diff --git a/klee-examples/src/main2.rs b/klee-examples/src/main2.rs
index e28b1b48d34d4058288d01375b6e1f9afd6d663e..df1d7d27cac50ab5aa565b9db901ec3242a874a5 100644
--- a/klee-examples/src/main2.rs
+++ b/klee-examples/src/main2.rs
@@ -1,4 +1,40 @@
 //! showcase volatile register
+//! 
+//! $ cargo klee --bin main2 -r -g
+//! ...
+//! Reading symbols from main2.replay...done.
+//! 
+//! (gdb) set env KTEST_FILE=klee-last/test000001.ktest
+//! (gdb) run
+//! Starting program: /home/pln/rust/cargo-klee/klee-examples/target/release/deps/main2.replay
+//! [Inferior 1 (process 25074) exited with code 01]
+//! 
+//! (gdb) set env KTEST_FILE=klee-last/test000003.ktest
+//! (gdb) run
+//! Starting program: /home/pln/rust/cargo-klee/klee-examples/target/release/deps/main2.replay
+//! rust_begin_unwind (_info=0x7fffffffd678)
+//!    at /home/pln/.cargo/git/checkouts/cargo-klee-8f30fda3bd23bb30/68dc73d/src/lang_items.rs:66
+//!            unsafe { intrinsics::abort() }
+//! (gdb) backtrace
+//! #0  rust_begin_unwind (_info=0x7fffffffd678)
+//!    at /home/pln/.cargo/git/checkouts/cargo-klee-8f30fda3bd23bb30/68dc73d/src/lang_items.rs:6
+//! #1  0x000055555555531c in core::panicking::panic_fmt () at src/libcore/panicking.rs:95
+//! #2  0x000055555555539b in core::panicking::panic () at src/libcore/panicking.rs:59
+//! #3  0x00005555555552a6 in main () at src/main2.rs:54
+//! (gdb) q
+//! A debugging session is active.
+//!
+//!        Inferior 1 [process 25893] will be killed.
+//! $ ktest-tool --write-int target/debug/deps/klee-last/test000003.ktest
+//! ktest file : 'target/debug/deps/klee-last/test000003.ktest'
+//! args       : ['/home/pln/rust/cargo-klee/klee-examples/target/debug/deps/main2-2a0fc03ce12ab528.ll']
+//! num objects: 2
+//! object    0: name: b'register'
+//! object    0: size: 4
+//! object    0: data: 0
+//! object    1: name: b'register'
+//! object    1: size: 4
+//! object    1: data: 0
 
 #![no_std]
 #![no_main]