Make not_alloc use max address

Author: Speykious

src/lib.rs

@@ -21,7 +21,7 @@ pub use segfault::segfault;
 pub use transmute::transmute;
 pub use use_after_free::use_after_free;
 
-pub use references::{null, null_mut};
+pub use references::{not_alloc, null, null_mut};
 
 /// Construct a [`String`] from a pointer, capacity and length, in a completely safe manner.
 ///

src/references.rs

@@ -11,7 +11,9 @@ pub fn null_mut<'a, T: 'static>() -> &'a mut T {
 }
 
 /// Not allocate an object. The returned reference is always invalid.
-/// This is equivalent to [`crate::null_mut()`].
+///
+/// **Note:** It turns out that `null` is a valid memory address in WASM.
+/// So here we use the maximum address instead.
 pub fn not_alloc<'a, T: 'static>() -> &'a mut T {
-	null_mut()
+	crate::transmute(usize::MAX)
 }

src/segfault.rs

@@ -12,7 +12,7 @@ pub fn segfault() -> ! {
 
 	// If null doesn't work, try max. Surely that'll stop it.
 	// Confirmed to be effective on WASM.
-	let max = crate::transmute::<usize, &'static mut u8>(usize::MAX);
+	let max = crate::not_alloc::<u8>();
 	*max = 69;
 
 	unreachable!("Sorry, your platform is too strong.")