2 files changed, 7 insertions, 18 deletions
diff --git a/compiler/rustc_driver/Cargo.toml b/compiler/rustc_driver/Cargo.toml
index 0adc006b624..b88b556d143 100644
--- a/compiler/rustc_driver/Cargo.toml
+++ b/compiler/rustc_driver/Cargo.toml
@@ -9,6 +9,7 @@ crate-type = ["dylib"]
 
 [dependencies]
 libc = "0.2"
+atty = "0.2"
 tracing = { version = "0.1.18" }
 tracing-subscriber = { version = "0.2.13", default-features = false, features = ["fmt", "env-filter", "smallvec", "parking_lot", "ansi"] }
 tracing-tree = "0.1.6"
diff --git a/compiler/rustc_driver/src/lib.rs b/compiler/rustc_driver/src/lib.rs
index b3466f49b9f..509f81e1653 100644
--- a/compiler/rustc_driver/src/lib.rs
+++ b/compiler/rustc_driver/src/lib.rs
@@ -546,24 +546,12 @@ impl Compilation {
 #[derive(Copy, Clone)]
 pub struct RustcDefaultCalls;
 
-// FIXME remove these and use winapi 0.3 instead
-// Duplicates: bootstrap/compile.rs, librustc_errors/emitter.rs
-#[cfg(unix)]
 fn stdout_isatty() -> bool {
-    unsafe { libc::isatty(libc::STDOUT_FILENO) != 0 }
+    atty::is(atty::Stream::Stdout)
 }
 
-#[cfg(windows)]
-fn stdout_isatty() -> bool {
-    use winapi::um::consoleapi::GetConsoleMode;
-    use winapi::um::processenv::GetStdHandle;
-    use winapi::um::winbase::STD_OUTPUT_HANDLE;
-
-    unsafe {
-        let handle = GetStdHandle(STD_OUTPUT_HANDLE);
-        let mut out = 0;
-        GetConsoleMode(handle, &mut out) != 0
-    }
+fn stderr_isatty() -> bool {
+    atty::is(atty::Stream::Stderr)
 }
 
 fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
@@ -603,7 +591,7 @@ fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
     }
 }
 
-fn show_content_with_pager(content: &String) {
+fn show_content_with_pager(content: &str) {
     let pager_name = env::var_os("PAGER").unwrap_or_else(|| {
         if cfg!(windows) { OsString::from("more.com") } else { OsString::from("less") }
     });
@@ -1290,7 +1278,7 @@ pub fn init_env_logger(env: &str) {
         Ok(value) => match value.as_ref() {
             "always" => true,
             "never" => false,
-            "auto" => stdout_isatty(),
+            "auto" => stderr_isatty(),
             _ => early_error(
                 ErrorOutputType::default(),
                 &format!(
@@ -1299,7 +1287,7 @@ pub fn init_env_logger(env: &str) {
                 ),
             ),
         },
-        Err(std::env::VarError::NotPresent) => stdout_isatty(),
+        Err(std::env::VarError::NotPresent) => stderr_isatty(),
         Err(std::env::VarError::NotUnicode(_value)) => early_error(
             ErrorOutputType::default(),
             "non-Unicode log color value: expected one of always, never, or auto",