1  // Copyright (c) 2019-2021 The Bitcoin Core developers
 2  // Distributed under the MIT software license, see the accompanying
 3  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 4  
 5  #include <boost/test/unit_test.hpp>
 6  
 7  BOOST_AUTO_TEST_SUITE(compilerbug_tests)
 8  
 9  #if defined(__GNUC__)
10  // This block will also be built under clang, which is fine (as it supports noinline)
11  void __attribute__ ((noinline)) set_one(unsigned char* ptr)
12  {
13      *ptr = 1;
14  }
15  
16  int __attribute__ ((noinline)) check_zero(unsigned char const* in, unsigned int len)
17  {
18      for (unsigned int i = 0; i < len; ++i) {
19          if (in[i] != 0) return 0;
20      }
21      return 1;
22  }
23  
24  void set_one_on_stack() {
25      unsigned char buf[1];
26      set_one(buf);
27  }
28  
29  BOOST_AUTO_TEST_CASE(gccbug_90348) {
30      // Test for GCC bug 90348. See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90348
31      for (int i = 0; i <= 4; ++i) {
32          unsigned char in[4];
33          for (int j = 0; j < i; ++j) {
34              in[j] = 0;
35              set_one_on_stack(); // Apparently modifies in[0]
36          }
37          BOOST_CHECK(check_zero(in, i));
38      }
39  }
40  #endif
41  
42  BOOST_AUTO_TEST_SUITE_END()