EInvalidOp in D2007 FillChar & Move

I'm posting here because it looks like I can blame John O'Harrow for both functions. ;)

We're using Delphi 2007 along with madExcept and we've now had two users send us bug reports showing "EInvalidOp: Invalid floating pointer operation" errors, one in System.Move and one in System.FillChar.

I've included the details in below. I don't think we mess with the FPU in our own code other than using /, *, and Trunc, though I can't rule out something in a third-party library. Any ideas what we're doing wrong?

Thanks,
Craig Peterson
Scooter Software


***** System.Move Crash **********************************************

cpu registers:
eax = 0345ed18
ebx = 00000003
ecx = 00000006
edx = 05c4f4e8
esi = 05c4f4f6
edi = 00000000
eip = 0040356e
esp = 043efd2c
ebp = 043efd88

disassembling:
[...]
00403551 3636 fild qword ptr [ecx+eax]
00403554 3637 fild qword ptr [eax]
00403556 3638 cmp ecx, 8
00403559 3639 jle loc_40356c
0040355b 3640 fild qword ptr [eax+8]
0040355e 3641 cmp ecx, $10
00403561 3642 jle loc_403569
00403563 3643 fild qword ptr [eax+$10]
00403566 3644 fistp qword ptr [edx+$10]
00403569 3646 fistp qword ptr [edx+8]
0040356c 3648 > fistp qword ptr [edx]
0040356e 3649 fistp qword ptr [ecx+edx]
00403571 3651 ret
00403598 3657 push edx
00403599 3658 fild qword ptr [eax]
004035b0 3668 fild qword ptr [ecx+eax]
004035b3 3669 fistp qword ptr [ecx+edx]
004035b6 3670 add ecx, 8
004035b9 3671 jl loc_4035b0
004035bb 3672 fistp qword ptr [edx]
004035bd 3673 pop edx
[...]

stack dump:
043efd2c ac 5e 40 00 e8 f4 c4 05 - f8 fd 3e 04 03 00 00 00 ..^@.......>.....
043efd3c d4 f9 da 03 70 50 34 01 - 4c 00 8c 00 87 09 8c 00 .....pP4.L.......
043efd4c e8 e6 b0 05 e4 09 8c 00 - 18 ed 45 03 b8 fd 3e 04 ...........E...>.
043efd5c ac 52 40 00 88 fd 3e 04 - 4c 00 8c 00 00 00 00 00 ..R@...>.L.......
043efd6c 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00 .................
043efd7c f8 fd 3e 04 a8 8b 24 05 - b0 ea 45 03 b0 fd 3e 04 ...>...$...E...>.
043efd8c 02 2d 84 00 bc 1d 84 00 - ac 7c 40 00 d8 ea c2 05 ..-.......|@.....
043efd9c 4c fe 3e 04 f0 ea c2 05 - 30 4f 84 00 f8 fd 3e 04 L.>.....0O....>.
043efdac 78 8b 24 05 5c fe 3e 04 - 46 14 8c 00 c4 fd 3e 04 x.$.\.>.F.....>.
043efdbc ac 52 40 00 5c fe 3e 04 - d0 fd 3e 04 ac 52 40 00 ..R@.\.>...>..R@.
043efdcc 5c fe 3e 04 6c fe 3e 04 - ac 52 40 00 5c fe 3e 04 \.>.l.>..R@.\.>.
043efddc d4 f9 da 03 70 50 34 01 - 4c 00 8c 00 00 00 00 00 .....pP4.L.......
043efdec 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00 .................
043efdfc 00 00 00 00 00 00 00 00 - 00 00 00 00 20 00 00 00 .................
043efe0c 00 0e f5 1b d5 df c5 01 - 04 a8 84 e6 47 b3 c8 01 .............G...
043efe1c 30 e3 66 60 53 99 c8 01 - e8 11 00 00 00 00 00 00 0.f`S...........
043efe2c 00 00 00 00 70 50 34 01 - 4c fb 6d 00 00 00 00 00 .....pP4.L.m.....
043efe3c 80 3d 8c 00 4c fe 3e 04 - 00 00 00 00 00 00 00 00 ..=..L.>.........
043efe4c 00 00 00 00 00 00 00 00 - 20 2a 1d 05 b0 ea 45 03 ..........*....E.
043efe5c 90 fe 3e 04 0c 3d 8c 00 - 8c 2a 1d 05 a8 8b 24 05 ...>..=...*....$.


***** System.FillChar Crash *******************************************

cpu registers:
eax = 03cb3b58
ebx = 03cabb68
ecx = fffffff8
edx = ffffa768
esi = 00000000
edi = 00008000
eip = 00403f3d
esp = 0419fc14
ebp = 0419fc44

disassembling:
[...]
00403f21 fld qword ptr [eax]
00403f23 fst qword ptr [edx+eax]
00403f26 fst qword ptr [edx+eax+8]
00403f2a mov ecx, eax
00403f2c and ecx, 7
00403f2f sub ecx, 8
00403f32 sub eax, ecx
00403f34 add edx, ecx
00403f36 add eax, edx
00403f38 neg edx
00403f3a > fst qword ptr [edx+eax]
00403f3d fst qword ptr [edx+eax+8]
00403f41 add edx, $10
00403f44 jl loc_403f3a
00403f46 ffree st
00403f48 ret
00403f49 nop
00403f4a nop
00403f4b nop
00403f4c test edx, edx
00403f4e jle loc_403fa0
[...]

stack dump:
0419fc14 35 74 40 00 38 3b ca 03 - 00 00 00 00 00 80 00 00 5t@.8;..........
0419fc24 60 bb ca 03 08 80 00 00 - 01 00 00 00 75 18 80 7c `...........u..|
0419fc34 00 00 00 00 00 00 00 00 - 01 00 00 00 b4 fc 19 04 .................
0419fc44 74 fc 19 04 82 74 40 00 - 54 fc 19 04 e3 7a 4d 00 t....t@.T....zM.
0419fc54 00 80 00 00 80 fc 19 04 - c0 52 40 00 74 fc 19 04 ..........R@.t...
0419fc64 9c 3a 85 00 60 14 17 01 - 38 3b ca 03 00 00 00 00 ..:..`...8;......
0419fc74 b8 fc 19 04 a3 13 85 00 - b4 fc 19 04 c4 fc 19 04 .................
0419fc84 c0 52 40 00 b8 fc 19 04 - ff ff ff ff 38 3b ca 03 ..R@.........8;..
0419fc94 60 14 17 01 00 00 00 00 - 30 3b ca 03 3b 32 40 00 `.......0;..;2@.
0419fca4 b8 fc 19 04 35 74 40 00 - 9c 3a 85 00 00 80 00 00 .....5t@..:......
0419fcb4 00 00 00 00 e0 fc 19 04 - 7f 11 85 00 00 00 00 00 .................
0419fcc4 ec fc 19 04 c0 52 40 00 - e0 fc 19 04 9c 3a 85 00 ......R@......:..
0419fcd4 08 96 1b 03 00 80 00 00 - 00 00 00 00 20 fd 19 04 .................
0419fce4 df 05 85 00 00 00 00 00 - f8 fc 19 04 c0 52 40 00 ..............R@.
0419fcf4 20 fd 19 04 30 fd 19 04 - c0 52 40 00 20 fd 19 04 .....0....R@.....
0419fd04 38 ec 21 03 d8 5d c9 03 - 9c 3a 85 00 00 00 00 00 8.!..]...:......
0419fd14 70 fd 19 00 60 14 17 01 - 00 00 00 00 98 fd 19 04 p...`...........
0419fd24 1f 66 86 00 26 0e d6 06 - 00 00 00 00 3c fd 19 04 ..f..&.......<...
0419fd34 4b 66 86 00 98 fd 19 04 - 48 fd 19 04 c0 52 40 00 Kf......H....R@.
0419fd44 98 fd 19 04 54 fd 19 04 - c0 52 40 00 98 fd 19 04 .....T....R@.....
.

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