From 7d5ff8b8bd5b1bf4721fd9a3e34b2e90e670be09 Mon Sep 17 00:00:00 2001
From: Chris Denton <chris@chrisdenton.dev>
Date: Mon, 30 Dec 2024 11:25:00 +0000
Subject: [PATCH 1/2] Windows: Enable issue 70093 link tests

---
 src/tools/tidy/src/issues.txt                 |  2 --
 .../issue-70093/issue-70093.rs                | 10 ----------
 ...-link-directives.rs => link-directives.rs} |  1 -
 .../issue-70093/link-native-libraries.rs      | 20 +++++++++++++++++++
 4 files changed, 20 insertions(+), 13 deletions(-)
 delete mode 100644 tests/ui/link-native-libs/issue-70093/issue-70093.rs
 rename tests/ui/link-native-libs/issue-70093/{issue-70093-link-directives.rs => link-directives.rs} (82%)
 create mode 100644 tests/ui/link-native-libs/issue-70093/link-native-libraries.rs

diff --git a/src/tools/tidy/src/issues.txt b/src/tools/tidy/src/issues.txt
index 25cd32063aab8..54de2ef83148f 100644
--- a/src/tools/tidy/src/issues.txt
+++ b/src/tools/tidy/src/issues.txt
@@ -2710,8 +2710,6 @@ ui/limits/issue-75158-64.rs
 ui/link-native-libs/issue-109144.rs
 ui/link-native-libs/issue-43925.rs
 ui/link-native-libs/issue-43926.rs
-ui/link-native-libs/issue-70093/issue-70093-link-directives.rs
-ui/link-native-libs/issue-70093/issue-70093.rs
 ui/linkage-attr/auxiliary/issue-12133-dylib.rs
 ui/linkage-attr/auxiliary/issue-12133-dylib2.rs
 ui/linkage-attr/auxiliary/issue-12133-rlib.rs
diff --git a/tests/ui/link-native-libs/issue-70093/issue-70093.rs b/tests/ui/link-native-libs/issue-70093/issue-70093.rs
deleted file mode 100644
index 8697423933893..0000000000000
--- a/tests/ui/link-native-libs/issue-70093/issue-70093.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-//@ run-pass
-//@ compile-flags: -Zlink-native-libraries=no -Cdefault-linker-libraries=yes
-//@ ignore-windows - this will probably only work on unixish systems
-//@ ignore-fuchsia - missing __libc_start_main for some reason (#84733)
-//@ ignore-cross-compile - default-linker-libraries=yes doesn't play well with cross compiling
-
-#[link(name = "some-random-non-existent-library", kind = "static")]
-extern "C" {}
-
-fn main() {}
diff --git a/tests/ui/link-native-libs/issue-70093/issue-70093-link-directives.rs b/tests/ui/link-native-libs/issue-70093/link-directives.rs
similarity index 82%
rename from tests/ui/link-native-libs/issue-70093/issue-70093-link-directives.rs
rename to tests/ui/link-native-libs/issue-70093/link-directives.rs
index 9c60affbccd59..c67536d39e7f1 100644
--- a/tests/ui/link-native-libs/issue-70093/issue-70093-link-directives.rs
+++ b/tests/ui/link-native-libs/issue-70093/link-directives.rs
@@ -1,6 +1,5 @@
 //@ run-pass
 //@ compile-flags: -Zlink-directives=no
-//@ ignore-windows - this will probably only work on unixish systems
 //@ ignore-fuchsia - missing __libc_start_main for some reason (#84733)
 //@ ignore-cross-compile - default-linker-libraries=yes doesn't play well with cross compiling
 
diff --git a/tests/ui/link-native-libs/issue-70093/link-native-libraries.rs b/tests/ui/link-native-libs/issue-70093/link-native-libraries.rs
new file mode 100644
index 0000000000000..3e14e33ba3940
--- /dev/null
+++ b/tests/ui/link-native-libs/issue-70093/link-native-libraries.rs
@@ -0,0 +1,20 @@
+//@ run-pass
+//@ compile-flags: -Zlink-native-libraries=no -Cdefault-linker-libraries=yes
+//@ ignore-fuchsia - missing __libc_start_main for some reason (#84733)
+//@ ignore-cross-compile - default-linker-libraries=yes doesn't play well with cross compiling
+
+//@ revisions: other
+//@[other] ignore-msvc
+
+//@ revisions: msvc
+// On Windows MSVC, default-linker-libraries=yes doesn't work because
+// rustc drives the linker directly instead of going through another compiler.
+// Therefore rustc would need to implement default-linker-libraries itself but doesn't.
+// So instead we use -Clink-arg to directly set the required msvcrt.lib as a link arg.
+//@[msvc] compile-flags: -Clink-arg=msvcrt.lib
+//@[msvc] only-msvc
+
+#[link(name = "some-random-non-existent-library", kind = "static")]
+extern "C" {}
+
+fn main() {}

From dc1f2be449d5452f2f89855b7476b716bed7f671 Mon Sep 17 00:00:00 2001
From: Chris Denton <chris@chrisdenton.dev>
Date: Tue, 31 Dec 2024 02:25:35 +0000
Subject: [PATCH 2/2] Add comments to -Zlink-* tests

---
 tests/ui/link-native-libs/issue-70093/link-directives.rs    | 5 +++++
 .../link-native-libs/issue-70093/link-native-libraries.rs   | 6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/tests/ui/link-native-libs/issue-70093/link-directives.rs b/tests/ui/link-native-libs/issue-70093/link-directives.rs
index c67536d39e7f1..1dc44c996fcd9 100644
--- a/tests/ui/link-native-libs/issue-70093/link-directives.rs
+++ b/tests/ui/link-native-libs/issue-70093/link-directives.rs
@@ -1,8 +1,13 @@
+// Ensure that `#[link]` attributes are entirely ignore when using `-Zlink-directives=no`.
+
 //@ run-pass
 //@ compile-flags: -Zlink-directives=no
 //@ ignore-fuchsia - missing __libc_start_main for some reason (#84733)
 //@ ignore-cross-compile - default-linker-libraries=yes doesn't play well with cross compiling
 
+// Usually these `#[link]` attribute would cause `libsome-random-non-existent-library`
+// to be passed to the linker, causing it to fail because the file doesn't exist.
+// However, with -Zlink-directives=no, the `#[link]` is ignored.
 #[link(name = "some-random-non-existent-library", kind = "static")]
 extern "C" {}
 
diff --git a/tests/ui/link-native-libs/issue-70093/link-native-libraries.rs b/tests/ui/link-native-libs/issue-70093/link-native-libraries.rs
index 3e14e33ba3940..b4dc9fb5cde17 100644
--- a/tests/ui/link-native-libs/issue-70093/link-native-libraries.rs
+++ b/tests/ui/link-native-libs/issue-70093/link-native-libraries.rs
@@ -1,3 +1,6 @@
+// Ensure that rust does not pass native libraries to the linker when
+// `-Zlink-native-libraries=no` is used.
+
 //@ run-pass
 //@ compile-flags: -Zlink-native-libraries=no -Cdefault-linker-libraries=yes
 //@ ignore-fuchsia - missing __libc_start_main for some reason (#84733)
@@ -14,6 +17,9 @@
 //@[msvc] compile-flags: -Clink-arg=msvcrt.lib
 //@[msvc] only-msvc
 
+// Usually these `#[link]` attribute would cause `libsome-random-non-existent-library`
+// to be passed to the linker, causing it to fail because the file doesn't exist.
+// However, -Zlink-native-libraries=no disables that.
 #[link(name = "some-random-non-existent-library", kind = "static")]
 extern "C" {}