The current value ``` LIBFUZZER = /home/nickm/build/libfuzz/libFuzzer.a ``` isn't portable enough IMO. BTW if I configure the sources (with clang 3.9.1): ``` CC="clang" ./configure --config-cache --enable-expensive-hardening --enable-libfuzzer ``` then I run during make into ``` $ make make all-am make[1]: Entering directory '/home/tfoerste/devel/tor' AR src/ext/keccak-tiny/libkeccak-tiny.a AR src/trunnel/libor-trunnel.a CC src/ext/trunnel/src_trunnel_libor_trunnel_testing_a-trunnel.o clang-3.9: error: unsupported argument 'trace-pc-guard' to option 'fsanitize-coverage=' clang-3.9: error: unsupported argument 'trace-div' to option 'fsanitize-coverage=' make[1]: *** [Makefile:7704: src/ext/trunnel/src_trunnel_libor_trunnel_testing_a-trunnel.o] Error 1 make[1]: Leaving directory '/home/tfoerste/devel/tor' make: *** [Makefile:3044: all] Error 2 ``` at a stable (hardened) Gentoo Linux.