[Ltrace-devel] nested library calls and right-hand params

[Petr Machata]

09.11.2010 01:08, Joe Damato wrote:
> On Wed, Nov 3, 2010 at 11:00 AM, Petr Machata<pmachata at redhat.com>  wrote:
>> 02.11.2010 17:49, Petr Machata wrote:
>>>
>>> The problem
>>> here is that the register set is preserved in struct Process, not in
>>> struct callstack_element, and so is overwritten when nested call appears
>>> which has right-hand parameters too.
>>
>> This is now fixed here:
>>   https://github.com/pmachata/ltrace/tree/nested
>>
>> That branch forks off this branch:
>>   https://github.com/pmachata/ltrace/tree/float
>> which fixes a problem with passing doubles in arguments and return values on
>> x86_64, and simplifies the whole argument-preserving scenario a bit.
>>
>> Both add test cases for bugs that they fix.
>
> I tried these changes on an x86 ubuntu VM and two tests failed:
>
> FAIL: func_double(3.40*, -3.40*).*= -3.40* in
> /home/joe/code/ltrace/testsuite/ltrace.main/parameters.ltrace for 0
> times ,should be 1
> FAIL:<... func_call resumed>  \"x\", \"y\") in
> /home/joe/code/ltrace/testsuite/ltrace.main/parameters.ltrace for 0
> times ,should be 1

Hmm, these are the new tests.

> The .ltrace output is below.
> func_double(0.000000, 0.000000)                  = 0.000000

> func_call(<unfinished ...>
> func_work("x")                                   =<void>
> <... func_call resumed>  "y", "Z\213\014$\211\004$\213D$\004\302\014") =<void>
> +++ exited (status 0) +++

Yep, it's broken.  The question is why :)  That's how it looked before I 
fixed it, are you sure that you rebuilt ltrace?  If yes, can you send me 
the binaries?  That is the files "parameters" and "libparameters.so" 
from testsuite/ltrace.main.  I'll need to look inside.

Thanks,
PM