[Fkt-devel] Missing initialization ?

[François Trahay]

Hi,
I have imported the lastest version of FxT in EZTrace and it looks like 
there's a problem during the initialization.

In fxt_setinfos(), we can find the following piece of code:

[...]
        if (!(fxt = calloc(1,sizeof(*fxt))))
                goto out;

        fxt_print_symbols(fxt); // added for debugging purpose
        fxt->infos.space=space;

        fxt->infos.arch = FXT_RECORD_ARCH;
[...]

fxt_print_symbols(fxt) prints the value of fxt->addresses[i]. Since fxt has 
just been initialized, fxt->addresses[i] should be NULL, but here is what the 
program prints:

addresses[0]=0x7f99725a5200{.len=0, .address=0x7f9972297c90, 
.source=0x72294000, .next=0x7f9972294280}
addresses[0]->next=0x7f9972294280{.len=-1991748779, 
.address=0x52850f04a8078b48, .source=0x48000005, .next=0x503b48108b480000}

So the problem is that addresses is not initialized. At the end of the 
program, when the trace is flushed to disk, the values of the addresses array 
is browsed, leading to various warnings/errors.

A simple fix for this problem is to add :
        if (!(fxt = calloc(1,sizeof(*fxt))))
                goto out;
 
+       memset(fxt, 0, sizeof(*fxt));
        fxt->infos.space=space;
 
        fxt->infos.arch = FXT_RECORD_ARCH;


However, this problem seems to happen only when EZTrace does nasty things 
(redefine malloc + uses OpenMPI that also tend to do crappy hacks), so I'm not 
sure whether it's FxT's fault or EZTrace's.

François