[python] Revert: collectRoots does not need to look for unaligned

pointers as they should not exist

python/port/port.cpp

@@ -123,7 +123,7 @@ void MicroPython::init(void * heapStart, void * heapEnd) {
   mp_pystack_init(pystack, &pystack[MP_ARRAY_SIZE(pystack)]);
 #endif
 
-  volatile int stackTop;
+  volatile uintptr_t stackTop;
   void * stackTopAddress = (void *)(&stackTop);
   /* We delimit the stack part that will be used by Python. The stackTop is the
    * address of the first object that can be allocated on Python stack. This
@@ -155,29 +155,12 @@ void MicroPython::registerScriptProvider(ScriptProvider * s) {
 }
 
 void MicroPython::collectRootsAtAddress(char * address, int byteLength) {
-#if __EMSCRIPTEN__
-   // All objects are aligned, as asserted.
+  /* All pointers on the stack are aligned on sizeof(void *), as asserted.
+   * This is a consequence of the alignment requireduirements of compilers as long
+   * (Cf http://www.catb.org/esr/structure-packing/). */
   assert(((unsigned long)address) % ((unsigned long)sizeof(void *)) == 0);
   assert(byteLength % sizeof(void *) == 0);
   gc_collect_root((void **)address, byteLength / sizeof(void *));
-#else
-  for (size_t i = 0; i < sizeof(void *); i++) {
-    /* Objects on the stack are not necessarily aligned on sizeof(void *),
-     * which is also true for pointers refering to the heap. MicroPython
-     * gc_collect_root expects a table of void * that will be scanned every
-     * sizeof(void *) step. So we have to scan the stack repetitively with a
-     * increasing offset to be sure to check every byte for a heap address.
-     * If some memory can be reinterpreted as a pointer in the heap, gc_collect_root
-     * will prevent the destruction of the pointed heap memory. At worst (if
-     * the interpreted pointer was in fact an unaligned object or uninitialized
-     * memory), we will just keep extra objects in the heap which is not optimal
-     * but does not cause any crash. */
-    char * addressWithOffset = address + i;
-    // Ensure to round the length to the ceiling
-    size_t lengthInAddressSize = (byteLength - i + sizeof(void *) - 1)/sizeof(void *);
-    gc_collect_root((void **)addressWithOffset, lengthInAddressSize);
-  }
-#endif
 }
 
 KDColor MicroPython::ColorParser::ParseColor(mp_obj_t input, ColorMode ColorMode){