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// RUN: %clang_safestack -fno-stack-protector -D_FORTIFY_SOURCE=0 -g %s -o %t.nossp
// RUN: %run %t.nossp 2>&1 | FileCheck --check-prefix=NOSSP %s
// RUN: %clang_safestack -fstack-protector-all -D_FORTIFY_SOURCE=0 -g %s -o %t.ssp
// RUN: not --crash %run %t.ssp 2>&1 | FileCheck -check-prefix=SSP %s
// Test stack canaries on the unsafe stack.
// REQUIRES: stable-runtime
#include <assert.h>
#include <stdio.h>
#include <string.h>
__attribute__((noinline)) void f(unsigned *y) {
char x;
char *volatile p = &x;
char *volatile q = (char *)y;
assert(p < q);
assert(q - p < 1024); // sanity
// This has technically undefined behavior, but we know the actual layout of
// the unsafe stack and this should not touch anything important.
memset(&x, 0xab, q - p + sizeof(*y));
}
int main(int argc, char **argv)
{
unsigned y;
// NOSSP: main 1
// SSP: main 1
fprintf(stderr, "main 1\n");
f(&y);
// NOSSP: main 2
// SSP-NOT: main 2
fprintf(stderr, "main 2\n");
return 0;
}
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