Possible bug in poasm when a ret is inside an .IF

[shlomok]

Hi,
Please refer to the full post here : http://www.masm32.com/board/index.php?topic=18690.0
but to sum up:
The following code will create an exe that always crashes when using Pelle's c to assemble and link it.
After inspecting the assembly it was clear that the first "ret" e.g. the one inside the .IF is the cause

Code Select Expand


allocateUsingHeapAlloc PROC  hHeap:DWORD, dwBytes:DWORD
                   
    invoke  HeapAlloc,hHeap, HEAP_ZERO_MEMORY,dwBytes
    .if eax == NULL
        invoke  StdOut,addr generalException
        mov     eax,FALSE
        ret
    .endif
    ret

allocateUsingHeapAlloc endp


The code runs smoothly using masm32.

Thanks,

[hutch--]

Try a RETN inside the .IF block.

[dedndave]

i think that will crash, but for a different reason   :bg

[shlomok]

i think that will crash, but for a different reason   :bg

You are right, crash , different reason :)  see the screenshot.

What was the assumption behind the suggestion to use RETN?

[qWord]

it is a bug!
The folowing example has the same problem:

Code Select Expand

.686
.model flat, stdcall
option casemap :none

.code
main proc
    .if eax == 0
        ret
    .endif
    ret
main endp
end main
who will report it to pelle?

qWord

[dedndave]

i elect Erol - lol
Erol may actually be Pelle in disguise (or the other way around)   :P

i think that will crash, but for a different reason   :bg

You are right, crash , different reason :)  see the screenshot.

What was the assumption behind the suggestion to use RETN?

when you use the meumonic "RET", the assembler assumes responsibility for typing it
and, if the epilogue is enabled, it also releases the stack frame and cleans up the stack parms, as required
the actual instructions are "RETN" for NEAR PROC's and "RETF" for FAR PROC's
there is also an IRET instruction, but that one must be explicit

you might try

Code Select Expand

        RETN    8
or whatever the appropriate number is

[hutch--]

If the RET only misbehaves within an .IF block, it probably has to do with the handling within the .IF block. To isolate what is happening with 2 RET instructions I would remove the block .IF and code it manually CMP/JE etc .... This will tell you if the problem is related to the .IF handling or not.

[shlomok]

If the RET only misbehaves within an .IF block, it probably has to do with the handling within the .IF block. To isolate what is happening with 2 RET instructions I would remove the block .IF and code it manually CMP/JE etc .... This will tell you if the problem is related to the .IF handling or not.

Is this what you had in mind?

Code Select Expand


allocateUsingHeapAlloc PROC hHeap:DWORD, dwBytes:DWORD                    
invoke  HeapAlloc,hHeap, HEAP_ZERO_MEMORY,dwBytes
test eax, NULL
jnz   @F
ret
      @@:
invoke StdOut, "xxx"
ret

allocateUsingHeapAlloc endp


this does not crash.

[dedndave]

yah - i'd say it's obviously the if/else   :P

[Vortex]

Hi shlomok,

The new Poasm version 7.00.0 has the same problem. I reported it in Pelles forum.

[Vortex]

Pelle fixed the bug. You need to download Pelles Macro Assembler, Version 7.00.3 released with PellesC V7.0, Release Candidate #2

[shlomok]

Pelle fixed the bug. You need to download Pelles Macro Assembler, Version 7.00.3 released with PellesC V7.0, Release Candidate #2

Hi thanks a lot!,
The latest version available on the website is version 7.02 RC1 dated 2012-04-15.

Where did you download version 7.03?

S.

[Vortex]

Hi shlomok,

You need to download the latest Pelles C development suit containing Poasm V7.00.3 :

http://www.smorgasbordet.com/pellesc/download.htm

http://www.smorgasbordet.com/pellesc/700/setup.exe

Pelle announced a new release candidate #2

[shlomok]

Hi shlomok,

You need to download the latest Pelles C development suit containing Poasm V7.00.3 :

http://www.smorgasbordet.com/pellesc/download.htm

http://www.smorgasbordet.com/pellesc/700/setup.exe

Pelle announced a new release candidate #2

Hi Vortex,
I was using: http://www.pellesc.de/index.php?page=download&lang=en

Didn't know about the link you provided. Thanks!

I can confirm that the bug was fixed (only tested the 32 bit version on a VM). So thanks to Pelle too.

Best,

S.

[Vortex]

Hi shlomok,

I checked it now, here is the other link :

http://www.pellesc.de/index.php?page=download&lang=en&version=7.00