diff --git a/src/doc/unstable-book/src/language-features/lang-items.md b/src/doc/unstable-book/src/language-features/lang-items.md
index 375b8bd6b82..a2368ee5f4a 100644
--- a/src/doc/unstable-book/src/language-features/lang-items.md
+++ b/src/doc/unstable-book/src/language-features/lang-items.md
@@ -143,7 +143,8 @@ pub extern fn rust_eh_unwind_resume() {
 #[no_mangle]
 pub extern fn rust_begin_panic(_msg: core::fmt::Arguments,
                                _file: &'static str,
-                               _line: u32) -> ! {
+                               _line: u32,
+                               _column: u32) -> ! {
     unsafe { intrinsics::abort() }
 }
 ```
@@ -187,7 +188,8 @@ pub extern fn rust_eh_unwind_resume() {
 #[no_mangle]
 pub extern fn rust_begin_panic(_msg: core::fmt::Arguments,
                                _file: &'static str,
-                               _line: u32) -> ! {
+                               _line: u32,
+                               _column: u32) -> ! {
     unsafe { intrinsics::abort() }
 }
 ```
diff --git a/src/libcore/lib.rs b/src/libcore/lib.rs
index 46467cd3c3e..97aaaffe8bc 100644
--- a/src/libcore/lib.rs
+++ b/src/libcore/lib.rs
@@ -36,8 +36,8 @@
 //!   These functions are often provided by the system libc, but can also be
 //!   provided by the [rlibc crate](https://crates.io/crates/rlibc).
 //!
-//! * `rust_begin_panic` - This function takes three arguments, a
-//!   `fmt::Arguments`, a `&'static str`, and a `u32`. These three arguments
+//! * `rust_begin_panic` - This function takes four arguments, a
+//!   `fmt::Arguments`, a `&'static str`, and two `u32`'s. These four arguments
 //!   dictate the panic message, the file at which panic was invoked, and the
 //!   line and column inside the file. It is up to consumers of this core
 //!   library to define this panic function; it is only required to never