From 68b5c3aa48980bcbe2ec2c1336b615baf1935613 Mon Sep 17 00:00:00 2001 From: Andrzej Hunt Date: Mon, 8 Mar 2021 17:14:42 +0000 Subject: [PATCH] Makefile: update 'make fuzz-all' docs to reflect modern clang Clang no longer produces a libFuzzer.a. Instead, you can include libFuzzer by using -fsanitize=fuzzer. Therefore we should use that in the example command for building fuzzers. We also add -fsanitize=fuzzer-no-link to the CFLAGS to ensure that all the required instrumentation is added when compiling git [1], and remove -fsanitize-coverage=trace-pc-guard as it is deprecated. I happen to have tested with LLVM 11 - however -fsanitize=fuzzer appears to work in a wide range of reasonably modern clangs. (On my system: what used to be libFuzzer.a now lives under the following path, which is tricky albeit not impossible for a novice such as myself to find: /usr/lib64/clang/11.0.0/lib/linux/libclang_rt.fuzzer-x86_64.a ) [1] https://releases.llvm.org/11.0.0/docs/LibFuzzer.html#fuzzer-usage Signed-off-by: Andrzej Hunt Signed-off-by: Junio C Hamano --- Makefile | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/Makefile b/Makefile index dfb0f1000f..f3dc217832 100644 --- a/Makefile +++ b/Makefile @@ -3299,11 +3299,11 @@ cover_db_html: cover_db # are not necessarily appropriate for general builds, and that vary greatly # depending on the compiler version used. # -# An example command to build against libFuzzer from LLVM 4.0.0: +# An example command to build against libFuzzer from LLVM 11.0.0: # # make CC=clang CXX=clang++ \ -# CFLAGS="-fsanitize-coverage=trace-pc-guard -fsanitize=address" \ -# LIB_FUZZING_ENGINE=/usr/lib/llvm-4.0/lib/libFuzzer.a \ +# CFLAGS="-fsanitize=fuzzer-no-link,address" \ +# LIB_FUZZING_ENGINE="-fsanitize=fuzzer" \ # fuzz-all # FUZZ_CXXFLAGS ?= $(CFLAGS)