opreport --callgraph, problem with libbfd

While doing opreport --callgraph, I get this error (and no callgraph output) :

warning: [vdso] (tgid:13725 range:0xb8032000-0xb8033000) could not be found.
warning: [vdso] (tgid:15520 range:0xb807d000-0xb807e000) could not be found.
CPU: CPU with timer interrupt, speed 0 MHz (estimated)
Profiling through timer interrupt
BFD: BFD (GNU Binutils) 2.19 internal error, aborting at /var/tmp/portage/sys-devel/binutils-2.19/work/binutils-2.19/bfd/pdp11.c line 528 in aout_16_some_aout_object_p

BFD: Please report this bug.

This is with binutils 2.19 on my Gentoo box. I was using an earlier version of binutils and got a similar error, so I emerged the latest binutils to fix it (and, yes, I reemerged oprofile afterwards). The callgraph output worked a couple of times after that, but now I'm consistently getting this libbfd error. This may be hard to reproduce. I'll try to check back on this bug, but in case I miss your response, if you need anymore information from me, please feel free to contact me at ultip[-AT-]ymail.com.