[Bug jit/63969] gccjit segfaults when it can't locate the correct gcc driver program

[dmalcolm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63969

--- Comment #4 from dmalcolm at gcc dot gnu.org ---
Patch posted for review as
https://gcc.gnu.org/ml/gcc-patches/2014-11/msg02617.html