[Ada] Secondary stack leak due to controlled component
This pach modifies the expansion related to initialization calls and secondary stack usage to inspec the components of a type derived from Limited_Controlled or Controlled. Previously controlled types were treated as never utilizing the secondary stack, however this is not true because a controlled type may contain a component initialized by a function which returns on the secondary stack. ------------ -- Source -- ------------ -- pack1.ads with Ada.Finalization; use Ada.Finalization; package Pack1 is type Ctrl is new Controlled with record Comp : Integer; end record; function Make_Ctrl return Ctrl; end Pack1; -- pack1.adb package body Pack1 is Empty : constant Ctrl := (Controlled with Comp => 123); function Make_Ctrl return Ctrl is begin return Empty; end Make_Ctrl; end Pack1; -- pack2.ads with Ada.Finalization; use Ada.Finalization; with Pack1; use Pack1; package Pack2 is type Ctrl_Wrap is new Controlled with record Comp : Ctrl := Make_Ctrl; end record; end Pack2; -- main.adb with Pack2; use Pack2; procedure Main is procedure Make_Ctrl_Wrap is Obj : Ctrl_Wrap; pragma Warnings (Off, Obj); begin null; end Make_Ctrl_Wrap; begin for Iter in 1 .. 10_000 loop Make_Ctrl_Wrap; end loop; end Main; ---------------------------- -- Compilation and output -- ---------------------------- $ gnatmake -q main.adb $ valgrind ./main >& valgrind.log $ grep -c "still reachable" valgrind.log 0 2018-01-11 Hristian Kirtchev <kirtchev@adacore.com> gcc/ada/ * sem_res.adb (Uses_SS): A controlled type requires the secondary stack if it contains at least one component declaration employing a function call returning on the secondary stack. From-SVN: r256499
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