When Olaf Kirch's traceroute is compiled on x86_64 with -O2 probe_recverr() goes into an infinite loop due to padding returned in the control buffer.

Patch:
 - Fix infinite loop in probe_recverr() due to padding on control buffer on x86_64
 - Fix printf() formats on x86_64 in -D output

Diff'ed against SuSE 9.3 version, but should work fine on the base 1.0 version (ftp://ftp.lst.de/pub/people/okir/traceroute)