Make backtraces work on Windows GNU targets again.

This is done by adding a function that can return a filename
to pass to backtrace_create_state. The filename is obtained in
a safe way by first getting the filename, locking the file so it can't
be moved, and then getting the filename again and making sure it's the same.

See: https://github.com/rust-lang/rust/pull/37359#issuecomment-260123399
Issue: #33985

1 files changed, 7 insertions, 0 deletions

diff --git a/src/libstd/sys/unix/backtrace/mod.rs b/src/libstd/sys/unix/backtrace/mod.rs
index d7c05e513f6..e3f1b23f7a2 100644
--- a/src/libstd/sys/unix/backtrace/mod.rs
+++ b/src/libstd/sys/unix/backtrace/mod.rs
@@ -83,9 +83,16 @@
 /// to symbols. This is a bit of a hokey implementation as-is, but it works for
 /// all unix platforms we support right now, so it at least gets the job done.
 
+use io;
+use fs;
+
 pub use self::tracing::write;
 
 // tracing impls:
 mod tracing;
 // symbol resolvers:
 mod printing;
+
+pub fn get_executable_filename() -> io::Result<(Vec<i8>, fs::File)> {
+    Err(io::Error::new(io::ErrorKind::Other, "Not implemented"))
+}