be explicit about memory tracking in os.c

src/os.c

@@ -155,6 +155,7 @@ static void mi_os_prim_free(void* addr, size_t size, bool still_committed, mi_st
   mi_assert_internal((size % _mi_os_page_size()) == 0);
   if (addr == NULL || size == 0) return; // || _mi_os_is_huge_reserved(addr)
   int err = _mi_prim_free(addr, size);
+  mi_track_mem_noaccess(addr,size);
   if (err != 0) {
     _mi_warning_message("unable to free OS memory (error: %d (0x%x), size: 0x%zx bytes, address: %p)\n", err, err, size, addr);
   }
@@ -218,7 +219,12 @@ static void* mi_os_prim_alloc(size_t size, size_t try_alignment, bool commit, bo
     _mi_stat_increase(&stats->reserved, size);
     if (commit) { 
       _mi_stat_increase(&stats->committed, size); 
-      mi_track_mem_defined(p,size); // seems needed for asan (or `mimalloc-test-api` fails)
+      // seems needed for asan (or `mimalloc-test-api` fails)
+      if (*is_zero) { mi_track_mem_defined(p,size); }   
+               else { mi_track_mem_undefined(p,size); }
+    }
+    else {
+      mi_track_mem_noaccess(p,size);
     }
   }
   return p;
@@ -418,6 +424,9 @@ bool _mi_os_commit(void* addr, size_t size, bool* is_zero, mi_stats_t* tld_stats
     *is_zero = true;
     mi_assert_expensive(mi_mem_is_zero(start, csize));
   }
+  // note: the following seems required for asan (otherwise `mimalloc-test-stress` fails)
+  if (os_is_zero) { mi_track_mem_defined(start,csize); }
+             else { mi_track_mem_undefined(start,csize); }
   return true;
 }
 
@@ -439,6 +448,7 @@ static bool mi_os_decommit_ex(void* addr, size_t size, bool* needs_recommit, mi_
     _mi_warning_message("cannot decommit OS memory (error: %d (0x%x), address: %p, size: 0x%zx bytes)\n", err, err, start, csize);
   }
   mi_assert_internal(err == 0);
+  mi_track_mem_noaccess(start,csize);
   return (err == 0);
 }
 
@@ -468,6 +478,7 @@ bool _mi_os_reset(void* addr, size_t size, mi_stats_t* stats) {
   if (err != 0) {
     _mi_warning_message("cannot reset OS memory (error: %d (0x%x), address: %p, size: 0x%zx bytes)\n", err, err, start, csize);
   }
+  mi_track_mem_undefined(start,csize);
   return (err == 0);
 }
 
@@ -517,6 +528,8 @@ static  bool mi_os_protectx(void* addr, size_t size, bool protect) {
   if (err != 0) {
     _mi_warning_message("cannot %s OS memory (error: %d (0x%x), address: %p, size: 0x%zx bytes)\n", (protect ? "protect" : "unprotect"), err, err, start, csize);
   }
+  if (protect) { mi_track_mem_noaccess(start,csize); }
+          else { mi_track_mem_undefined(start,csize); }
   return (err == 0);
 }
 
@@ -639,6 +652,8 @@ void* _mi_os_alloc_huge_os_pages(size_t pages, int numa_node, mi_msecs_t max_mse
     *memid = _mi_memid_create_os(true /* is committed */, all_zero, true /* is_large */);
     memid->memkind = MI_MEM_OS_HUGE;
     mi_assert(memid->is_pinned);
+    if (all_zero) { mi_track_mem_defined(start,size); }
+             else { mi_track_mem_undefined(start,size); }
   }
   return (page == 0 ? NULL : start);
 }

src/prim/unix/prim.c

@@ -190,7 +190,11 @@ static void* unix_mmap_prim(void* addr, size_t size, size_t try_alignment, int p
     if (hint != NULL) {
       p = mmap(hint, size, protect_flags, flags, fd, 0);
       if (p==MAP_FAILED || !_mi_is_aligned(p,try_alignment)) { 
+        #if MI_TRACK_ENABLED  // asan sometimes does not instrument errno correctly?
+        int err = 0;
+        #else
         int err = errno;
+        #endif
         _mi_warning_message("unable to directly request hinted aligned OS memory (error: %d (0x%x), size: 0x%zx bytes, alignment: 0x%zx, hint address: %p)\n", err, err, size, try_alignment, hint);
       }
       if (p!=MAP_FAILED) return p;