Reduce the number of unstable features in tests

1 files changed, 15 insertions, 32 deletions

diff --git a/src/test/ui/allocator/no_std-alloc-error-handler-default.rs b/src/test/ui/allocator/no_std-alloc-error-handler-default.rs
index 601fda87b91..56409e71339 100644
--- a/src/test/ui/allocator/no_std-alloc-error-handler-default.rs
+++ b/src/test/ui/allocator/no_std-alloc-error-handler-default.rs
@@ -7,8 +7,9 @@
 // compile-flags:-C panic=abort
 // aux-build:helper.rs
 
-#![feature(start, rustc_private, new_uninit, panic_info_message, lang_items)]
+#![feature(rustc_private, lang_items)]
 #![no_std]
+#![no_main]
 
 extern crate alloc;
 extern crate libc;
@@ -21,6 +22,7 @@ pub fn __aeabi_unwind_cpp_pr0() {}
 pub fn __aeabi_unwind_cpp_pr1() {}
 
 use alloc::boxed::Box;
+use alloc::string::ToString;
 use core::alloc::{GlobalAlloc, Layout};
 use core::ptr::null_mut;
 
@@ -30,11 +32,7 @@ struct MyAllocator;
 
 unsafe impl GlobalAlloc for MyAllocator {
     unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
-        if layout.size() < 4096 {
-            libc::malloc(layout.size()) as _
-        } else {
-            null_mut()
-        }
+        if layout.size() < 4096 { libc::malloc(layout.size()) as _ } else { null_mut() }
     }
     unsafe fn dealloc(&self, _ptr: *mut u8, _layout: Layout) {}
 }
@@ -45,26 +43,12 @@ static A: MyAllocator = MyAllocator;
 #[panic_handler]
 fn panic(panic_info: &core::panic::PanicInfo) -> ! {
     unsafe {
-        if let Some(s) = panic_info.payload().downcast_ref::<&str>() {
-            const PSTR: &str = "panic occurred: ";
-            const CR: &str = "\n";
-            libc::write(libc::STDERR_FILENO, PSTR as *const _ as _, PSTR.len());
-            libc::write(libc::STDERR_FILENO, s as *const _ as _, s.len());
-            libc::write(libc::STDERR_FILENO, CR as *const _ as _, CR.len());
-        }
-        if let Some(args) = panic_info.message() {
-            let mut s = alloc::string::String::new();
-            alloc::fmt::write(&mut s, *args).unwrap();
-            let s = s.as_str();
-            const PSTR: &str = "panic occurred: ";
-            const CR: &str = "\n";
-            libc::write(libc::STDERR_FILENO, PSTR as *const _ as _, PSTR.len());
-            libc::write(libc::STDERR_FILENO, s as *const _ as _, s.len());
-            libc::write(libc::STDERR_FILENO, CR as *const _ as _, CR.len());
-        } else {
-            const PSTR: &str = "panic occurred\n";
-            libc::write(libc::STDERR_FILENO, PSTR as *const _ as _, PSTR.len());
-        }
+        let s = panic_info.to_string();
+        const PSTR: &str = "panic occurred: ";
+        const CR: &str = "\n";
+        libc::write(libc::STDERR_FILENO, PSTR.as_ptr() as *const _, PSTR.len());
+        libc::write(libc::STDERR_FILENO, s.as_ptr() as *const _, s.len());
+        libc::write(libc::STDERR_FILENO, CR.as_ptr() as *const _, CR.len());
         libc::exit(0)
     }
 }
@@ -74,15 +58,14 @@ fn panic(panic_info: &core::panic::PanicInfo) -> ! {
 // in these libraries will refer to `rust_eh_personality` if LLVM can not *prove* the contents won't
 // unwind. So, for this test case we will define the symbol.
 #[lang = "eh_personality"]
-extern fn rust_eh_personality() {}
+extern "C" fn rust_eh_personality() {}
 
-#[derive(Debug)]
+#[derive(Default, Debug)]
 struct Page(#[allow(unused_tuple_struct_fields)] [[u64; 32]; 16]);
 
-#[start]
-pub fn main(_argc: isize, _argv: *const *const u8) -> isize {
-    let zero = Box::<Page>::new_zeroed();
-    let zero = unsafe { zero.assume_init() };
+#[no_mangle]
+fn main(_argc: i32, _argv: *const *const u8) -> isize {
+    let zero = Box::<Page>::new(Default::default());
     helper::work_with(&zero);
     1
 }