New vector with fixed size causes crash

Question

Problem

I had a problem randomly appearing when creating a new vector (pointer) with fixed initial size.

std::vector<double> * ret = new std::vector<double>(size);

This sometimes causes my program to crash an I don't really get why ... maybe stack corruption? I didn't find any explanation on what can cause this issue on the web sadly.

Example:

Code

// <- ... Some independant code
// [size] is an unsigned int passed as parameter to the function
cout << size << endl;
std::vector<double> * ret = new std::vector<double>(size);
cout << "Debug text" << endl;
// More code ... ->

EDIT: I will update the code as soon as possible to have a clear, minimal, reproductible to have a correct question according to: How to create a Minimal, Complete, and Verifiable example

Output

100

... Then it crashes (the trace "Debug text" is not printed and the size is correct)
I tried putting the critical line of code inside a try catch as some people suggested (for memory related errors) but no exception is catched and I still get the crash.
This code is inside a function called multiple times (with various values of size, always between 1 and 1000) and sometimes the function end up witout problem, sometimes not (the value of size does not seem to have any infulence but maybe I'm wrong).

My "solution" (you can skip this part)

I adapted my code to use a pointer to vector without initial size

std::vector<double> * ret; 

and I uses push_back() instead of []. [] was quicker for my algorithm due to how the vector was filled at first (elements order is important and I get positions from external file but I still need a vector and not an array for its dynamic aspect later in code), but I adapted everything to use push_back() (less efficient in my case as I now need more iterations but nothing critical).

Question

In short: Does anyone knows what can be causing the issue OR how I can potentially track what is causing this issue?

Answer 1

Look like your program stopped crashing not because you create a vector without size, but because you use push_back(). The fact that replacing operator[] with push_back() removes your symptom points that somewhere else you access element in a vector out of bounds, corrupt your memory and suddenly get it crashed. Check your code where you access the data.

Answer 2

As you wrote it seems like you are trying to Access it using ret[...] right :-)? Sorry for my smile but this happens when you use a pointer to a vector...

If this is the case you Need to replace it with (*ret)[...]