RE: How can I determine why gdb throws unknown exceptions when debugging programs with threads on my Cygwin installation?

["Jay P. Elston" <jay dot elston at oemgroupinc dot com>]

On October 25, 2019 6:48 AM, Michael Soegtrop wrote:

>It has been reported in the past that antivirus software from Trend Micro result in STATUS_GUARD_PAGE_VIOLATION in ntdll!RtlAllocateHeap ().

>See: http://cygwin.1069669.n5.nabble.com/XWin-startup-crash-x86-64-Windows-10-td126544.html#a126561

On the advice of Jon Turney, I ran a "bt f" command after gdb caught the exception, and it appears that a Trend Micro dll  (TmUmEvt64.dll) is where the error occurs:

Thread 7 received signal ?, Unknown signal.
[Switching to Thread 8736.0x2bf4]
0x0000000077947b97 in ntdll!RtlAllocateHeap ()
   from /cygdrive/c/Windows/SYSTEM32/ntdll.dll
(gdb) bt f
#0  0x0000000077947b97 in ntdll!RtlAllocateHeap ()
   from /cygdrive/c/Windows/SYSTEM32/ntdll.dll
No symbol table info available.
#1  0x00000000779f233d in ntdll!EtwEventWriteStartScenario ()
   from /cygdrive/c/Windows/SYSTEM32/ntdll.dll
No symbol table info available.
#2  0x00000000779f3014 in ntdll!EtwEventWriteStartScenario ()
   from /cygdrive/c/Windows/SYSTEM32/ntdll.dll
No symbol table info available.
#3  0x0000000077947b9c in ntdll!RtlAllocateHeap ()
   from /cygdrive/c/Windows/SYSTEM32/ntdll.dll
No symbol table info available.
#4  0x000007fefd2e1c68 in TmmonDestoryAddonObject ()
   from /cygdrive/c/Windows/system32/tmumh/20019/AddOn/8.20.0.1028/TmUmEvt64.dll
No symbol table info available.
#5  0x000007fefd2267ab in ?? ()
   from /cygdrive/c/Windows/system32/tmumh/20019/AddOn/8.20.0.1028/TmUmEvt64.dll
No symbol table info available.
#6  0x000007fefd2a551a in TmmonDestoryAddonObject ()
   from /cygdrive/c/Windows/system32/tmumh/20019/AddOn/8.20.0.1028/TmUmEvt64.dll

This is not a Cygwin problem -- the solution is to be to add the Cygwin bin directory to Trend Micro's exception list. I will give this a try
after I get our IT department to do this.