gdb / dwarf issue

[Gary Aitken]

I'm having trouble getting gdb to agree to look at symbols:

$ cd /usr/ports/graphics/rawtherapee
$ make showconfig
===> The following configuration options are available for rawtherapee-4.2_3:
     OPENMP=on: Enable multicore processing using OpenMP
     OPTIMIZED_CFLAGS=off: Use extra compiler optimizations (requires SSE support)

$ file /usr/local/bin/rawtherapee
/usr/local/bin/rawtherapee: ELF 64-bit LSB executable, x86-64, version 1 (FreeBSD), dynamically linked, interpreter /libexec/ld-elf.so.1, for FreeBSD 10.3, not stripped

$ gdb /usr/local/bin/rawtherapee
GNU gdb 6.1.1 [FreeBSD]
<snip>
This GDB was configured as "amd64-marcel-freebsd"...Dwarf Error: wrong version in compilation unit header (is 4, should be 2) [in module /usr/local/bin/rawtherapee]
(gdb) break main
No symbol table is loaded.  Use the "file" command.

My search found implications that a single dependent library with 
optimization turned on could cause this to happen; is that what I'm
seeing here, or something else?

If so, is there an easy way to find out which libraries have compiler 
optimization turned on that causes this?

Or do I need to be running something else like the gdb66 port?

Or?...

Thanks,

Gary