Adding placeholder for the deleted binarydir config.

DEBUGMALLOC broke because of this.
Test: unbreak DEBUGMALLOC.

It correctly launch and checks testsuite now.
Test: remove the optimization for restore_object.

It cause false postive to DEBUG_MALLOC.
Make tests/crasher runs without DEBUGMALLOC.
Adding GCMALLOC as a malloc choice.

automatic GC == MAGIC! needs libgc-dev installed