testub.cc

#include <cstdint>
#include <stdio.h>
#include <emscripten.h>

using namespace std;

struct source_location {
	const char *file_name;
	union {
		unsigned long reported;
		struct {
			uint32_t line;
			uint32_t column;
		};
	};
};

struct type_descriptor {
	uint16_t type_kind;
	uint16_t type_info;
	char type_name[1];
};


struct overflow_data {
	struct source_location location;
	struct type_descriptor *type;
};


extern "C" {
void EMSCRIPTEN_KEEPALIVE __ubsan_handle_add_overflow(struct overflow_data *data,
  unsigned long lhs,
  unsigned long rhs)
{

  printf("Overflow happened %lu + %lu @%s\n", lhs, rhs, data->location.file_name);
}
}


int main(int argc, char **argv) {
  int k = 0x7fffffff;
  k += argc;
  return 0;
}