-125 being MEMORY_E does point strongly to heap exhaustion during certificate parsing. Besides WOLFSSL_SMALL_CERT_VERIFY fnf game, you may also want to check certificate size and whether USE_FAST_MATH is increasing RAM usage too much for the TM4C129X.
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ReferencesStable Releases - download stable product releases.
Development Branch - latest development branch on GitHub.
wolfSSL Manual - wolfSSL (formerly CyaSSL) product manual and API reference.