#7 MELT 1.0.1 crashes with -fplugin-arg-melt-mode=findgimple

[Basile STARYNKEVITCH]

the MELT 1.0.1 plugin crashes when invoked with findgimple mode, e.g.

gcc -fplugin=melt -fplugin-arg-melt-mode=findgimple \
    -fplugin-arg-melt-gimple-pattern='?(gimple_assign_plus ?_ ?_ ?_)' \
    -O -c helloworld.c

with the attached helloworld.c

This bug has been found by Boris de Finance and some other students from Univ. Pierre et Marie Curie, Paris, France. See https://groups.google.com/d/msg/gcc-melt/JoTvDNxs2EY/pR7Ado-4NQIJ

A corrective patch will follow.

[Basile STARYNKEVITCH]

The attached patch against melt-1.0.1-plugin-for-gcc-4.7-or-4.8 fixes the bug.