Auto merge of #106458 - albertlarsan68:move-tests, r=jyn514

Move src/test to the root

See MCP at rust-lang/compiler-team#573

There may be more changes needed.

The first commit is just the move of the files:
You can check that the first commit did not do anything else than renames by running
```
git diff --diff-filter=r -M100% <rust-lang remote>/master <first commit hash>
```
The output should be empty, because the filter excludes renames, and the match threshold for qualifying a rename is 100%.

The second one is mostly a "find and replace" of `src/test` to `tests` and whatever is needed to make CI pass.

What is left to do:
---

- [x] Move directory
- [ ] Change references to `src/test`
    - [x] Change references in-tree
    - [ ] Change references in submodules / out-of-tree docs
- [x] Make CI pass:
    - [x] Fix tidy
    - [x] Fix tests
    - [x] Bless tests if needed (shouldn't normally)
- [ ] Merge it !

1 files changed, 95 insertions, 0 deletions

diff --git a/tests/ui/layout/zero-sized-array-union.rs b/tests/ui/layout/zero-sized-array-union.rs
new file mode 100644
index 00000000000..1a662ba4467
--- /dev/null
+++ b/tests/ui/layout/zero-sized-array-union.rs
@@ -0,0 +1,95 @@
+#![feature(rustc_attrs)]
+
+// Various tests around the behavior of zero-sized arrays and
+// unions. This matches the behavior of modern C compilers, though
+// older compilers (and sometimes clang) treat `T[0]` as a "flexible
+// array member". See more
+// details in #56877.
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+struct Empty { }
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+struct Empty2 {
+    e: Empty
+}
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+struct Empty3 {
+    z: [f32; 0],
+}
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+struct Empty4 {
+    e: Empty3
+}
+
+#[repr(C)]
+union U1 {
+    s: Empty
+}
+
+#[repr(C)]
+union U2 {
+    s: Empty2
+}
+
+#[repr(C)]
+union U3 {
+    s: Empty3
+}
+
+#[repr(C)]
+union U4 {
+    s: Empty4
+}
+
+#[repr(C)]
+struct Baz1 {
+    x: f32,
+    y: f32,
+    u: U1,
+}
+
+#[rustc_layout(homogeneous_aggregate)]
+type TestBaz1 = Baz1;
+//~^ ERROR homogeneous_aggregate: Ok(Homogeneous
+
+#[repr(C)]
+struct Baz2 {
+    x: f32,
+    y: f32,
+    u: U2,
+}
+
+#[rustc_layout(homogeneous_aggregate)]
+type TestBaz2 = Baz2;
+//~^ ERROR homogeneous_aggregate: Ok(Homogeneous
+
+#[repr(C)]
+struct Baz3 {
+    x: f32,
+    y: f32,
+    u: U3,
+}
+
+#[rustc_layout(homogeneous_aggregate)]
+type TestBaz3 = Baz3;
+//~^ ERROR homogeneous_aggregate: Ok(Homogeneous
+
+#[repr(C)]
+struct Baz4 {
+    x: f32,
+    y: f32,
+    u: U4,
+}
+
+#[rustc_layout(homogeneous_aggregate)]
+type TestBaz4 = Baz4;
+//~^ ERROR homogeneous_aggregate: Ok(Homogeneous
+
+fn main() { }