bug#15344: 24.3; Crash when yanking in c-mode

[Lars Ljung]

Maybe this is a better way to describe how to reproduce the segfault:

Start with emacs -Q

C-x b * t e s t * <return> M-x c - m o d e <return>
i n t SPC t e s t ( i n t SPC * p ) ; C-SPC M-b M-b
M-b M-w C-e <return> # d e f i n e SPC T E S T ( p
) SPC C-y

I've had a look at the code but unfortunately I don't have enough
knowledge about the Emacs internals to understand what's going on.

Regards,
Lars Ljung