diff --git a/.travis.yml b/.travis.yml
index 9aa632da05e..d05661a4848 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -30,9 +30,19 @@ script:
   RUST_BACKTRACE=1 cargo test --release --all-features --all &&
   cargo install --all-features --force
 - |
-  # Test cargo miri
+  # Test `cargo miri`
   cd cargo-miri-test &&
-  cargo miri &&
+  if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then
+    MIRI_SYSROOT=~/.xargo/HOST cargo miri -q -- -Zmiri-start-fn
+  else
+    MIRI_SYSROOT=~/.xargo/HOST cargo miri -q -- -Zmiri-start-fn >stdout.real 2>stderr.real &&
+    cat stdout.real stderr.real &&
+    # Test `cargo miri` output. Not on mac because output redirecting doesn't
+    # work. There is no error. It just stops CI.
+    diff -u stdout.ref stdout.real &&
+    diff -u stderr.ref stderr.real
+  fi &&
+  # Test `cargo miri test`
   #cargo miri test &&
   cd ..
 - |
diff --git a/cargo-miri-test/.gitignore b/cargo-miri-test/.gitignore
new file mode 100644
index 00000000000..56f307a7fb1
--- /dev/null
+++ b/cargo-miri-test/.gitignore
@@ -0,0 +1 @@
+*.real
diff --git a/cargo-miri-test/src/main.rs b/cargo-miri-test/src/main.rs
index 07b0e4cee4e..3fb265f6a7b 100644
--- a/cargo-miri-test/src/main.rs
+++ b/cargo-miri-test/src/main.rs
@@ -6,4 +6,6 @@ fn main() {
     let buf = &[1,2,3,4];
     let n = <BigEndian as ByteOrder>::read_u32(buf);
     assert_eq!(n, 0x01020304);
+    //println!("{:#x}", n); FIXME enable once memrchr works in miri
+    eprintln!("standard error");
 }
diff --git a/cargo-miri-test/stderr.ref b/cargo-miri-test/stderr.ref
new file mode 100644
index 00000000000..aa7d1a2bdec
--- /dev/null
+++ b/cargo-miri-test/stderr.ref
@@ -0,0 +1 @@
+standard error
diff --git a/cargo-miri-test/stdout.ref b/cargo-miri-test/stdout.ref
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/src/fn_call.rs b/src/fn_call.rs
index 31b3b4b18d1..9dfff9f5539 100644
--- a/src/fn_call.rs
+++ b/src/fn_call.rs
@@ -612,7 +612,7 @@ fn call_foreign_item(
 
             // Stub out all the other pthread calls to just return 0
             link_name if link_name.starts_with("pthread_") => {
-                info!("ignoring C ABI call: {}", link_name);
+                debug!("ignoring C ABI call: {}", link_name);
                 self.write_null(dest, dest_ty)?;
             }
 
@@ -759,7 +759,8 @@ fn call_missing_fn(
         match &path[..] {
             // A Rust function is missing, which means we are running with MIR missing for libstd (or other dependencies).
             // Still, we can make many things mostly work by "emulating" or ignoring some functions.
-            "std::io::_print" => {
+            "std::io::_print" |
+            "std::io::_eprint" => {
                 warn!(
                     "Ignoring output.  To run programs that print, make sure you have a libstd with full MIR."
                 );
diff --git a/tests/compiletest.rs b/tests/compiletest.rs
index 38d80696728..82a2144a337 100644
--- a/tests/compiletest.rs
+++ b/tests/compiletest.rs
@@ -8,7 +8,6 @@
 use std::slice::SliceConcatExt;
 use std::path::{PathBuf, Path};
 use std::io::Write;
-use std::env;
 
 macro_rules! eprintln {
     ($($arg:tt)*) => {
@@ -111,9 +110,6 @@ fn miri_pass(sysroot: &Path, path: &str, target: &str, host: &str, need_fullmir:
         // For now, only validate without optimizations.  Inlining breaks validation.
         flags.push("-Zmir-emit-validate=1".to_owned());
     }
-    // Control miri logging. This is okay despite concurrent test execution as all tests
-    // will set this env var to the same value.
-    env::set_var("MIRI_LOG", "warn");
     config.target_rustcflags = Some(flags.join(" "));
     compiletest::run_tests(&config);
 }