merge from dev-align

src/alloc-aligned.c

@@ -34,11 +34,13 @@ static mi_decl_noinline void* mi_heap_malloc_zero_aligned_at_fallback(mi_heap_t*
   size_t oversize;
   if mi_unlikely(alignment > MI_ALIGNMENT_MAX) {
     // use OS allocation for very large alignment and allocate inside a huge page (dedicated segment with 1 page)
+    // This can support alignments >= MI_SEGMENT_SIZE by ensuring the object can be aligned at a point in the 
+    // first (and single) page such that the segment info is `MI_SEGMENT_SIZE` bytes before it (so it can be found by aligning the pointer down)
     if mi_unlikely(offset != 0) {
       // todo: cannot support offset alignment for very large alignments yet
-#if MI_DEBUG > 0
+      #if MI_DEBUG > 0
       _mi_error_message(EOVERFLOW, "aligned allocation with a very large alignment cannot be used with an alignment offset (size %zu, alignment %zu, offset %zu)\n", size, alignment, offset);
-#endif
+      #endif
       return NULL;
     }
     oversize = (size <= MI_SMALL_SIZE_MAX ? MI_SMALL_SIZE_MAX + 1 /* ensure we use generic malloc path */ : size);