[Bug 49549] New: winetricks -q dotnet45 leaves dozens of mscorsvw.exe processes

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=49549

Bug ID: 49549
           Summary: winetricks -q dotnet45 leaves dozens of mscorsvw.exe
                    processes
           Product: Wine
           Version: 5.12
          Hardware: x86
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: -unknown
          Assignee: [e-mail]
          Reporter: [e-mail]
                CC: [e-mail]
   Regression SHA1: 72fc2ceaa6ae472a809b4d5c02be98c44388c1b7
      Distribution: Debian

In addition to hanging in as yet undetermined circumstances -- bug 49532 --
with 5.12 'winetricks -q dotnet45' when apparently successful results in dozens
of mscorsvw.exe processes hanging around. Checked just now with a fresh 32-bit
prefix. Sample from ps auxww:

spoon    14633  0.7  0.8 1816076 97364 ?       S    22:21   0:00
C:\windows\Microsoft.NET\Framework\v4.0.30319\mscorsvw.exe -StartupEvent 3b0
-InterruptEvent c4 -NGENProcess c8 -Pipe 38c -Comment NGen Worker Process

Regression test yielded:

72fc2ceaa6ae472a809b4d5c02be98c44388c1b7 is the first bad commit
commit 72fc2ceaa6ae472a809b4d5c02be98c44388c1b7
Author: Alexandre Julliard 
Date:   Fri Jul 3 12:02:58 2020 +0200

ntdll: Use pthread mutexes for uninterrupted sections in the Unix library.

Signed-off-by: Alexandre Julliard

:040000 040000 e0a62fd390db2e0bc73f661747c6425402318a5a
829a56e7996c90891205b46b94a05188c442b934 M    dlls

...and a day or two ago I was able to revert that commit and have things work.
There's some conflict now though.