port: EterImageLib Image/TGAImage/DXTCImage verbatim (+ d3d.h ddraw shim)

-fno-strict-aliasing on the port targets: 40250 relies on MSVC's lack of
type-based alias analysis (DXTCImage reads Color8888 through DWORD*).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/port/CMakeLists.txt

@@ -43,6 +43,9 @@ endif()
 set(MT_PORT_WARNING_FLAGS)
 if(NOT MSVC)
     set(MT_PORT_WARNING_FLAGS -Wno-unknown-pragmas -Wno-format-security)
+    # MSVC does no type-based alias analysis and 40250 relies on it (DXTCImage reads a Color8888 through a
+    # DWORD*; clang -O2 then loads the colour before it is written).
+    list(APPEND MT_PORT_WARNING_FLAGS -fno-strict-aliasing)
 endif()
 target_compile_options(port_logic PUBLIC ${MT_PORT_WARNING_FLAGS})
 # 40250 headers keep `#pragma comment(lib, "d3d8.lib")` etc. verbatim; clang turns them into ELF
@@ -208,6 +211,9 @@ if(BUILD_TESTING AND CMAKE_SYSTEM_NAME STREQUAL CMAKE_HOST_SYSTEM_NAME)
     add_executable(port_input_test ${PROJECT_SOURCE_DIR}/tests/port/port_input_test.cpp)
     target_link_libraries(port_input_test PRIVATE port_platform)
     add_test(NAME port.input COMMAND $<TARGET_FILE:port_input_test>)
+    add_executable(port_eter_image_test ${PROJECT_SOURCE_DIR}/tests/port/port_eter_image_test.cpp)
+    target_link_libraries(port_eter_image_test PRIVATE port_platform)
+    add_test(NAME port.eter_image COMMAND $<TARGET_FILE:port_eter_image_test>)
 
     # MilesLib: the 40250 sound managers over the Miles emulation (platform/MilesLib/MilesAil.cpp).
     add_executable(port_miles_test ${PROJECT_SOURCE_DIR}/tests/port/port_miles_test.cpp)