simplified tcc_debug0.c even further.

tcc_debug1.c

#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

typedef struct TFrame TFrame;
struct TFrame {
  TFrame* prev;
  char *procname;
  int64_t line;
  char *filename;
  int16_t len;
  int16_t calldepth;
};

typedef struct anontuple {
    uint8_t Field0;
} anontuple;

TFrame *frameptr = NULL;

void nimFrame(TFrame *s) {
    s->calldepth = (!frameptr) ? 0 : frameptr->calldepth+1;
    s->prev = frameptr;
    frameptr = s;
    if (s->calldepth == 2000) {
        printf("stackoverfloaw!");
        exit(1);
    }
}

static void popFrame(void) {
    frameptr = (*frameptr).prev;
}

static anontuple split() {
    TFrame FR;
    nimFrame(&FR);
    anontuple result0 = {0};
    popFrame();
    return result0;
}

static anontuple f4() {
    TFrame FR;
    nimFrame(&FR);
    anontuple result0;
    result0 = split();
    popFrame();
    return result0;
}

static anontuple f3() {
    TFrame FR;
    nimFrame(&FR);
    anontuple result0;
    result0 = f4();
    popFrame();
    return result0;
}

void main() {
    anontuple temp = f3();
    printf("%x, %x\n", temp.Field0);
}