[PATCH] D48891: [libFuzzer] Make -fsanitize=memory,fuzzer work.

[Max Moroz via Phabricator via llvm-commits]

Dor1s added a comment.

Hey Matt, this new test seems to be failing for me locally. I've run `ninja check-msan`, but it doesn't help. I assume that the problem is on my side, do you have any clue what I can be missing?

The failure is that it doesn't print `BINGO`, as it seems to be crashing before that:

  #4523	REDUCE cov: 6 ft: 6 corp: 5/9b lim: 6 exec/s: 0 rss: 38Mb L: 3/3 MS: 3 CopyPart-EraseBytes-InsertByte-
  ==103360==WARNING: MemorySanitizer: use-of-uninitialized-value
      #0 0x53ca2b in std::__1::basic_ostream<char, std::__1::char_traits<char> >& std::__1::__put_character_sequence<char, std::__1::char_traits<char> >(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, unsigned long) <...>llvm/build/bin/../include/c++/v1/ostream:722:13
      #1 0x53c4c1 in LLVMFuzzerTestOneInput <...>llvm/llvm/projects/compiler-rt/test/fuzzer/SimpleTest.cpp:21:19
      #2 0x4528ac in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) <...>llvm/llvm/projects/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:531
      #3 0x459cd6 in fuzzer::Fuzzer::RunOne(unsigned char const*, unsigned long, bool, fuzzer::InputInfo*, bool*) <...>llvm/llvm/projects/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:452
      #4 0x459cd6 in fuzzer::Fuzzer::MutateAndTestOne() <...>llvm/llvm/projects/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:664
      #5 0x45d83f in fuzzer::Fuzzer::Loop(std::__Fuzzer::vector<std::__Fuzzer::basic_string<char, std::__Fuzzer::char_traits<char>, std::__Fuzzer::allocator<char> >, fuzzer::fuzzer_allocator<std::__Fuzzer::basic_string<char, std::__Fuzzer::char_traits<char>, std::__Fuzzer::allocator<char> > > > const&) <...>llvm/llvm/projects/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:794
      #6 0x44e233 in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) <...>llvm/llvm/projects/compiler-rt/lib/fuzzer/FuzzerDriver.cpp:760
      #7 0x421272 in main <...>llvm/llvm/projects/compiler-rt/lib/fuzzer/FuzzerMain.cpp:20
      #8 0x7f9a300502b0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202b0)
      #9 0x4212a9 in _start (<...>llvm/build/projects/compiler-rt/test/fuzzer/Output/msan.test.tmp+0x4212a9)
  
  SUMMARY: MemorySanitizer: use-of-uninitialized-value <...>llvm/build/bin/../include/c++/v1/ostream:722:13 in std::__1::basic_ostream<char, std::__1::char_traits<char> >& std::__1::__put_character_sequence<char, std::__1::char_traits<char> >(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, char const*, unsigned long)
  Exiting
  MS: 1 ChangeBit-; base unit: ba5baccb9bbf5a3e04d647914437de87a1fae521
  0x48,0x69,0x21,
  Hi!
  artifact_prefix='./'; Test unit written to ./crash-c0a0ad26a634840c67a210fefdda76577b03a111
  Base64: SGkh


Repository:
  rCRT Compiler Runtime

https://reviews.llvm.org/D48891