nu.&I8<];
z{mʗ{V
z{S}ĝ xjǺHi Romiras,
Yes, as you pointed, The trap in Kernel.Next.
It read the empty block.tag(=0).size.
Though the Kernel.root is HeapAlloc'ed at Kernel.Init, but it have not alloc
any typed block,when you alloc a big size array,the NewArr will call
FastCollect,then MarkLocals->CheckCandidates->Next .
the simple solution is add a guard:
IF S.VAL(INTEGER,blk.tag)DIV 4 * 4 =0 THEN RETURN END;
after
blk := S.VAL(Block, S.VAL(INTEGER, c) + 12);
in CheckCandidates, Sweep proc;
another: if you dont modify Kernel,your can alloc a small array before alloc big, that will work.
Wish Marc give a completed solution
Regards
luowy
----- ?? -----
???: Romiras
? ?: Re: [BLACKBOX] FW: [BLACKBOX] Windows 7
? ?: 2012?9?3? 7:05:48
I still can reproduce a memory allocation bug with following code:
MODULE TestNewArr;
PROCEDURE Do*;
VAR ptr : POINTER TO ARRAY OF REAL;
BEGIN
NEW(ptr, 07FFCH);
END Do;
BEGIN
Do
END TestNewArr.
I have compiled a new Kernel and then builded test console application by command
DevLinker.Link dos testalloc.exe := Kernel$+ TestNewArr~
It failes in CheckCandidates. But if I use an original (CP) version of procedure Next, I get error from it: "illegal memory read [ad = 00000000]". Tested on Windows XP SP3 in both physical machine with 2GB and virtual machine with 384MB RAM. Same bug when running testalloc under Wine in Linux.
nu.&I8<];
z{mʗbqb
z{m}ޝ xjǺ
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\uc1\pard\plain\deftab360 \f0\fs20 Hi Romiras,\par
\par
Yes, as you pointed, The trap in Kernel.Next.\par
It read the empty block.tag(=0).size.\par
\par
Though the Kernel.root is HeapAlloc'ed at Kernel.Init, but it have not alloc \par
any typed block,when you alloc a big size array,the NewArr will call\par
FastCollect,then MarkLocals->CheckCandidates->Next .\par
\par
\par
the simple solution is add a guard:\par
\par
IF S.VAL(INTEGER,blk.tag)DIV 4 * 4 =0 THEN RETURN END;\par
after \par
blk := S.VAL(Block, S.VAL(INTEGER, c) + 12); \par
\par
in CheckCandidates, Sweep proc;\par
\par
\par
another: if you dont modify Kernel,your can alloc a small array before alloc big, that will work.\par
\par
\par
Wish Marc give a completed solution\par
\par
\par
Regards\par
\par
luowy\par
\par
----- ?? ----- \par
???: Romiras \par
? ?: Re: [BLACKBOX] FW: [BLACKBOX] Windows 7\par
? ?: 2012?9?3? 7:05:48\par
\par
I still can reproduce a memory allocation bug with following code:\par
\par
MODULE TestNewArr;\par
\par
PROCEDURE Do*;\par
VAR ptr : POINTER TO ARRAY OF REAL;\par
BEGIN\par
\par
NEW(ptr, 07FFCH);\par
END Do;\par
\par
BEGIN\par
Do\par
END TestNewArr.\par
\par
I have compiled a new Kernel and then builded test console application by command\par
DevLinker.Link dos testalloc.exe := Kernel$+ TestNewArr~\par
\par
It failes in CheckCandidates. But if I use an original (CP) version of procedure Next, I get error from it: "illegal memory read [ad = 00000000]". Tested on Windows XP SP3 in both physical machine with 2GB and virtual machine with 384MB RAM. Same bug when running testalloc under Wine in Linux}}nu.&I8<];
Received on Mon Sep 03 2012 - 09:41:20 UTC