There is a fallout from the switch to binutils 2.17: the binaries
created by 2.17 aren't recognized by the in-tree gdb because it's built
with the bfd code from 2.15.
My understanding is that the in-tree gdb can't be made to run with bfd
from 2.17 without significant non-trivial changes, so I'd suggest the
following diff.
Index: gnu/usr.bin/binutils/bfd/elf32-sh.c
===================================================================
RCS file: /OpenBSD/src/gnu/usr.bin/binutils/bfd/elf32-sh.c,v
retrieving revision 1.3
diff -u -p -r1.3 elf32-sh.c
--- gnu/usr.bin/binutils/bfd/elf32-sh.c 22 Dec 2014 14:09:58 -0000 1.3
+++ gnu/usr.bin/binutils/bfd/elf32-sh.c 20 Nov 2015 20:56:20 -0000
@@ -6849,6 +6849,7 @@ sh_elf_set_mach_from_flags (bfd *abfd)
break;
case EF_SH_UNKNOWN:
case EF_SH4:
+ case 23: /* EF_SH2A_SH4 */
bfd_default_set_arch_mach (abfd, bfd_arch_sh, bfd_mach_sh4);
break;
case EF_SH4_NOFPU:
