Question

float **tree0;

tree0 = (float**)malloc(255 * sizeof(float*));

for( i = 0; i < 255; i++) 
    tree0[i] = (float*)malloc(M * sizeof(float));
for(i = 0; i < 255; i++)
    for( k = 0; k < M; k++)
        tree0[i][k] = 2;

Should I just free it like this

free(tree0);

I am heap corruption errors somewhere and thought this might be the problem…

Answer 1

You need to call free() as many times as you called malloc() and on the same addresses which was returned by malloc(). So, You just do it the way you allocated it:

for( i = 0; i < 255; i++) 
    free(tree0[i])

free(tree0);