diff --git a/CMakeLists.txt b/CMakeLists.txt
index dfe7b12e..c770d906 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,6 +6,7 @@ option(MOMO_ENABLE_AVX2 "Enable AVX2 support" ON)
 option(MOMO_ENABLE_SANITIZER "Enable sanitizer" OFF)
 option(MOMO_ENABLE_CLANG_TIDY "Enable clang-tidy checks" OFF)
 option(MOMO_ENABLE_RUST_CODE "Enable code parts written in rust" ON)
+option(MOMO_EMSCRIPTEN_MEMORY64 "Enable memory 64 support for emscripten builds" OFF)
 option(MOMO_EMSCRIPTEN_SUPPORT_NODEJS "Enable Node.js filesystem for emscripten compilation" OFF)
 option(MOMO_BUILD_AS_LIBRARY "Configure and Build the emulator as a shared library (without the samples and tests)" OFF)
 
diff --git a/cmake/compiler-env.cmake b/cmake/compiler-env.cmake
index cb7da226..8cd65263 100644
--- a/cmake/compiler-env.cmake
+++ b/cmake/compiler-env.cmake
@@ -123,12 +123,26 @@ if(CMAKE_SYSTEM_NAME MATCHES "Emscripten")
     $<$<CONFIG:Debug>:-sASSERTIONS>
     -sWASM_BIGINT
     -sUSE_OFFSET_CONVERTER
-    -sMAXIMUM_MEMORY=4gb
     #-sEXCEPTION_CATCHING_ALLOWED=[..]
     -sEXIT_RUNTIME
     -sASYNCIFY
   )
 
+  if(MOMO_EMSCRIPTEN_MEMORY64)
+    momo_add_c_and_cxx_compile_options(
+      -sMEMORY64
+    )
+
+    add_link_options(
+      -sMAXIMUM_MEMORY=8gb
+      -sMEMORY64
+    )
+  else()
+    add_link_options(
+      -sMAXIMUM_MEMORY=4gb
+    )
+  endif()
+
   if(MOMO_EMSCRIPTEN_SUPPORT_NODEJS)
     add_link_options(
       -lnodefs.js -sNODERAWFS=1
diff --git a/deps/unicorn b/deps/unicorn
index e9492203..1cdd062a 160000
--- a/deps/unicorn
+++ b/deps/unicorn
@@ -1 +1 @@
-Subproject commit e9492203a1c6c7661534cce6cb883a808e611d9e
+Subproject commit 1cdd062a453c22c7bbd8dc9000efc29d4f3e4a38
diff --git a/src/debugger/message_transmitter.cpp b/src/debugger/message_transmitter.cpp
index 2e358fbf..a602d649 100644
--- a/src/debugger/message_transmitter.cpp
+++ b/src/debugger/message_transmitter.cpp
@@ -33,7 +33,7 @@ namespace debugger
             var message = getMessageFromQueue();
             if (!message || message.length == 0)
             {
-                return null;
+                return 0;
             }
 
             const length = lengthBytesUTF8(message) + 1;