6f4add3480
compiler-rt/lib/fuzzer/tests build was failing on armv7, with undefined references to unwinder symbols, such as __aeabi_unwind_cpp_pr0. This occurs because the test is built with `-nostdlib++` but `libunwind` is not explicitly linked to the final test executable. This patch resolves the issue by adding CMake logic to explicitly link the required unwinder to the fuzzer tests, inspired by the same solution used to fix Scudo build failures by https://reviews.llvm.org/D142888.
See http://llvm.org/docs/LibFuzzer.html