Add a test

Author: checkraisefold

tests/run-make/issue-44282-questionmark-mangle/main.rs

@@ -0,0 +1,11 @@
+#![crate_type = "cdylib"]
+
+#[no_mangle]
+pub extern "C" fn foo(a: i32, b: i32) -> i32 {
+    1
+}
+
+#[export_name = "?bar@@YAXXZ"]
+pub extern "C" fn bar(a: i32, b: i32) -> i32 {
+    2
+}

tests/run-make/issue-44282-questionmark-mangle/rmake.rs

@@ -0,0 +1,9 @@
+// This test verifies that functions including a leading question mark
+// in their export_name attribute successfully compile.
+// This is only an issue on Windows 32-bit.
+
+use run_make_support::{run, run_fail, rustc};
+
+fn main() {
+    rustc().input("main.rs").target("i686-pc-windows-msvc").run();
+}