7 files changed, 22 insertions, 12 deletions
diff --git a/library/test/src/console.rs b/library/test/src/console.rs
index 024ef48fc51..8f29f1dada5 100644
--- a/library/test/src/console.rs
+++ b/library/test/src/console.rs
@@ -314,9 +314,10 @@ pub fn run_tests_console(opts: &TestOpts, tests: Vec<TestDescAndFn>) -> io::Resu
     let mut st = ConsoleTestState::new(opts)?;
 
     // Prevent the usage of `Instant` in some cases:
-    // - It's currently not supported for wasm targets.
+    // - It's currently not supported for wasm targets without Emscripten nor WASI.
+    // - It's currently not supported for zkvm targets.
     let is_instant_unsupported =
-        (cfg!(target_family = "wasm") && !cfg!(target_os = "wasi")) || cfg!(target_os = "zkvm");
+        (cfg!(target_family = "wasm") && cfg!(target_os = "unknown")) || cfg!(target_os = "zkvm");
 
     let start_time = (!is_instant_unsupported).then(Instant::now);
     run_tests(opts, tests, |x| on_test_event(&x, &mut st, &mut *out))?;
diff --git a/library/test/src/formatters/junit.rs b/library/test/src/formatters/junit.rs
index 57b1b0fecee..36158b0258a 100644
--- a/library/test/src/formatters/junit.rs
+++ b/library/test/src/formatters/junit.rs
@@ -39,15 +39,15 @@ fn str_to_cdata(s: &str) -> String {
 
 impl<T: Write> OutputFormatter for JunitFormatter<T> {
     fn write_discovery_start(&mut self) -> io::Result<()> {
-        Err(io::Error::new(io::ErrorKind::NotFound, "Not yet implemented!"))
+        Err(io::const_error!(io::ErrorKind::NotFound, "Not yet implemented!"))
     }
 
     fn write_test_discovered(&mut self, _desc: &TestDesc, _test_type: &str) -> io::Result<()> {
-        Err(io::Error::new(io::ErrorKind::NotFound, "Not yet implemented!"))
+        Err(io::const_error!(io::ErrorKind::NotFound, "Not yet implemented!"))
     }
 
     fn write_discovery_finish(&mut self, _state: &ConsoleTestDiscoveryState) -> io::Result<()> {
-        Err(io::Error::new(io::ErrorKind::NotFound, "Not yet implemented!"))
+        Err(io::const_error!(io::ErrorKind::NotFound, "Not yet implemented!"))
     }
 
     fn write_run_start(
diff --git a/library/test/src/lib.rs b/library/test/src/lib.rs
index 54f7e4ae79f..7ada3f269a0 100644
--- a/library/test/src/lib.rs
+++ b/library/test/src/lib.rs
@@ -20,6 +20,7 @@
 #![feature(rustdoc_internals)]
 #![feature(file_buffered)]
 #![feature(internal_output_capture)]
+#![feature(io_const_error)]
 #![feature(staged_api)]
 #![feature(process_exitcode_internals)]
 #![feature(panic_can_unwind)]
@@ -184,12 +185,16 @@ pub fn test_main_static_abort(tests: &[&TestDescAndFn]) {
     // If we're being run in SpawnedSecondary mode, run the test here. run_test
     // will then exit the process.
     if let Ok(name) = env::var(SECONDARY_TEST_INVOKER_VAR) {
-        env::remove_var(SECONDARY_TEST_INVOKER_VAR);
+        unsafe {
+            env::remove_var(SECONDARY_TEST_INVOKER_VAR);
+        }
 
         // Convert benchmarks to tests if we're not benchmarking.
         let mut tests = tests.iter().map(make_owned_test).collect::<Vec<_>>();
         if env::var(SECONDARY_TEST_BENCH_BENCHMARKS_VAR).is_ok() {
-            env::remove_var(SECONDARY_TEST_BENCH_BENCHMARKS_VAR);
+            unsafe {
+                env::remove_var(SECONDARY_TEST_BENCH_BENCHMARKS_VAR);
+            }
         } else {
             tests = convert_benchmarks_to_tests(tests);
         };
diff --git a/library/test/src/term/terminfo/mod.rs b/library/test/src/term/terminfo/mod.rs
index 974b8afd598..75fa594908d 100644
--- a/library/test/src/term/terminfo/mod.rs
+++ b/library/test/src/term/terminfo/mod.rs
@@ -90,7 +90,7 @@ impl TermInfo {
 
         get_dbpath_for_term(name)
             .ok_or_else(|| {
-                Error::IoError(io::Error::new(io::ErrorKind::NotFound, "terminfo file not found"))
+                Error::IoError(io::const_error!(io::ErrorKind::NotFound, "terminfo file not found"))
             })
             .and_then(|p| TermInfo::from_path(&(*p)))
     }
diff --git a/library/test/src/term/terminfo/parser/compiled.rs b/library/test/src/term/terminfo/parser/compiled.rs
index e687b3be41f..d1dd0f10d86 100644
--- a/library/test/src/term/terminfo/parser/compiled.rs
+++ b/library/test/src/term/terminfo/parser/compiled.rs
@@ -173,7 +173,7 @@ fn read_le_u32(r: &mut dyn io::Read) -> io::Result<u32> {
 fn read_byte(r: &mut dyn io::Read) -> io::Result<u8> {
     match r.bytes().next() {
         Some(s) => s,
-        None => Err(io::Error::new(io::ErrorKind::Other, "end of file")),
+        None => Err(io::const_error!(io::ErrorKind::Other, "end of file")),
     }
 }
 
diff --git a/library/test/src/term/terminfo/searcher/tests.rs b/library/test/src/term/terminfo/searcher/tests.rs
index e1edd3b25cf..ff532a97d5e 100644
--- a/library/test/src/term/terminfo/searcher/tests.rs
+++ b/library/test/src/term/terminfo/searcher/tests.rs
@@ -11,7 +11,11 @@ fn test_get_dbpath_for_term() {
     }
     assert_eq!(x("screen"), PathBuf::from("/usr/share/terminfo/s/screen"));
     assert_eq!(get_dbpath_for_term(""), None);
-    env::set_var("TERMINFO_DIRS", ":");
+    unsafe {
+        env::set_var("TERMINFO_DIRS", ":");
+    }
     assert_eq!(x("screen"), PathBuf::from("/usr/share/terminfo/s/screen"));
-    env::remove_var("TERMINFO_DIRS");
+    unsafe {
+        env::remove_var("TERMINFO_DIRS");
+    }
 }
diff --git a/library/test/src/term/win.rs b/library/test/src/term/win.rs
index c77e6aac478..62e5c43ea27 100644
--- a/library/test/src/term/win.rs
+++ b/library/test/src/term/win.rs
@@ -52,7 +52,7 @@ struct CONSOLE_SCREEN_BUFFER_INFO {
 
 #[allow(non_snake_case)]
 #[link(name = "kernel32")]
-extern "system" {
+unsafe extern "system" {
     fn SetConsoleTextAttribute(handle: HANDLE, attr: WORD) -> BOOL;
     fn GetStdHandle(which: DWORD) -> HANDLE;
     fn GetConsoleScreenBufferInfo(handle: HANDLE, info: *mut CONSOLE_SCREEN_BUFFER_INFO) -> BOOL;