This bug is upstream bug #134 [1]. I've attached the patch that fixed it and
also tested it working.
[1] http://bugzilla.rawstudio.org/show_bug.cgi?id=134
Index: src/rawstudio.c
===================================================================
--- src/rawstudio.c (revisione 1440)
+++ src/rawstudio.c (revisione 1441)
@@ -648,13 +648,13 @@
rs_photo_open_dcraw_apply_black_and_shift_mmx(dcraw_data *raw, RS_PHOTO *photo)
{
char b[8];
- gushort *sub = (gushort *) b;
+ volatile gushort *sub = (gushort *) b;
void *srcoffset;
void *destoffset;
guint x;
guint y;
gushort *src = (gushort*)raw->raw.image;
- gint64 shift = (gint64) (16.0-log((gdouble) raw->rgbMax)/log(2.0)+0.5);
+ volatile gint64 shift = (gint64) (16.0-log((gdouble) raw->rgbMax)/log(2.0)+0.5);
sub[0] = raw->black;
sub[1] = raw->black;
