I recently updated to emacs 26.1. Since then, grep results are not highlighted and does not contain links to files. 'n' or 'p' gives "Moved past last grep hit" or "Moved back before first grep hit".
1. Ran emacs 26.1 with -Q option
2. Set the following variables:
(setq explicit-shell-file-name "C:/cygwin/bin/bash.exe")
(setq shell-file-name explicit-shell-file-name)
(add-to-list 'exec-path "C:/cygwin/bin")
(setq null-device "/dev/null")
3. grep -nHri --include=*.m -e "hello" c:/path/to/dir
Couldn't visit the files in the search results.
The same steps work in 25.2 version. In both versions, grep returns search results in windows path format (c:/path/to/dir/...)