It appears there's a couple of bugs in the transient initialization code which is causing (at least) my version of handmade to crash (both days 85 & 86).
 | transient_state *TranState = (transient_state *)Memory->TransientStorageSize;
  
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Should be:
 | transient_state *TranState = (transient_state *)Memory->TransientStorage;
  
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And:
 | InitializeArena(&TranState->TranArena, Memory->TransientStorageSize - sizeof(transient_state), (uint8 *)Memory->TransientStorageSize + sizeof(transient_state));
  
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Should be:
 | InitializeArena(&TranState->TranArena, Memory->TransientStorageSize - sizeof(transient_state), (uint8 *)Memory->TransientStorage + sizeof(transient_state));
  
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