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realloc fails in C : what next ?

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# 8  
Old 09-28-2010
Quote:
Originally Posted by jossojjos
Code:
[jos@faba ~]$ ulimit -m
unlimited

But you're right, the program is trying to do something ridiculous :

Code:
   k = com.npatt*com.ncatG*sizeof(double);
   if((com.fhK=(double*)realloc(com.fhK,k)) == NULL) 
    {
    printf("%d\n",k);
    error2("oom fhK");
}

Upon execution, the reported value for k is -169522176.

Thanks a lot for your suggestion, I hadn't thought about that !

jos
Is the binary you're running a 64- or 32-bit binary?

If it's 64-bit, the use of the "%d" field in that printf() statement leads me to believe the original developer had no clear understanding of the implications of using a 64-bit memory model. That printf() field should be "%ld" for a 64-bit size_t value.

The variable "k" is defined as a "size_t", isn't it?
# 9  
Old 09-28-2010
Quote:
Originally Posted by achenle
That printf() field should be "%ld" for a 64-bit size_t value.
Assuming the version of GCC is recent enough (And I assume that it is, as "Mandriva" only started shipping in late 2005, I believe), %zu (supported under C99) is also available.
# 10  
Old 09-28-2010
the "printf("%d\n",k)" part was my addition ... and indeed, I have no idea of how 32 or 64 bit architectures change that.

But anyway, k was declared as int, so the author of the program should have done a cast to size_t, I guess ?
# 11  
Old 09-28-2010
sizeof() returns a size_t type. Instead of casting k, you would do

Code:
size_t k;
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