UTF-8 in glibc commit messages

[Paul Eggert <eggert@cs.ucla.edu>]

Today I tried to install a glibc fix with some non-ASCII chars in the 
commit message, but sourceware.org rejected the fix with the diagnostic 
reproduced at the end of this email.

I'm puzzled by the message, as I see that existing commit messages use 
UTF-8, e.g., 41f013cef24884604c303435dd1915be2ea5c0e0's commit message 
contains the phrase "Developer’s Manual" with the same curly apostrophe 
that my proposed commit used. Has something changed recently on 
sourceware.org to reject such commits?

I assume that UTF-8 is fine in commit messages as we use it to spell 
contributors' names. I worked around this particular problem by 
ASCIIfying the quotes but I'd rather spell people's names nicely in any 
future patches. (It might make sense for the commit hook to rejects some 
troublesome Unicode characters but that's a somewhat different topic.)

Here's the diagnostic I got:

$ git push
Enumerating objects: 21, done.
Counting objects: 100% (21/21), done.
Delta compression using up to 4 threads
Compressing objects: 100% (11/11), done.
Writing objects: 100% (11/11), 3.79 KiB | 242.00 KiB/s, done.
Total 11 (delta 10), reused 0 (delta 0), pack-reused 0
remote: *** Invalid revision history for commit 
371ef6b43fcb5052444c3f0e1ec09d01c5017149:
remote: *** It contains characters not in the ISO-8859-15 charset.
remote: ***
remote: *** Below is the first line where this was detected (line 16):
remote: *** | Use code font for ‘malloc’ instead of roman font.
remote: ***                     ^
remote: ***                     |
remote: ***
remote: *** Please amend the commit's revision history to remove it
remote: *** and try again.
remote: error: hook declined to update refs/heads/master
To sourceware.org:/git/glibc.git
  ! [remote rejected]       master -> master (hook declined)
error: failed to push some refs to 'sourceware.org:/git/glibc.git'