incr.comp.: Add test case for cache artifact file headers.

1 files changed, 29 insertions, 0 deletions

diff --git a/src/test/incremental/cache_file_headers.rs b/src/test/incremental/cache_file_headers.rs
new file mode 100644
index 00000000000..274a3920be8
--- /dev/null
+++ b/src/test/incremental/cache_file_headers.rs
@@ -0,0 +1,29 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// This test case makes sure that the compiler does not try to re-use anything
+// from the incremental compilation cache if the cache was produced by a
+// different compiler version. This is tested by artificially forcing the
+// emission of a different compiler version in the header of rpass1 artifacts,
+// and then making sure that the only object file of the test program gets
+// re-translated although the program stays unchanged.
+
+// The `l33t haxx0r` Rust compiler is known to produce incr. comp. artifacts
+// that are outrageously incompatible with just about anything, even itself:
+//[rpass1] rustc-env:RUSTC_FORCE_INCR_COMP_ARTIFACT_HEADER="l33t haxx0r rustc 2.1 LTS"
+
+// revisions:rpass1 rpass2
+
+#![feature(rustc_attrs)]
+#![rustc_partition_translated(module="cache_file_headers", cfg="rpass2")]
+
+fn main() {
+    // empty
+}