Ex43 stdlib errors

I’m trying to go through the stats engine, which shouldn’t be very complicated, and I’ve checked that my code is right. But when I run make, I get the following:

https://pastebin.com/6EnwgMHe

The trace mentions my code once, so what the heck do I do? I’ve never had a problem including stdlib.h before. Has this happened to anyone else?

Versions:
glibc: 2.35
GNU make: 4.3
cc: 12.1.0

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