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/*
* Copyright 2018 The Emscripten Authors. All rights reserved.
* Emscripten is available under two separate licenses, the MIT license and the
* University of Illinois/NCSA Open Source License. Both these licenses can be
* found in the LICENSE file.
*/
#include <stdlib.h>
#include <setjmp.h>
#include <stdio.h>
#include <assert.h>
#include <emscripten/stack.h>
#define abs(x) ((x) < 0 ? (-x) : (x))
// A minor stack change is ignorable (e.g., printf)
#define MINOR 100
// A major stack change must not happen
#define MAJOR 1000
jmp_buf jb;
__attribute__((noinline)) void bar()
{
printf("before longjmp: %ld\n", emscripten_stack_get_current());
longjmp(jb, 1);
}
volatile void* temp;
__attribute__((noinline)) void foo()
{
temp = alloca(MAJOR);
printf("major allocation at: %d\n", (int)temp);
assert(abs(emscripten_stack_get_current() - (int)temp) >= MAJOR);
bar();
}
int main()
{
int before = emscripten_stack_get_current();
printf("before setjmp: %d\n", before);
if (!setjmp(jb)) {
foo();
return 0;
} else {
int after = emscripten_stack_get_current();
printf("before setjmp: %d\n", after);
assert(abs(after - before) < MINOR); // stack has been unwound (but may have minor printf changes
printf("ok.\n");
return 1;
}
}
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