diff --git a/runtime/internal/lib/internal/syscall/unix/_unix/fcntl_unix.c b/runtime/internal/lib/internal/syscall/unix/_unix/fcntl_unix.cpp
similarity index 100%
rename from runtime/internal/lib/internal/syscall/unix/_unix/fcntl_unix.c
rename to runtime/internal/lib/internal/syscall/unix/_unix/fcntl_unix.cpp
diff --git a/runtime/internal/lib/internal/syscall/unix/fcntl_unix.go b/runtime/internal/lib/internal/syscall/unix/fcntl_unix.go
index 93c768d9..140c6c94 100644
--- a/runtime/internal/lib/internal/syscall/unix/fcntl_unix.go
+++ b/runtime/internal/lib/internal/syscall/unix/fcntl_unix.go
@@ -8,7 +8,7 @@ import (
 // llgo:skip fcntl
 const (
 	LLGoPackage = "link"
-	LLGoFiles   = "_unix/fcntl_unix.c"
+	LLGoFiles   = "_unix/fcntl_unix.cpp"
 )
 
 //go:linkname llgo_fcntl2 C.llgo_fcntl2