diff --git a/arch/posix/include/posix_cheats.h b/arch/posix/include/posix_cheats.h
index 07ddc638ed..778eb16023 100644
--- a/arch/posix/include/posix_cheats.h
+++ b/arch/posix/include/posix_cheats.h
@@ -44,18 +44,13 @@
 #define main(...) _posix_zephyr_main(__VA_ARGS__)
 #endif
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+#if defined(__cplusplus) && defined(CONFIG_CPP_MAIN)
 /* To be able to define main() in C++ code we need to have its prototype
  * defined somewhere visibly. Otherwise name mangling will prevent the linker
  * from finding it. Zephyr assumes a void main(void) prototype and therefore
  * this will be the prototype after renaming:
  */
-void _posix_zephyr_main(void);
-
-#ifdef __cplusplus
-}
+extern "C" int _posix_zephyr_main(void);
 #endif
 
 #ifdef CONFIG_POSIX_API