D017 - The C runtime is a behavioural section

Status: decided Date: 2026-09-26

035-libc and 037-math check the platform's C library for behaviour: calloc zeroes, qsort sorts and calls back into guest code, snprintf reports the length it would have written. memcpy, memset and memmove are not checked, because the probe defines its own.

Why: a title imports more of the C library than of any vendor subsystem, and ISO C settles every expectation, so these are positive checks with certain signatures. Checking the three functions the probe defines would measure the probe.

Rejected: treating the guest as freestanding because the probe is - leaves the largest imported surface unchecked.