Add a new test for #11 (edition 2018 and no return value)

Author: geofft

examples/neverfree/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "redhook_ex_neverfree"
+version = "0.1.0"
+authors = ["Geoffrey Thomas <[email protected]>"]
+edition = "2018"
+
+[lib]
+name = "neverfree"
+crate_type = ["dylib"]
+
+[dependencies.redhook]
+path = "../.."

examples/neverfree/src/lib.rs

@@ -0,0 +1,4 @@
+redhook::hook! {
+    // Can't have use-after-free vulnerabilities... if you never free anything
+    unsafe fn free(_ptr: *const ()) => my_free { }
+}

test.sh

@@ -18,3 +18,7 @@ cd examples/readlinkspy
 cargo update
 cargo build
 preload libreadlinkspy ls -l /dev/stdin | grep readlink
+
+cd ../neverfree
+cargo update
+cargo build