`git add` with unmatching case silently fails on case-insensitive file systems

["Lê Duy Quang" <leduyquang753@gmail.com>]

Good morning,

I am using Git on Windows, whose file system is case-insensitive. If the 
working tree has a file called `SourceFile.c`, for example, and I run 
`git add sourcefile.c`, I would expect either (a) Git stages 
`SourceFile.c` or (b) Git errors with "fatal: pathspec 'sourcefile.c' 
did not match any files". However, none of those actually took place; 
instead Git did not stage the file and produced no output as if the 
command had succeeded, which led me to proceed to committing without 
realizing I had missed the file.

I would like to know whether this is intended behavior or I have bumped 
into a case-sensitivity bug.

Regards,
Quang