On 4.1 and 4.0 the following program gets a segmentation fault on x86 (tested
with 4.1.0 20050318 ) and x86_64 (tested with 4.1.0 20050321 and 4.0.0
20050320).
$ cat z
with P1; use P1;
procedure PP is
A : constant E := Get ("3");
begin
if A /= Enum_3 then
raise Program_Error;
end if;
end PP;
package P1 is
type E is (Enum_1,Enum_2,Enum_3);
function Get (Y : in String) return E;
end P1;
package body P1 is
type Ptr is access constant String;
type T is array (E) of Ptr;
X : constant T :=
(Enum_1 => new String'("1"),
Enum_2 => new String'("2"),
Enum_3 => new String'("3"));
function Get (Y : in String) return E is
begin
for I in X'Range loop
if X (I).all = Y then
return I;
end if;
end loop;
return Enum_1;
end Get;
end P1;
$ gnatchop z
$ gnatmake pp
$ ./pp
Segmentation fault
$
We expect no output.
gdb backtrace
Program received signal SIGSEGV, Segmentation fault.
0x000000000040239f in p1.get (y={P_ARRAY = 0x407f5c, P_BOUNDS = 0x407f54}) at
p1.adb:12
12 if X (I).all = Y then
Current language: auto; currently minimal
(gdb) bt
#0 0x000000000040239f in p1.get (y={P_ARRAY = 0x407f5c, P_BOUNDS = 0x407f54})
at p1.adb:12
#1 0x00000000004025c3 in _ada_pp () at pp.adb:3
#2 0x0000000000401f4b in main (argc=1, argv=548682068712, envp=548682068728) at
b~pp.adb:114
Not investigated yet, found in my own test code.
This code was working with 3.3.3 and probably all previously released versions
of GCC. This was already failing on 4.0.0 20041214 so it's not brand new.
--
Summary: Simple array of string access miscompiled on x86 and
x86_64
Product: gcc
Version: 4.1.0
Status: UNCONFIRMED
Keywords: wrong-code
Severity: normal
Priority: P2
Component: ada
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: laurent at guerby dot net
CC: gcc-bugs at gcc dot gnu dot org,kenner at vlsi1 dot
ultra dot nyu dot edu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20593
