diff --git a/src/alloc.c b/src/alloc.c
index a51d93b1..6b6c5945 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -302,8 +302,8 @@ static void _mi_show_block_trace(const mi_page_t* page, const mi_block_t* block,
 
 static const mi_block_t* mi_block_predecessor(const mi_page_t* page, const mi_block_t* block) {
   const size_t bsize = page->xblock_size;
-  mi_assert_internal(bsize > 0);
-  if (bsize >= MI_HUGE_BLOCK_SIZE) return NULL;
+  mi_assert_internal(bsize > 0 || page->used == 0);
+  if (bsize == 0 /* if page is freed */|| bsize >= MI_HUGE_BLOCK_SIZE) return NULL;
   const mi_block_t* prev = (const mi_block_t*)((uint8_t*)block - bsize);
   uint8_t* pstart = _mi_segment_page_start(_mi_page_segment(page), page, NULL);
   if (pstart > (uint8_t*)prev) return NULL;
diff --git a/test/main-override-static.c b/test/main-override-static.c
index b22e996e..5887b388 100644
--- a/test/main-override-static.c
+++ b/test/main-override-static.c
@@ -27,15 +27,15 @@ int main() {
   mi_version();
   mi_stats_reset();
   // detect double frees and heap corruption
-  double_free1();
+  // double_free1();
   // double_free2();
-  // double_free3();
+  double_free3();
   // corrupt_free1();
   // corrupt_free2();
   // block_overflow1();
   // block_overflow2();
   // test_aslr();
-  invalid_free();
+  // invalid_free();
   // test_reserved();
   // negative_stat();
   // alloc_huge();