Auto merge of #2627 - RalfJung:ignore-windows, r=RalfJung

update ignore-windows comments

Turns out 2 of these tests can actually be enabled. :)

src/tools/miri/tests/fail/data_race/stack_pop_race.rs

@@ -1,4 +1,3 @@
-//@ignore-target-windows: Concurrency on Windows is not supported yet.
 //@compile-flags: -Zmiri-preemption-rate=0
 use std::thread;
 

src/tools/miri/tests/fail/panic/no_std.rs

@@ -3,7 +3,7 @@
 // windows tls dtors go through libstd right now, thus this test
 // cannot pass. When windows tls dtors go through the special magic
 // windows linker section, we can run this test on windows again.
-//@ignore-target-windows
+//@ignore-target-windows: no-std not supported on Windows
 
 // Plumbing to let us use `writeln!` to host stderr:
 

src/tools/miri/tests/pass/concurrency/sync.rs

@@ -1,4 +1,4 @@
-//@ignore-target-windows: Concurrency on Windows is not supported yet.
+//@ignore-target-windows: Condvars on Windows are not supported yet.
 //@compile-flags: -Zmiri-disable-isolation -Zmiri-strict-provenance
 
 use std::sync::{Arc, Barrier, Condvar, Mutex, Once, RwLock};

src/tools/miri/tests/pass/concurrency/sync_nopreempt.rs

@@ -1,4 +1,4 @@
-//@ignore-target-windows: Concurrency on Windows is not supported yet.
+//@ignore-target-windows: Condvars on Windows are not supported yet.
 // We are making scheduler assumptions here.
 //@compile-flags: -Zmiri-strict-provenance -Zmiri-preemption-rate=0
 

src/tools/miri/tests/pass/no_std.rs

@@ -3,7 +3,7 @@
 // windows tls dtors go through libstd right now, thus this test
 // cannot pass. When windows tls dtors go through the special magic
 // windows linker section, we can run this test on windows again.
-//@ignore-target-windows
+//@ignore-target-windows: no-std not supported on Windows
 
 // Plumbing to let us use `writeln!` to host stdout:
 

src/tools/miri/tests/pass/shims/env/current_exe.rs

@@ -1,4 +1,4 @@
-//@ignore-target-windows
+//@ignore-target-windows: current_exe not supported on Windows
 //@only-on-host: the Linux std implementation opens /proc/self/exe, which doesn't work cross-target
 //@compile-flags: -Zmiri-disable-isolation
 use std::env;

src/tools/miri/tests/pass/shims/sleep_long.rs

@@ -1,4 +1,3 @@
-//@ignore-target-windows: no threads nor sleep on Windows
 //@compile-flags: -Zmiri-ignore-leaks -Zmiri-disable-isolation
 use std::sync::{Arc, Mutex};
 use std::thread;