diff --git a/src/plugins/imageformats/macheif/CMakeLists.txt b/src/plugins/imageformats/macheif/CMakeLists.txt
index 6ceee54d..44fe3bd7 100644
--- a/src/plugins/imageformats/macheif/CMakeLists.txt
+++ b/src/plugins/imageformats/macheif/CMakeLists.txt
@@ -14,7 +14,7 @@ qt_internal_add_plugin(QMacHeifPlugin
     OUTPUT_NAME qmacheif
     PLUGIN_TYPE imageformats
     SOURCES
-        ../shared/qiiofhelpers.cpp ../shared/qiiofhelpers_p.h
+        ../shared/qiiofhelpers.mm ../shared/qiiofhelpers_p.h
         main.cpp
         qmacheifhandler.cpp qmacheifhandler.h
     INCLUDE_DIRECTORIES
diff --git a/src/plugins/imageformats/macjp2/CMakeLists.txt b/src/plugins/imageformats/macjp2/CMakeLists.txt
index dab50e55..4079b7c6 100644
--- a/src/plugins/imageformats/macjp2/CMakeLists.txt
+++ b/src/plugins/imageformats/macjp2/CMakeLists.txt
@@ -9,7 +9,7 @@ qt_internal_add_plugin(QMacJp2Plugin
     OUTPUT_NAME qmacjp2
     PLUGIN_TYPE imageformats
     SOURCES
-        ../shared/qiiofhelpers.cpp ../shared/qiiofhelpers_p.h
+        ../shared/qiiofhelpers.mm ../shared/qiiofhelpers_p.h
         main.cpp
         qmacjp2handler.cpp qmacjp2handler.h
     INCLUDE_DIRECTORIES
diff --git a/src/plugins/imageformats/shared/qiiofhelpers.cpp b/src/plugins/imageformats/shared/qiiofhelpers.mm
similarity index 100%
rename from src/plugins/imageformats/shared/qiiofhelpers.cpp
rename to src/plugins/imageformats/shared/qiiofhelpers.mm