From: Andrzej Hunt <ajrhunt@xxxxxxxxxx> 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 <ajrhunt@xxxxxxxxxx> --- Update 'make fuzz-all' docs to reflect modern clang This version of the patch fixes the commit message as per Junio's feedback. Thank you! Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-889%2Fahunt%2Ffuzz-docs-v3 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-889/ahunt/fuzz-docs-v3 Pull-Request: https://github.com/gitgitgadget/git/pull/889 Range-diff vs v2: 1: f5b5a11966ca ! 1: bc0d8b615410 Update 'make fuzz-all' docs to reflect modern clang @@ Metadata Author: Andrzej Hunt <ajrhunt@xxxxxxxxxx> ## Commit message ## - Update 'make fuzz-all' docs to reflect modern clang + 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. + 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 ensure that all the required - instrumentation is added when compiling git [1], and remove + 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. + 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: + (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 Makefile | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/Makefile b/Makefile index dfb0f1000fa3..f3dc2178324e 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) base-commit: be7935ed8bff19f481b033d0d242c5d5f239ed50 -- gitgitgadget
