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//===---------------------- backtrace_test.cpp ----------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: no-exceptions
#include <assert.h>
#include <stddef.h>
#include <unwind.h>
extern "C" _Unwind_Reason_Code
trace_function(struct _Unwind_Context*, void* ntraced) {
(*reinterpret_cast<size_t*>(ntraced))++;
// We should never have a call stack this deep...
assert(*reinterpret_cast<size_t*>(ntraced) < 20);
return _URC_NO_REASON;
}
__attribute__ ((__noinline__))
void call3_throw(size_t* ntraced) {
try {
_Unwind_Backtrace(trace_function, ntraced);
} catch (...) {
assert(false);
}
}
__attribute__ ((__noinline__, __disable_tail_calls__))
void call3_nothrow(size_t* ntraced) {
_Unwind_Backtrace(trace_function, ntraced);
}
__attribute__ ((__noinline__, __disable_tail_calls__))
void call2(size_t* ntraced, bool do_throw) {
if (do_throw) {
call3_throw(ntraced);
} else {
call3_nothrow(ntraced);
}
}
__attribute__ ((__noinline__, __disable_tail_calls__))
void call1(size_t* ntraced, bool do_throw) {
call2(ntraced, do_throw);
}
int main() {
size_t throw_ntraced = 0;
size_t nothrow_ntraced = 0;
call1(¬hrow_ntraced, false);
try {
call1(&throw_ntraced, true);
} catch (...) {
assert(false);
}
// Different platforms (and different runtimes) will unwind a different number
// of times, so we can't make any better assumptions than this.
assert(nothrow_ntraced > 1);
assert(throw_ntraced == nothrow_ntraced); // Make sure we unwind through catch
return 0;
}
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