Custom firmware for RealFlight and Mission planner doesn't work as per instructions

[Georacer]

Bug report

Issue details

The SITL binary for Windows that is compiled by Cygwin does not work, as per the instructions in:
https://ardupilot.org/dev/docs/sitl-with-realflight.html#using-your-code-branch-with-mission-planner-sitl-and-realflight

When Mission Planner launches the binary for simulation it reports "Failed to connect to SITL instance"

Compiling with a local Cygwin toolchain also fails with the same mode.

Relevant discussions have been reported in:

• https://discord.com/channels/674039678562861068/710994174299603055/1245286277323165738
• https://discord.com/channels/674039678562861068/797952826847920128/1245405919383388373

The workflow seems to work with the current stable release 4.5.2.

Version
Current master

Platform
[ ] All
[ ] AntennaTracker
[ ] Copter
[X] Plane
[ ] Rover
[ ] Submarine

Airframe type
Airplane, Tailsitter

Hardware type
N/A

Logs
N/A

[EShamaev]

SITL for MP got broken completely.

When selecting "Stable" all works.
When selecting "Latest" the sim opens for one seconds and closes immidiatelly without anything in messages.

P.S. Narrowed down the problem to NEW_NOTHROW

[EShamaev]

Narrowed down to exact cause by wrapper over malloc.

I am not too good at python and don't have expertise with waf system so for a quick solution following was made to solve the issue:

diff --git a/Tools/ardupilotwaf/boards.py b/Tools/ardupilotwaf/boards.py
index 5f5ce5434b..4c763aee0e 100644
--- a/Tools/ardupilotwaf/boards.py
+++ b/Tools/ardupilotwaf/boards.py
@@ -754,7 +754,7 @@ class sitl(Board):
 
         # wrap malloc to ensure memory is zeroed
         # don't do this on MacOS as ld doesn't support --wrap
-        if platform.system() != 'Darwin':
+        if platform.system() != 'Darwin' and cfg.env.DEST_OS != 'cygwin':
             env.LINKFLAGS += ['-Wl,--wrap,malloc']
         
         if cfg.options.enable_sfml:
diff --git a/libraries/AP_Common/c++.cpp b/libraries/AP_Common/c++.cpp
index 8ab798744f..4b93f26243 100644
--- a/libraries/AP_Common/c++.cpp
+++ b/libraries/AP_Common/c++.cpp
@@ -85,7 +85,7 @@ void operator delete[](void * ptr)
 }
 
 
-#if CONFIG_HAL_BOARD != HAL_BOARD_CHIBIOS
+#if CONFIG_HAL_BOARD != HAL_BOARD_CHIBIOS && CONFIG_HAL_BOARD != HAL_BOARD_SITL
 /*
   wrapper around malloc to ensure all memory is initialised as zero
   ChibiOS has its own wrapper

I hope @tridge will find a more elegant solution that will deserve a PR.