[Bug 49462] New: uninitialized request bytes in server request launched from wine_ntoskrnl_main_loop

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=49462

Bug ID: 49462
           Summary: uninitialized request bytes in server request launched
                    from wine_ntoskrnl_main_loop
           Product: Wine
           Version: 5.11
          Hardware: x86
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: ntoskrnl
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Created attachment 67566
  --> https://bugs.winehq.org/attachment.cgi?id=67566
Configure output

Steps to reproduce

* Build latest wine (currently 13b2587d4f).  Attached my own configure output. 
See configure output for configure flags.
* Build 'int main() { return 0; }' using i686-w64-mingw-gcc
* Run this under valgrind.  Valgrind output attached.

The first error that occurs after any chkstk errors is

==7516== Syscall param write(buf) points to uninitialised byte(s)
==7516==    at 0x4219763: __libc_write (write.c:26)
==7516==    by 0x4219763: write (write.c:24)
==7516==    by 0x4858E00: send_request (server.c:206)
==7516==    by 0x4858FCD: server_call_unlocked (server.c:281)
==7516==    by 0x4859028: wine_server_call (server.c:297)
==7516==    by 0x7BC84EC3: wine_server_call (server.c:65)
==7516==    by 0x530C07A: wine_ntoskrnl_main_loop (ntoskrnl.c:886)
==7516==    by 0x4FAEA67: ServiceMain (device.c:136)
==7516==    by 0x516AB94: service_thread (service.c:1607)
==7516==    by 0x7BC89857: ??? (thread.c:169)
==7516==    by 0x7BC898BA: call_thread_func (thread.c:208)
==7516==    by 0x7BC89849: ??? (thread.c:169)