Subject: Port videofeedback/Unreal_Engine_SerialCOM_Plugin to UE 5.6.1
Upstream: https://github.com/videofeedback/Unreal_Engine_SerialCOM_Plugin
Upstream commit: main @ 2024-06-21 (last push)
Target engine: Unreal Engine 5.6.1 (++UE5+Release-5.6, CL 44394996)
Verified: BuildPlugin + full project build (Editor/Game/Dev/Shipping), VS 2022 BuildTools 14.38, Win10 SDK 10.0.22621, 2026-04-10

Fixes applied:

  1. SERIALCOM.uplugin — "EngineVersion": "5.1.0" -> "5.6.0"
     UE 5.6 refuses to load the plugin citing version mismatch unless this is bumped.
     Source is API-compatible with 5.6, so no code change is needed just to load it;
     the bump is purely to satisfy the editor's plugin version check.

  2. SerialCom.cpp line 276 — Chars.Pop(false) -> Chars.Pop(EAllowShrinking::No)
     TArray::Pop(bool bAllowShrinking) was deprecated in UE 5.5 and the bool overload
     was removed in UE 5.6. The replacement enum is defined in Containers/ContainersFwd.h
     and has been available since 5.5 for forward compatibility.

  3. SerialCom.cpp line 423 — if (!m_hIDComDev) false;  ->  if (!m_hIDComDev) return false;
     Pre-existing bug in upstream: the `return` keyword was missing so the early-exit
     guard was a no-op (the boolean literal was just discarded). Not a build break under
     UE 5.6, but a clear bug that was worth fixing while we were in the file.

Apply from inside a clean clone of the upstream repo:

  git clone https://github.com/videofeedback/Unreal_Engine_SerialCOM_Plugin.git
  cd Unreal_Engine_SerialCOM_Plugin/SerialCOM
  patch -p1 < /path/to/this/file

Or as a Claude shortcut from the aesthetic-computer devcontainer:

  cd /tmp && rm -rf serialcom && \
  git clone --depth=1 https://github.com/videofeedback/Unreal_Engine_SerialCOM_Plugin.git serialcom && \
  cd serialcom/SerialCOM && \
  patch -p1 < /workspaces/aesthetic-computer/false.work/patches/serialcom-ue5.6.patch

After applying, either drop SerialCOM/ into <Project>/Plugins/, or package standalone:

  "C:\Program Files\Epic Games\UE_5.6\Engine\Build\BatchFiles\RunUAT.bat" BuildPlugin \
    -Plugin="<abs>/SerialCOM/SERIALCOM.uplugin" \
    -Package="<out>" -Rocket -TargetPlatforms=Win64

--- SerialCOM-src/SerialCOM/SERIALCOM.uplugin
+++ SerialCOM/SERIALCOM.uplugin
@@ -10,7 +10,7 @@
 	"DocsURL": "https://github.com/videofeedback/Unreal_Engine_SerialCOM_Plugin",
 	"MarketplaceURL": "",
 	"SupportURL": "https://discord.ramiroslab.com/",
-	"EngineVersion": "5.1.0",
+	"EngineVersion": "5.6.0",
 	"CanContainContent": true,
 	"IsBetaVersion": true,
 	"Installed": true,
--- SerialCOM-src/SerialCOM/Source/SERIALCOM/Private/SerialCom.cpp
+++ SerialCOM/Source/SERIALCOM/Private/SerialCom.cpp
@@ -273,7 +273,7 @@
 			// when Terminator is \n, we know we're expecting lines from Arduino. But those
 			// are ended in \r\n. That means that if we found the line Terminator (\n), our previous
 			// character could be \r. If it is, we remove that from the array.
-			if (Chars.Num() > 0 && Terminator == '\n' && Chars.Top() == '\r') Chars.Pop(false);
+			if (Chars.Num() > 0 && Terminator == '\n' && Chars.Top() == '\r') Chars.Pop(EAllowShrinking::No);

 			Chars.Add(0x0);
 			break;
@@ -420,7 +420,7 @@

 bool USerialCom::WriteBytes(TArray<uint8> Buffer)
 {
-	if (!m_hIDComDev) false;
+	if (!m_hIDComDev) return false;

 	bool bWriteStat;
 	unsigned long dwBytesWritten;