https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63276
Bug ID: 63276
Summary: implicit access checking is inserted for not null
access type against pragma Suppress (Access_Check)
Product: gcc
Version: 4.9.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: ada
Assignee: unassigned at gcc dot gnu.org
Reporter: demoonlit at panathenaia dot halfmoon.jp
The compiler inserts implicit access checking for "not null" access types
against pragma Suppress (Access_Check).
example:
==== global.ads ====
package global is
type ptr is access all Integer;
pragma Suppress (Access_Check, ptr);
var : aliased Integer := 0;
ref : not null ptr := var'Access; -- this "not null" is the trigger
pragma Suppress (Access_Check, ref);
end global;
==== main.ads ====
with global;
procedure main is
begin
global.ref.all := 1;
end main;
Compile main.ads and use nm to look for inserted implicit checking
$ gcc -c -gnatB main.adb
$ nm main.o
0000000000000048 s EH_frame1
U ___gnat_rcheck_CE_Access_Check # unexpected access checking
is inserted!
0000000000000000 T __ada_main
U _global__ref
For confirmation that "not null" is the trigger, delete "not null" from
global.ads
ref : ptr := var'Access;
And recompile main.adb, use nm
$ gcc -c -gnatB main.adb
$ nm build/main.o
0000000000000018 s EH_frame1
0000000000000000 T __ada_main
U _global__ref
The access checking is removed as intended, this time.
