Bug: Invalid Pointer Dereference for 3D Arrays; for 2D arrays Pointer Dereference is ok

[Yeaseen]

Giving CxGo a hard time to explore this tool.

Source C code:

#include <stdio.h>
int main() {
    int array3D[3][3][3];
    int (*pArray3D)[3][3] = array3D;
    int i, j, k;
    for ( i = 0; i < 3; i++) {
        for (j = 0; j < 3; j++) {
            for (k = 0; k < 3; k++) {
                *(*(*(pArray3D + i) + j) + k) = 5;
            }
        }
    }
    printf("Test: %.d\n", pArray3D[0][0][0]);
    return 0;
}

Translated Go Code

package main

import (
	"github.com/gotranspile/cxgo/runtime/stdio"
	"os"
	"unsafe"
)

func main() {
	var (
		array3D  [3][3][3]int
		pArray3D *[3][3]int = (*[3][3]int)(unsafe.Pointer(&array3D[0][0][0]))
		i        int
		j        int
		k        int
	)
	for i = 0; i < 3; i++ {
		for j = 0; j < 3; j++ {
			for k = 0; k < 3; k++ {
				*unsafe.Pointer(uintptr((*((*[3][3]int)(unsafe.Add(unsafe.Pointer(pArray3D), unsafe.Sizeof([3][3]int{})*uintptr(i)))))[j][0] + k)) = 5
			}
		}
	}
	stdio.Printf("Test: %.d\n", (*(*[3][3]int)(unsafe.Add(unsafe.Pointer(pArray3D), unsafe.Sizeof([3][3]int{})*0)))[0][0])
	os.Exit(0)
}

Go build Failure

./runner.go:20:6: invalid operation: cannot indirect unsafe.Pointer(uintptr((*((*[3][3]int)(unsafe.Add(unsafe.Pointer(pArray3D), unsafe.Sizeof([3][3]int{}) * uintptr(i)))))[j][0] + k)) (value of type unsafe.Pointer)

Root Cause:

Invalid Pointer dereferencing for 3D arrays. But, for 2D array version of the source C code, CxGo pdouces correct Go code.

Modification that worked

package main

import (
	"github.com/gotranspile/cxgo/runtime/stdio"
	"os"
	"unsafe"
)

func main() {
	var (
		array3D  [3][3][3]int
		pArray3D *[3][3]int = (*[3][3]int)(unsafe.Pointer(&array3D[0][0][0]))
		i        int
		j        int
		k        int
	)
	for i = 0; i < 3; i++ {
		for j = 0; j < 3; j++ {
			for k = 0; k < 3; k++ {
                               //derefencing has been modified here
				(*(*[3][3]int)(unsafe.Add(unsafe.Pointer(pArray3D), unsafe.Sizeof([3][3]int{})*uintptr(i))))[j][k] = 5
			}
		}
	}
	stdio.Printf("Test: %.d\n", (*(*[3][3]int)(unsafe.Add(unsafe.Pointer(pArray3D), unsafe.Sizeof([3][3]int{})*0)))[0][0])
	os.Exit(0)
}