Regression: Cygwin 3.5.1 freezes when launching several mingw processes in parallel

[jojelino]

$ (gdb|grep '+1275' -n -B10 -A10)<<EOF
symbol cygwin1.dll
target exec cygwin1.dll
disass/m _pinfo::set_ctty(fhandler_termios*, int)
EOF

warning: the current range check setting does not match the language.

530     /usr/src/debug/cygwin-3.5.1-1/winsup/cygwin/pinfo.cc: No such 
file or directory.
225-
226-564 in /usr/src/debug/cygwin-3.5.1-1/winsup/cygwin/pinfo.cc
227-565 in /usr/src/debug/cygwin-3.5.1-1/winsup/cygwin/pinfo.cc
228-   0x00000001800991de <+300>:       mov    0x10(%rdx),%edi
229-   0x00000001800991e1 <+303>:       test   %edi,%edi
230-   0x00000001800991e3 <+305>:       jne    0x1800991f1 
<_pinfo::set_ctty(fhandler_termios*, int)+319>
231-
232-566 in /usr/src/debug/cygwin-3.5.1-1/winsup/cygwin/pinfo.cc
233-   0x00000001800991cc <+282>:       mov    (%rbx),%eax
234-   0x00000001800991e5 <+307>:       cmp    %eax,0xfc20(%rbx)
235:   0x00000001800991eb <+313>:       je     0x1800995ad 
<_pinfo::set_ctty(fhandler_termios*, int)+1275>
236-
237-567 in /usr/src/debug/cygwin-3.5.1-1/winsup/cygwin/pinfo.cc
238-568 in /usr/src/debug/cygwin-3.5.1-1/winsup/cygwin/pinfo.cc
239-569 in /usr/src/debug/cygwin-3.5.1-1/winsup/cygwin/pinfo.cc
240-570 in /usr/src/debug/cygwin-3.5.1-1/winsup/cygwin/pinfo.cc
241-   0x00000001800991ce <+284>:       cmpb   $0x0,0x1ad535(%rip) 
  # 0x18024670a <cygwin_finished_initializing>
242-   0x00000001800991d5 <+291>:       jne    0x1800991f1 
<_pinfo::set_ctty(fhandler_termios*, int)+319>
243-   0x00000001800995e6 <+1332>:      call   0x180205fa8 
<IsDebuggerPresent>
244-   0x00000001800995eb <+1337>:      test   %eax,%eax
245-   0x00000001800995ed <+1339>:      nopl   (%rax)

On 3/1/2024 8:57 AM, jojelino via Cygwin wrote:
> Line 74 of 
> "/usr/src/debug/cygwin-3.5.1-1/winsup/cygwin/local_includes/tty.h"
>     starts at address 0x1800995ad <_pinfo::set_ctty(fhandler_termios*, 
> int)+1275> and ends at 0x1800995bb <_pinfo::set_ctty(fhandler_termios*, 
> int)+1289>.