Why gcc didn't complain about it? It is definitely an index clash.
* linux/x32/syscallent.h: Change initializer indices for empty records from
[327 ... 511] to [329 ... 511].
[326] = { 6, TD, SEN(copy_file_range), "copy_file_range" },
[327] = { 6, TD, SEN(printargs), "64:preadv2" },
[328] = { 6, TD, SEN(printargs), "64:pwritev2" },
-[327 ... 511] = { },
+[329 ... 511] = { },
/*
* x32-specific system call numbers start at 512 to avoid cache impact
* for native 64-bit operation.