polink links my code in mainCRTstartup module

[blackoil]

My program behaves abnormal, then I trace it in OllyDbg. I found a call to my code in mainCRTstartup module, just few instructions after "call 0x401000".
I use nasm to build win32 object file, then link with polink, libraries are 32bit crt.lib & kernel32.lib

[CommonTater]

Try using the  /NODEFAULTLIB  option when linking...

More details in the Pelles C help file under "Command line tools".

[blackoil]

After the call to entry point 0x00401000, it calls my other code. It looks like a bug, but I don't know whether nasm or polink.

I just used two library file: crt.lib kernel32.lib, and polink works in a separated dir

[Vortex]

Hi blackoil,

What is the entry point of your assembly module? In Poasm, you specify it like the following :

Code: [Select]

.code

start:

.
.
.

END start ; the entry point is start

It looks like that you didn't specify an entry point in your project and the default entry point in crt.lib is picked up by the linker.

[blackoil]

I use nasm (intel syntax) to produce object file. "nasm myasm.asm -f win32"
then use polink to link. "polink -machine:x86 -subsystem:console -out:myasm.exe myasm.obj crt.lib kernel32.lib"

the problematic call instruction is at 0x004160B7,  0x00413CAB should not be called.

Code: [Select]

CPU Disasm
Address   Hex dump          Command                                  Comments
00416000  /.  55            PUSH EBP
00416001  |.  89E5          MOV EBP,ESP
00416003  |.  6A FF         PUSH -1
00416005  |.  68 00804100   PUSH OFFSET 00418000
0041600A  |.  68 08614100   PUSH 00416108
0041600F  |.  64:FF35 00000 PUSH DWORD PTR FS:[0]
00416016  |.  64:8925 00000 MOV DWORD PTR FS:[0],ESP                 ; Installs SE handler 416108
0041601D  |.  83EC 0C       SUB ESP,0C
00416020  |.  53            PUSH EBX
00416021  |.  56            PUSH ESI
00416022  |.  57            PUSH EDI
00416023  |.  8965 E8       MOV DWORD PTR SS:[LOCAL.6],ESP
00416026  |.  68 00000002   PUSH 2000000                             ; /Arg1 = 2000000
0041602B  |.  E8 300C0000   CALL 00416C60                            ; \win32.00416C60
00416030  |.  59            POP ECX
00416031  |.  A3 8C914100   MOV DWORD PTR DS:[41918C],EAX
00416036  |.  E8 E5020000   CALL 00416320
0041603B  |.  85C0          TEST EAX,EAX
0041603D  |.  75 0D         JNE SHORT 0041604C
0041603F  |.  6A 01         PUSH 1                                   ; /Arg1 = 1
00416041  |.  E8 1A050000   CALL 00416560                            ; \win32.00416560
00416046  |.  59            POP ECX
00416047  |.  E9 9B000000   JMP 004160E7
0041604C  |>  C745 FC 00000 MOV DWORD PTR SS:[LOCAL.1],0
00416053  |.  E8 18050000   CALL 00416570
00416058  |.  E8 D3050000   CALL 00416630                            ; [win32.00416630
0041605D  |.  E8 1E060000   CALL 00416680                            ; [win32.00416680
00416062  |.  E8 290A0000   CALL 00416A90                            ; [win32.00416A90
00416067  |.  E8 C40A0000   CALL 00416B30                            ; [win32.00416B30
0041606C  |.  BB 84804100   MOV EBX,OFFSET 00418084
00416071  |.  81FB 84804100 CMP EBX,OFFSET 00418084
00416077  |.  73 0D         JNB SHORT 00416086
00416079  |>  FF13          /CALL DWORD PTR DS:[EBX]
0041607B  |.  83C3 04       |ADD EBX,4
0041607E  |.  81FB 84804100 |CMP EBX,OFFSET 00418084
00416084  |.^ 72 F3         \JB SHORT 00416079
00416086  |>  A1 78914100   MOV EAX,DWORD PTR DS:[419178]
0041608B  |.  50            PUSH EAX                                 ; /Arg2 => [419178] = 0
0041608C  |.  A1 74914100   MOV EAX,DWORD PTR DS:[419174]            ; |
00416091  |.  50            PUSH EAX                                 ; |Arg1 => [419174] = 0
00416092  |.  E8 69AFFEFF   CALL 00401000                            ; \win32.00401000
00416097  |.  83C4 08       ADD ESP,8
0041609A  |.  89C3          MOV EBX,EAX
0041609C  |.  BE 84804100   MOV ESI,OFFSET 00418084
004160A1  |.  81FE 84804100 CMP ESI,OFFSET 00418084
004160A7  |.  73 0D         JNB SHORT 004160B6
004160A9  |>  FF16          /CALL DWORD PTR DS:[ESI]
004160AB  |.  83C6 04       |ADD ESI,4
004160AE  |.  81FE 84804100 |CMP ESI,OFFSET 00418084
004160B4  |.^ 72 F3         \JB SHORT 004160A9
004160B6  |>  53            PUSH EBX                                 ; /Arg1
004160B7  |.  E8 EFDBFFFF   CALL 00413CAB                            ; \win32.00413CAB
004160BC  |.  59            POP ECX
004160BD  \.  EB 28         JMP SHORT 004160E7
004160BF  /.  8B45 EC       MOV EAX,DWORD PTR SS:[EBP-14]
004160C2  |.  8B00          MOV EAX,DWORD PTR DS:[EAX]
004160C4  |.  8B00          MOV EAX,DWORD PTR DS:[EAX]
004160C6  |.  8945 E4       MOV DWORD PTR SS:[EBP-1C],EAX
004160C9  |.  8B45 EC       MOV EAX,DWORD PTR SS:[EBP-14]
004160CC  |.  50            PUSH EAX
004160CD  |.  8B45 E4       MOV EAX,DWORD PTR SS:[EBP-1C]
004160D0  |.  50            PUSH EAX
004160D1  |.  E8 1A0B0000   CALL 00416BF0
004160D6  |.  83C4 08       ADD ESP,8
004160D9  \.  C3            RETN
004160DA  /.  8B65 E8       MOV ESP,DWORD PTR SS:[EBP-18]
004160DD  |.  8B45 E4       MOV EAX,DWORD PTR SS:[EBP-1C]
004160E0  |.  50            PUSH EAX                                 ; /Arg1 => [ARG.EBP-1C]
004160E1  |.  E8 7A040000   CALL 00416560                            ; \win32.00416560
004160E6  |.  59            POP ECX
004160E7  |>  8B4D F0       MOV ECX,DWORD PTR SS:[LOCAL.4]
004160EA  |.  64:890D 00000 MOV DWORD PTR FS:[0],ECX
004160F1  |.  5F            POP EDI
004160F2  |.  5E            POP ESI
004160F3  |.  5B            POP EBX
004160F4  |.  89EC          MOV ESP,EBP
004160F6  |.  5D            POP EBP
004160F7  \.  C3            RETN


[frankie]

I tried to compile this sample:

Code: [Select]

    global      _main
    extern      _printf

    section .text
_main:
    push        message
    call        _printf
    add         esp, 4
    ret
message:
    db  'Hello, World', 10, 0
Then using last nasm release I issued the following commands

Code: [Select]

nasm my asm.asm -fwin32
polink -machine:x86 -subsystem:console -out:myasm.exe myasm.obj pocrt.lib kernel32.lib
And it runs ok.
I should ask are you using a working version of nasm?
Using a subsystem console pocrt.lib looks for a 'main' symbol in your code. Have you correctly marked the assembly entry point as '_main' ? (see the sample).
Could you post a short sample (the source not the dump).

[blackoil]

NASM version is 2.09.08, compiled on Apr  6 2011

the "pocrt.lib" solution doesn't work. I am sure the main entry get called correctly, and the bad call instruction is after "call 0x00401000".

my program runs fine until I add the underline prefix to global variable & function names, for better compatible.
I tried different naming combination, with underline prefix or not, with decorated suffix or not, but it didn't work.

And I found the mainCRTstartup routine likes a template, address are calculated then filled in. Perhaps wrong address was inserted.

[blackoil]

I tried the lastest nasm, and VC98 linker. the problem persists.
There should be a bug in CRT.LIB

[blackoil]

problem solved.
Bug or incompatibility confirmed in CRT.LIB

NASM + VC98 LINKER + LIBC.LIB + KERNEL32.LIB, works fine.
NASM + POLINK + LIBC.LIB + KERNEL32.LIB, works fine, but got multiple .rdata sections with different flags warning.


Please review the source code of CRT.LIB

[Vortex]

I remembered for an explanation from Pelle about the usage of crt.lib : some initialization functions should be called at the start of the application :

http://www.movsd.com/board/index.php?topic=2670.msg21138#msg21138

A quick example :

Code: [Select]

.386
.model flat,stdcall
option casemap:none

printf      PROTO C :VARARG
__bheapinit PROTO C :VARARG
__ioinit    PROTO C :VARARG
ExitProcess PROTO :DWORD

includelib  \PellesC\lib\Win\kernel32.lib
includelib  \Pellesc\lib\crt.lib

.data

str1        db 'Pelles C run-time library test',0

.code

start:

    invoke  __bheapinit
    test    eax,eax
    jz      finish
    invoke  __ioinit

    invoke  printf,ADDR str1

finish:

    invoke  ExitProcess,0

END start


[blackoil]

I don't think that's the cause. Check the OllyDBG dump.
The bad call is after the invocation to the entry point, and my main function exits normally (I stepped into it in OllyDBG).

004160B7  |.  E8 EFDBFFFF   CALL 00413CAB                            ; \win32.00413CAB

0x00413CAB is the address of one my function entry. There should be a address translation error, and it's rare case.

[Vortex]

Hi blackoil,

Could you post here the source file and the object module?

[blackoil]

Actually I am writing my compiler http://mycompiler.forumer.com/

If you need the buggy .exe, pm me.