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* Added a lower limit on tdynamicarray block size. Certain values less than dynamicblockbasesize+alignment, e.g. 8 on x86_64, cause grow() to enter an infinite loop. Such values come e.g. from cloning tdataconstnode, which abuses blocksize argument as data size. Mantis #20929.

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git-svn-id: trunk@19873 -
This commit is contained in:
sergei 2011-12-18 22:34:56 +00:00
parent 0b655b19d9
commit aea30f9bb2
1 changed files with 8 additions and 1 deletions
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9
compiler/cclasses.pas
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@ -433,6 +433,7 @@ type
const
dynamicblockbasesize = sizeof(tdynamicblock)-sizeof(tdynamicblockdata);
mindynamicblocksize = 8*sizeof(pointer);
type
tdynamicarray = class
@ -2401,6 +2402,12 @@ end;
FFirstblock:=nil;
FLastblock:=nil;
FCurrBlockSize:=0;
{ Every block needs at least a header and alignment slack,
therefore its size cannot be arbitrarily small. However,
the blocksize argument is often confused with data size.
See e.g. Mantis #20929. }
if Ablocksize<mindynamicblocksize then
Ablocksize:=mindynamicblocksize;
FMaxBlockSize:=Ablocksize;
grow;
end;
@ -2454,7 +2461,7 @@ end;
begin
if CurrBlockSize<FMaxBlocksize then
begin
IncSize := sizeof(ptrint)*8;
IncSize := mindynamicblocksize;
if FCurrBlockSize > 255 then
Inc(IncSize, FCurrBlockSize shr 2);
inc(FCurrBlockSize,IncSize);