diff --git a/32blit-config.cmake b/32blit-config.cmake
index 019cfe196..657666c40 100644
--- a/32blit-config.cmake
+++ b/32blit-config.cmake
@@ -24,7 +24,7 @@ if (NOT DEFINED BLIT_ONCE)
 	if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
 		set(CMAKE_BUILD_TYPE "Release")
 	endif()
-	
+
 	if(WIN32)
 		add_definitions("-DWIN32")
 	endif()
@@ -36,7 +36,14 @@ if (NOT DEFINED BLIT_ONCE)
 		set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/${FILE})
 
 		# get the inputs/outputs for the asset tool (at configure time)
-		execute_process(COMMAND ${PYTHON_EXECUTABLE} -m ttblit --debug cmake --config ${CMAKE_CURRENT_SOURCE_DIR}/${FILE} --output ${CMAKE_CURRENT_BINARY_DIR} --cmake ${CMAKE_CURRENT_BINARY_DIR}/assets.cmake)
+		execute_process(
+		    COMMAND ${PYTHON_EXECUTABLE} -m ttblit --debug cmake --config ${CMAKE_CURRENT_SOURCE_DIR}/${FILE} --output ${CMAKE_CURRENT_BINARY_DIR} --cmake ${CMAKE_CURRENT_BINARY_DIR}/assets.cmake
+            RESULT_VARIABLE TOOL_RESULT
+		)
+		if(${TOOL_RESULT})
+		    message(FATAL_ERROR "Reading asset config failed!\n")
+		endif()
+
 		include(${CMAKE_CURRENT_BINARY_DIR}/assets.cmake)
 
 		# do asset packing (at build time)
diff --git a/32blit-sdl/CMakeLists.txt b/32blit-sdl/CMakeLists.txt
index d9e6b26d9..373cbcdcd 100644
--- a/32blit-sdl/CMakeLists.txt
+++ b/32blit-sdl/CMakeLists.txt
@@ -237,7 +237,14 @@ function(blit_metadata TARGET FILE)
 	set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS ${FILE})
 
 	# parse the metadata to variables
-	execute_process(COMMAND ${PYTHON_EXECUTABLE} -m ttblit cmake --config ${FILE} --cmake ${CMAKE_CURRENT_BINARY_DIR}/metadata.cmake)
+	execute_process(
+		COMMAND ${PYTHON_EXECUTABLE} -m ttblit cmake --config ${FILE} --cmake ${CMAKE_CURRENT_BINARY_DIR}/metadata.cmake
+		RESULT_VARIABLE TOOL_RESULT
+	)
+	if(${TOOL_RESULT})
+		message(FATAL_ERROR "Reading metadata config failed!\n")
+	endif()
+
 	include(${CMAKE_CURRENT_BINARY_DIR}/metadata.cmake)
 
 	if(APPLE)
diff --git a/32blit-stm32/executable.cmake b/32blit-stm32/executable.cmake
index a831d0f85..da8ff39bf 100644
--- a/32blit-stm32/executable.cmake
+++ b/32blit-stm32/executable.cmake
@@ -56,7 +56,14 @@ function(blit_metadata TARGET FILE)
 	set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS ${FILE})
 
 	# get the inputs/outputs for the asset tool (at configure time)
-	execute_process(COMMAND ${PYTHON_EXECUTABLE} -m ttblit cmake --config ${FILE} --cmake ${CMAKE_CURRENT_BINARY_DIR}/metadata.cmake)
+	execute_process(
+		COMMAND ${PYTHON_EXECUTABLE} -m ttblit cmake --config ${FILE} --cmake ${CMAKE_CURRENT_BINARY_DIR}/metadata.cmake
+		RESULT_VARIABLE TOOL_RESULT
+	)
+	if(${TOOL_RESULT})
+		message(FATAL_ERROR "Reading metadata config failed!\n")
+	endif()
+
 	include(${CMAKE_CURRENT_BINARY_DIR}/metadata.cmake)
 
 	if(${CMAKE_VERSION} VERSION_LESS "3.15.0")