Meanwhile, I could not confirm the problem.

Here is the changes made for openbayer_sample.cpp:
--- a/samples/openbayer_sample.cpp
+++ b/samples/openbayer_sample.cpp
@@ -45,7 +45,9 @@ int main(int ac, char *av[])
return 3;
LibRaw rp;
rp.imgdata.params.output_tiff = 1;
- int ret = rp.open_bayer(buffer, fsz, 640, 480, 0, 0, 0, 0, 0, LIBRAW_OPENBAYER_RGGB, 0, 0, 1400);
+ rp.imgdata.params.no_auto_bright = 1;
+ //int ret = rp.open_bayer(buffer, fsz, 640, 480, 0, 0, 0, 0, 0, LIBRAW_OPENBAYER_RGGB, 0, 0, 1400);
+ int ret = rp.open_bayer(buffer, fsz,4112,3008,0,0,0,0,0,LIBRAW_OPENBAYER_RGGB,0,0,0);
if (ret != LIBRAW_SUCCESS)
return 4;
if ((ret = rp.unpack()) != LIBRAW_SUCCESS)

(no_auto_bright=1 added to default settings).

Here is TIFF produced from your sample (screenshot in viewer): https://www.dropbox.com/s/alm7jqumy7fmf12/Screenshot%202017-08-02%2019.1...