[PATCH stable] merge: more safe detection of criss cross merge conflict between dm and r

[Yuya Nishihara]

On Wed, 01 Feb 2017 02:13:57 +0100, Mads Kiilerich wrote:
> # HG changeset patch
> # User Mads Kiilerich <mads at kiilerich.com>
> # Date 1485911430 -3600
> #      Wed Feb 01 02:10:30 2017 +0100
> # Branch stable
> # Node ID 086c37652735ca87117333fc71941bcb67b799c3
> # Parent  2d6b86cadc1039f7cf72b64c29399bebe02e7dd3
> merge: more safe detection of criss cross merge conflict between dm and r
> 
> 41f6af50c0d8 introduced handling of a crash in this case. A review comment
> suggested that it was not entirely obvious that a 'dm' always would have a 'r'
> for the source file.
> 
> To mitigate that risk, make the code more conservative and make less
> assumptions.

Queued this for more obvious safety, thanks.