From da5c911b5f9c0def28662e52e47773d0438f4641 Mon Sep 17 00:00:00 2001
From: Michael Woerister <michaelwoerister@posteo>
Date: Wed, 16 Jun 2021 16:32:42 +0200
Subject: [PATCH] Add regression test  for #85955.

---
 .../auxiliary/same-file-in-two-crates-aux.rs  |  4 ++++
 .../include-macros/same-file-in-two-crates.rs | 21 +++++++++++++++++++
 2 files changed, 25 insertions(+)
 create mode 100644 src/test/ui/include-macros/auxiliary/same-file-in-two-crates-aux.rs
 create mode 100644 src/test/ui/include-macros/same-file-in-two-crates.rs

diff --git a/src/test/ui/include-macros/auxiliary/same-file-in-two-crates-aux.rs b/src/test/ui/include-macros/auxiliary/same-file-in-two-crates-aux.rs
new file mode 100644
index 00000000000..7b680bce49e
--- /dev/null
+++ b/src/test/ui/include-macros/auxiliary/same-file-in-two-crates-aux.rs
@@ -0,0 +1,4 @@
+#[inline]
+pub fn some_function() -> u32 {
+    1
+}
diff --git a/src/test/ui/include-macros/same-file-in-two-crates.rs b/src/test/ui/include-macros/same-file-in-two-crates.rs
new file mode 100644
index 00000000000..f49efa2cf8a
--- /dev/null
+++ b/src/test/ui/include-macros/same-file-in-two-crates.rs
@@ -0,0 +1,21 @@
+// This test makes sure that the compiler can handle the same source file to be
+// part of the local crate *and* an upstream crate. This can happen, for example,
+// when there is some auto-generated code that is part of both a library and an
+// accompanying integration test.
+//
+// The test uses include!() to include a source file that is also part of
+// an upstream crate.
+//
+// This is a regression test for https://github.com/rust-lang/rust/issues/85955.
+
+// check-pass
+// compile-flags: --crate-type=rlib
+// aux-build:same-file-in-two-crates-aux.rs
+extern crate same_file_in_two_crates_aux;
+
+pub fn foo() -> u32 {
+    same_file_in_two_crates_aux::some_function() +
+    some_function()
+}
+
+include!("./auxiliary/same-file-in-two-crates-aux.rs");