[cfg(target_os="android")]
     static PROG: &'static str = "ls"; // android don't have echo binary
 
-    let mut p = run::Process::new(PROG, [], run::ProcessOptions::new())
-        .expect(format!("failed to exec `{}`", PROG));
+    let mut p = run::Process::new(PROG, [], run::ProcessOptions::new()).unwrap();
     p.destroy(); // this shouldn't crash (and nor should the destructor)
 }
 
@@ -39,12 +38,12 @@ fn test_destroy_twice() {
     #[cfg(target_os="android")]
     static PROG: &'static str = "ls"; // android don't have echo binary
 
-    let mut p = run::Process::new(PROG, [], run::ProcessOptions::new())
-        .expect(format!("failed to exec `{}`", PROG));
+    let mut p = match run::Process::new(PROG, [], run::ProcessOptions::new()) {
+        Ok(p) => p,
+        Err(e) => fail!("wut: {}", e),
+    };
     p.destroy(); // this shouldnt crash...
-    io::io_error::cond.trap(|_| {}).inside(|| {
-        p.destroy(); // ...and nor should this (and nor should the destructor)
-    })
+    p.destroy(); // ...and nor should this (and nor should the destructor)
 }
 
 fn test_destroy_actually_kills(force: bool) {
@@ -61,14 +60,14 @@ fn test_destroy_actually_kills(force: bool) {
     #[cfg(unix,not(target_os="android"))]
     fn process_exists(pid: libc::pid_t) -> bool {
         let run::ProcessOutput {output, ..} = run::process_output("ps", [~"-p", pid.to_str()])
-            .expect("failed to exec `ps`");
+            .unwrap();
         str::from_utf8_owned(output).unwrap().contains(pid.to_str())
     }
 
     #[cfg(unix,target_os="android")]
     fn process_exists(pid: libc::pid_t) -> bool {
         let run::ProcessOutput {output, ..} = run::process_output("/system/bin/ps", [pid.to_str()])
-            .expect("failed to exec `/system/bin/ps`");
+            .unwrap();
         str::from_utf8_owned(output).unwrap().contains(~"root")
     }
 
@@ -93,7 +92,7 @@ fn test_destroy_actually_kills(force: bool) {
 
     // this process will stay alive indefinitely trying to read from stdin
     let mut p = run::Process::new(BLOCK_COMMAND, [], run::ProcessOptions::new())
-        .expect(format!("failed to exec `{}`", BLOCK_COMMAND));
+        .unwrap();
 
     assert!(process_exists(p.get_id()));
 
diff --git a/src/test/run-pass/ifmt.rs b/src/test/run-pass/ifmt.rs
index cc59ce5d8b2..b66446b0cfe 100644
--- a/src/test/run-pass/ifmt.rs
+++ b/src/test/run-pass/ifmt.rs
@@ -12,6 +12,7 @@
 
 #[feature(macro_rules)];
 #[deny(warnings)];
+#[allow(unused_must_use)];
 
 use std::fmt;
 use std::io::MemWriter;
@@ -22,10 +23,14 @@ struct A;
 struct B;
 
 impl fmt::Signed for A {
-    fn fmt(_: &A, f: &mut fmt::Formatter) { f.buf.write("aloha".as_bytes()); }
+    fn fmt(_: &A, f: &mut fmt::Formatter) -> fmt::Result {
+        f.buf.write("aloha".as_bytes())
+    }
 }
 impl fmt::Signed for B {
-    fn fmt(_: &B, f: &mut fmt::Formatter) { f.buf.write("adios".as_bytes()); }
+    fn fmt(_: &B, f: &mut fmt::Formatter) -> fmt::Result {
+        f.buf.write("adios".as_bytes())
+    }
 }
 
 macro_rules! t(($a:expr, $b:expr) => { assert_eq!($a, $b.to_owned()) })
@@ -286,9 +291,9 @@ fn test_format_args() {
     let mut buf = MemWriter::new();
     {
         let w = &mut buf as &mut io::Writer;
-        format_args!(|args| { fmt::write(w, args) }, "{}", 1);
-        format_args!(|args| { fmt::write(w, args) }, "test");
-        format_args!(|args| { fmt::write(w, args) }, "{test}", test=3);
+        format_args!(|args| { fmt::write(w, args); }, "{}", 1);
+        format_args!(|args| { fmt::write(w, args); }, "test");
+        format_args!(|args| { fmt::write(w, args); }, "{test}", test=3);
     }
     let s = str::from_utf8_owned(buf.unwrap()).unwrap();
     t!(s, "1test3");
diff --git a/src/test/run-pass/issue-8398.rs b/src/test/run-pass/issue-8398.rs
index f9169618c2a..0884db63326 100644
--- a/src/test/run-pass/issue-8398.rs
+++ b/src/test/run-pass/issue-8398.rs
@@ -11,7 +11,7 @@
 use std::io;
 
 fn foo(a: &mut io::Writer) {
-    a.write([])
+    a.write([]).unwrap();
 }
 
 pub fn main(){}
diff --git a/src/test/run-pass/logging-only-prints-once.rs b/src/test/run-pass/logging-only-prints-once.rs
index 4aef239f796..dccdc8ae3ba 100644
--- a/src/test/run-pass/logging-only-prints-once.rs
+++ b/src/test/run-pass/logging-only-prints-once.rs
@@ -17,10 +17,11 @@ use std::fmt;
 struct Foo(Cell<int>);
 
 impl fmt::Show for Foo {
-    fn fmt(f: &Foo, _fmt: &mut fmt::Formatter) {
+    fn fmt(f: &Foo, _fmt: &mut fmt::Formatter) -> fmt::Result {
         let Foo(ref f) = *f;
         assert!(f.get() == 0);
         f.set(1);
+        Ok(())
     }
 }
 
diff --git a/src/test/run-pass/signal-exit-status.rs b/src/test/run-pass/signal-exit-status.rs
index dc74e9fb470..0e8ca4d9942 100644
--- a/src/test/run-pass/signal-exit-status.rs
+++ b/src/test/run-pass/signal-exit-status.rs
@@ -19,8 +19,7 @@ pub fn main() {
         // Raise a segfault.
         unsafe { *(0 as *mut int) = 0; }
     } else {
-        let status = run::process_status(args[0], [~"signal"])
-            .expect("failed to exec `signal`");
+        let status = run::process_status(args[0], [~"signal"]).unwrap();
         // Windows does not have signal, so we get exit status 0xC0000028 (STATUS_BAD_STACK).
         match status {
             process::ExitSignal(_) if cfg!(unix) => {},
diff --git a/src/test/run-pass/stat.rs b/src/test/run-pass/stat.rs
index b186a682810..7f04da0734d 100644
--- a/src/test/run-pass/stat.rs
+++ b/src/test/run-pass/stat.rs
@@ -21,8 +21,8 @@ pub fn main() {
 
     {
         match File::create(&path) {
-            None => unreachable!(),
-            Some(f) => {
+            Err(..) => unreachable!(),
+            Ok(f) => {
                 let mut f = f;
                 for _ in range(0u, 1000) {
                     f.write([0]);
@@ -32,5 +32,5 @@ pub fn main() {
     }
 
     assert!(path.exists());
-    assert_eq!(path.stat().size, 1000);
+    assert_eq!(path.stat().unwrap().size, 1000);
 }