https://gcc.gnu.org/g:0f7b8a89c325babc2e4abf0097c9f26cb2569114
commit r15-6521-g0f7b8a89c325babc2e4abf0097c9f26cb2569114
Author: Eric Botcazou <ebotca...@adacore.com>
Date: Tue Dec 3 22:36:15 2024 +0100
ada: Fix double free at run time for class-wide allocation
The previous change was too aggressive and overlooked a specific case.
gcc/ada/ChangeLog:
* exp_ch4.adb (Expand_Allocator_Expression): Put back the call to
Remove_Side_Effects in the case of a function call, a class-wide
designated type and a regular storage pool.
Diff:
---
gcc/ada/exp_ch4.adb | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/gcc/ada/exp_ch4.adb b/gcc/ada/exp_ch4.adb
index 8db729f0ce92..2fc891a4e390 100644
--- a/gcc/ada/exp_ch4.adb
+++ b/gcc/ada/exp_ch4.adb
@@ -996,6 +996,22 @@ package body Exp_Ch4 is
(Loc, TagR, Underlying_Type (TagT)));
end if;
+ -- If the designated type is class-wide, then the alignment and the
+ -- controlled nature of the expression are computed dynamically by
+ -- the code generated by Build_Allocate_Deallocate_Proc, which will
+ -- thus need to remove side effects from Exp first. But the below
+ -- test on Exp needs to have its final form to decide whether or not
+ -- to generate an Adjust call, so we preventively remove them here.
+
+ if Nkind (Exp) = N_Function_Call
+ and then Is_Class_Wide_Type (DesigT)
+ and then Present (Storage_Pool (N))
+ and then not Is_RTE (Storage_Pool (N), RE_RS_Pool)
+ and then not Is_RTE (Storage_Pool (N), RE_SS_Pool)
+ then
+ Remove_Side_Effects (Exp);
+ end if;
+
-- Generate an Adjust call if the object will be moved. In Ada 2005,
-- the object may be inherently limited, in which case there is no
-- Adjust procedure, and the object is built in place. In Ada 95, the
