LibRaw 0.17 (and before) known to be not compilable by gcc6. So if you're using gcc6 and it builds OK, it means you use some modified source.
The patch proposed by community brokes 4-color processing in vng_interpolate. meanwhile, it looks like Debian community use this patch for debian repo: https://github.com/LibRaw/LibRaw/issues/56
(And, yes, they know that the patch is broken, see discussion in github issue thread)
LibRaw 0.17 (and before) known to be not compilable by gcc6. So if you're using gcc6 and it builds OK, it means you use some modified source.
The patch proposed by community brokes 4-color processing in vng_interpolate. meanwhile, it looks like Debian community use this patch for debian repo: https://github.com/LibRaw/LibRaw/issues/56
(And, yes, they know that the patch is broken, see discussion in github issue thread)