diff --git a/compiler/src/main/pascal/runtime.arc.pas b/compiler/src/main/pascal/runtime.arc.pas
index 141cb67..ec07ae9 100644
--- a/compiler/src/main/pascal/runtime.arc.pas
+++ b/compiler/src/main/pascal/runtime.arc.pas
@@ -60,7 +60,15 @@ procedure _AbstractMethodError;
 procedure _LeakTrackerEnable;
 procedure _LeakTrackerRegister(UserPtr: Pointer; ClassName: Pointer;
   UnitName: Pointer; Line: Int64);
-procedure _libc_atexit(Fn: Pointer); external name 'atexit';
+{ Register an at-exit handler.  Uses __cxa_atexit, NOT atexit: glibc's bare
+  `atexit` lives only in the static libc_nonshared.a (it is not a dynamic export
+  of libc.so.6), so a link that does not pull that archive — as the native
+  backend's internal and external linkers do not — leaves `atexit` unresolved at
+  load time.  __cxa_atexit is a genuine dynamic libc export and resolves on
+  every link path.  Its third argument is the DSO handle; nil registers the
+  handler against the main program.  The handler is passed one (ignored) arg. }
+function _libc_cxa_atexit(Fn, Arg, DsoHandle: Pointer): Integer;
+  external name '__cxa_atexit';
 
 implementation
 
@@ -366,7 +374,7 @@ begin
   GLTTable := PChar(_BlaiseGetMem(TableSize));
   if GLTTable = nil then begin GLTEnabled := False; Exit end;
   _libc_memset(GLTTable, 0, Int64(TableSize));
-  _libc_atexit(Pointer(@_LeakTrackerReport));
+  _libc_cxa_atexit(Pointer(@_LeakTrackerReport), nil, nil);
 end;
 
 { ------------------------------------------------------------------ }