llvm:clang-objc-fuzzer: Segv on unknown address in clang::Expr::EvaluateKnownConstInt

Detailed Report: https://oss-fuzz.com/testcase?key=5105673205710848

Project: llvm
Fuzzing Engine: libFuzzer
Fuzz Target: clang-objc-fuzzer
Job Type: libfuzzer_msan_llvm
Platform Id: linux

Crash Type: Segv on unknown address
Crash Address:
Crash State:
clang::Expr::EvaluateKnownConstInt
clang::FieldDecl::getBitWidthValue
clang::FieldDecl::isZeroLengthBitField

Sanitizer: memory (MSAN)

Regressed: https://oss-fuzz.com/revisions?job=libfuzzer_msan_llvm&range=201911200438:201911230451

Reproducer Testcase: https://oss-fuzz.com/download?testcase_id=5105673205710848

Issue filed automatically.

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