From 65d11b5c6562c57d61bf0db88736da06b8b77423 Mon Sep 17 00:00:00 2001
From: Erik Desjardins <erikdesjardins@users.noreply.github.com>
Date: Sun, 11 Jun 2023 13:41:46 -0400
Subject: [PATCH] extern-fn-explicit-align test: add wrapped and lower
 requested alignment, improve assertions

---
 .../run-make/extern-fn-explicit-align/test.c  | 48 +++++++++++++++++--
 .../run-make/extern-fn-explicit-align/test.rs | 38 +++++++++++----
 2 files changed, 71 insertions(+), 15 deletions(-)

diff --git a/tests/run-make/extern-fn-explicit-align/test.c b/tests/run-make/extern-fn-explicit-align/test.c
index 154b63ff45b3..292e7a822b59 100644
--- a/tests/run-make/extern-fn-explicit-align/test.c
+++ b/tests/run-make/extern-fn-explicit-align/test.c
@@ -3,6 +3,12 @@
 #include <stdint.h>
 #include <string.h>
 
+struct BoolAndU32
+{
+    bool a;
+    uint32_t b;
+};
+
 #ifdef _MSC_VER
 __declspec(align(16))
 struct TwoU64s
@@ -18,12 +24,28 @@ struct __attribute__((aligned(16))) TwoU64s
 };
 #endif
 
-struct BoolAndU32
+struct WrappedU64s
 {
-    bool a;
-    uint32_t b;
+    struct TwoU64s a;
 };
 
+#ifdef _MSC_VER
+__declspec(align(1))
+struct LowerAlign
+{
+    uint64_t a;
+    uint64_t b;
+};
+#else
+struct __attribute__((aligned(1))) LowerAlign
+{
+    uint64_t a;
+    uint64_t b;
+};
+#endif
+
+
+
 int32_t many_args(
     void *a,
     void *b,
@@ -34,11 +56,27 @@ int32_t many_args(
     void *g,
     struct TwoU64s h,
     void *i,
-    void *j,
+    struct WrappedU64s j,
     void *k,
-    void *l,
+    struct LowerAlign l,
     const char *m)
 {
+    assert(!a);
+    assert(!b);
+    assert(!c);
+    assert(d == 42);
+    assert(e);
+    assert(f.a);
+    assert(f.b == 1337);
+    assert(!g);
+    assert(h.a == 1);
+    assert(h.b == 2);
+    assert(!i);
+    assert(j.a.a == 3);
+    assert(j.a.b == 4);
+    assert(!k);
+    assert(l.a == 5);
+    assert(l.b == 6);
     assert(strcmp(m, "Hello world") == 0);
     return 0;
 }
diff --git a/tests/run-make/extern-fn-explicit-align/test.rs b/tests/run-make/extern-fn-explicit-align/test.rs
index 4621c36c4942..c5b3e24048ee 100644
--- a/tests/run-make/extern-fn-explicit-align/test.rs
+++ b/tests/run-make/extern-fn-explicit-align/test.rs
@@ -3,6 +3,13 @@
 use std::ffi::{CStr, c_char};
 use std::ptr::null_mut;
 
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub struct BoolAndU32 {
+    pub a: bool,
+    pub b: u32,
+}
+
 #[derive(Copy, Clone)]
 #[repr(C)]
 #[repr(align(16))]
@@ -11,11 +18,20 @@ pub struct TwoU64s {
     pub b: u64,
 }
 
-#[repr(C)]
 #[derive(Copy, Clone)]
-pub struct BoolAndU32 {
-    pub a: bool,
-    pub b: u32,
+#[repr(C)]
+pub struct WrappedU64s {
+    pub a: TwoU64s
+}
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+// Even though requesting align 1 can never change the alignment, it still affects the ABI
+// on some platforms like i686-windows.
+#[repr(align(1))]
+pub struct LowerAlign {
+    pub a: u64,
+    pub b: u64,
 }
 
 #[link(name = "test", kind = "static")]
@@ -30,9 +46,9 @@ extern "C" {
         g: *mut (),
         h: TwoU64s,
         i: *mut (),
-        j: *mut (),
+        j: WrappedU64s,
         k: *mut (),
-        l: *mut (),
+        l: LowerAlign,
         m: *const c_char,
     ) -> i32;
 }
@@ -40,23 +56,25 @@ extern "C" {
 const STRING: &CStr = unsafe { CStr::from_bytes_with_nul_unchecked(b"Hello world\0") };
 
 fn main() {
+    let bool_and_u32 = BoolAndU32 { a: true, b: 1337 };
     let two_u64s = TwoU64s { a: 1, b: 2 };
-    let bool_and_u32 = BoolAndU32 { a: true, b: 3 };
+    let wrapped = WrappedU64s { a: TwoU64s { a: 3, b: 4 } };
+    let lower = LowerAlign { a: 5, b: 6 };
     let string = STRING;
     unsafe {
         many_args(
             null_mut(),
             null_mut(),
             null_mut(),
-            4,
+            42,
             true,
             bool_and_u32,
             null_mut(),
             two_u64s,
             null_mut(),
+            wrapped,
             null_mut(),
-            null_mut(),
-            null_mut(),
+            lower,
             string.as_ptr(),
         );
     }