C: Array initialization segfaults depending on size and call to printf() -

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another student asked me wrong c code. reproduced erroneous behavior , have no idea why segfaults. consider tiny c programm:

#include <stdio.h>  int main(void) {     int n = 590;     double a[n][n];     double b[n][n];     double c[n][n];     printf("done"); }
  • set n value <= 590:
    runs without errors, or without output.
  • set n value > 590:
    • runs flawlessy output line removed.
    • compile , run output: segmentation fault

what's reason this? can explain?

you try allocate more memory it's available on stack causes stack overflow. better allocate huge arrays dynamically using malloc, calloc or realloc. don't forget free memory calling free when finish :)

these questions too:
c/c++ maximum stack size of program
segmentation fault on creating array in c
segmentation fault when using variable initiate array


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