foreach/array indexing bug

Imported from http://bugzilla.roxen.com/bugzilla/show_bug.cgi?id=7426

Reported by Martin Karlgren marty@roxen.com

$ pike -e 'foreach (({})[1..], mixed e) werror ("e: %O\n", e);' e: 0.0 Segmentation fault: 11

Tested with Pike 8.0.36 on Mac OS X (x86_64) and 8.0.25 on Linux (x86_64).