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/* For a long time (from Valgrind 1.0 to 1.9.6, AFAICT) when realloc() was
called and made a block smaller, or didn't change its size, the
ExeContext of the block was not updated; therefore any errors that
referred to it would state that it was allocated not by the realloc(),
but by the previous malloc() or whatever. While this is true in one
sense, it is misleading and not what you'd expect. This test
demonstrates this -- 'x' and 'y' are unchanged and shrunk, and their
ExeContexts should be updated upon their realloc(). I hope that's clear.
*/
#include <stdlib.h>
int main(void)
{
int* x = malloc(5);
int* y = malloc(10);
int* z = malloc(2);
int a, b, c;
x = realloc(x, 5); // same size
y = realloc(y, 5); // make smaller
z = realloc(z, 5); // make bigger
a = (x[5] == 0xdeadbeef ? 1 : 0);
b = (y[5] == 0xdeadbeef ? 1 : 0);
c = (z[5] == 0xdeadbeef ? 1 : 0);
return a + b + c;
}
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