Can someone please verify the execution trace of this?

People are saying that they have no idea what this code does
because they do not believe it conforms to c11 or c17.
typedef int (*ptr)();  // ptr is pointer to int function
00 int H(ptr x, ptr y);
01 int D(ptr x)
02 {
03   int Halt_Status = H(x, x);
04   if (Halt_Status)
05     HERE: goto HERE;
06   return Halt_Status;
07 }
08
09 int main()
10 {
11   H(D,D);
12   return 0;
13 }
In the above case a simulator is an x86 emulator that correctly emulates
at least one of the x86 instructions of D in the order specified by the
x86 instructions of D.
This may include correctly emulating the x86 instructions of H in the
order specified by the x86 instructions of H thus calling H(D,D) in
recursive simulation.
*Execution Trace*
Line 11: main() invokes H(D,D);
*keeps repeating* (unless aborted)
Line 01:
Line 02:
Line 03: simulated D(D) invokes simulated H(D,D) that simulates D(D)
*Simulation invariant*
D correctly simulated by H cannot possibly reach past its own line 03.
The key thing to note is that no D correctly simulated by any H of every
H/D pair specified by the above template ever reaches its own line 06
and halts.
--
Copyright 2024 Olcott "Talent hits a target no one else can hit; Genius
hits a target no one else can see." Arthur Schopenhauer