Exiv2

$1136 rmills@rmillsmbp:~/gnu/exiv2/trunk $ cp test/data/Reagan.jpg  .
1137 rmills@rmillsmbp:~/gnu/exiv2/trunk $ exiv2 --comment 'hello world' Reagan.jpg 
1138 rmills@rmillsmbp:~/gnu/exiv2/trunk $ exiv2 --comment 'hello world' Reagan.jpg 
1139 rmills@rmillsmbp:~/gnu/exiv2/trunk $ exiv2 --comment 'hello world' Reagan.jpg 
Warning: JPEG format error, rc = 5
Exiv2 exception in modify action for file Reagan.jpg:
Input data does not contain a valid image
1140 rmills@rmillsmbp:~/gnu/exiv2/trunk $ 

I believe this has been introduced by the modification to src/jpgimage.cpp/doWriteMetadata() to handle ICC profiles. I haven't totally understood the variable comPos which determined the chunk index at which to write the comment. The comment is being written to output at the wrong time and thereby corruption the chain of chunks.

Remarkably, this isn't being detected by the test suite. When I fix it, I'll add a regression detector to test/icc-test.sh.