diff --git a/programs/fileio.c b/programs/fileio.c
index d0f6afbf6..d0804a361 100644
--- a/programs/fileio.c
+++ b/programs/fileio.c
@@ -320,7 +320,6 @@ int FIO_rust_multiFilesConcatAction(int nbFilesTotal,
 /* These policy and filesystem leaves are implemented by the Rust CLI archive.
  * The declarations in fileio.h remain the C ABI shims while file-I/O
  * orchestration and diagnostics stay here. */
-int FIO_checkFilenameCollisions(const char** filenameTable, unsigned nbFiles);
 /* FIO_highbit64() is a Rust-owned scalar policy leaf. */
 unsigned FIO_highbit64(unsigned long long v);
 unsigned long long FIO_getLargestFileSize(const char** inFileNames, unsigned nbFiles);