similar to: Building LLVM's fuzzers

George Karpenkov <ekarpenkov at apple.com> writes: > OK so with Kuba’s help I’ve found the error: with optimization, dead > stripping of produced libraries is enabled, > which removes coverage instrumentation. > > However, this has nothing to do with the move to compiler-rt, so I’m > quite skeptical on whether it has worked > beforehand. > > A trivial fix is to do:

George Karpenkov <ekarpenkov at apple.com> writes: > Should -DCMAKE_CXX_COMPILER be also specified? CMake is smart enough to infer that from C_COMPILER: % grep CMAKE_CXX_COMPILER CMakeCache.txt CMAKE_CXX_COMPILER:FILEPATH=/Users/bogner/llvm-lkgc/bin/clang++ >> On Aug 24, 2017, at 11:29 AM, Justin Bogner <mail at justinbogner.com> wrote: >> >> (kcc, george:

> On Aug 24, 2017, at 2:55 PM, Kostya Serebryany <kcc at google.com> wrote: > > Interesting. > This is a relatively new addition (fsanitize-coverage=pc-tables, which is now a part of -fsanitize=fuzzer). > The tests worked (did they? On Mac?) so I thought everything is ok. For tests we never compile the tested target with -O3 (and that wouldn’t be sufficient), and for

I think the simplest fix is something like this: diff --git a/lib/Transforms/Instrumentation/SanitizerCoverage.cpp b/lib/Transforms/Instrumentation/SanitizerCoverage.cpp index c6f0d17f8fe..e81957ab80a 100644 --- a/lib/Transforms/Instrumentation/SanitizerCoverage.cpp +++ b/lib/Transforms/Instrumentation/SanitizerCoverage.cpp @@ -256,6 +256,7 @@ SanitizerCoverageModule::CreateSecStartEnd(Module

On Thu, Aug 24, 2017 at 3:21 PM, Kostya Serebryany via llvm-dev < llvm-dev at lists.llvm.org> wrote: > > > On Thu, Aug 24, 2017 at 3:20 PM, Justin Bogner <mail at justinbogner.com> > wrote: > >> I think the simplest fix is something like this: >> >> diff --git a/lib/Transforms/Instrumentation/SanitizerCoverage.cpp >>

On Thu, Aug 24, 2017 at 3:38 PM, Kostya Serebryany <kcc at google.com> wrote: > > > On Thu, Aug 24, 2017 at 3:35 PM, Peter Collingbourne <peter at pcc.me.uk> > wrote: > >> On Thu, Aug 24, 2017 at 3:21 PM, Kostya Serebryany via llvm-dev < >> llvm-dev at lists.llvm.org> wrote: >> >>> >>> >>> On Thu, Aug 24, 2017 at 3:20

On Thu, Aug 24, 2017 at 6:30 PM, Justin Bogner <mail at justinbogner.com> wrote: > Peter Collingbourne <peter at pcc.me.uk> writes: > > On Thu, Aug 24, 2017 at 3:38 PM, Kostya Serebryany <kcc at google.com> > wrote: > > > >> > >> > >> On Thu, Aug 24, 2017 at 3:35 PM, Peter Collingbourne <peter at pcc.me.uk> > >> wrote:

Kostya Serebryany <kcc at google.com> writes: > Justin, > Calling appendToUsed has horrible complexity and if we call it in > every function clang consumes tons of memory (6Gb when compiling one > of the clang's source files). This killed my machine today :) > > The solution is to call appendToUsed once per module, instead of once > per function. Oh right,

Hello List, I'm currently writing my own little optimization pass (on LLVM 6.0) and considered it a neat idea to fuzz it using llvm-opt-fuzzer, which in theory should be a ready-made tool for such jobs as far as I can tell, potentially helping me to find UB and Address issues in my pass. So I went ahead and followed the instructions in the build manual [1] to build LLVM's llvm-opt-fuzzer

I decided to try out the fuzzer library and clang-fuzzer, but it doesn't seem to build for me. From the cmake files, I was pretty sure all I need to do is set -DLLVM_USE_SANITIZE_COVERAGE=ON, but with this I get a number of link errors for "lib/Fuzzer/test/LLVMFuzzer-CounterTest", for example: lib/libLLVMFuzzer.a(FuzzerLoop.cpp.o): In function `SetDeathCallback':

Hi, This started as an off hand comment in [1] but this appears to be a real issue so I'm moving the discussion to the mailing list. In r270942 the time taken to run LibFuzzer's test became noticeably longer. I am building on * Arch Linux (4.5.4-1-ARCH #1 SMP PREEMPT Wed May 11 22:21:28 CEST 2016 x86_64 GNU/Linux) * I am building libFuzzer and running its tests like so ```

Reproduced, should be easy to fix. Will do it. And thanks for noticing, on my machine this fails very fast and the test passes because it sees everything it wants to see. --kcc On Fri, May 27, 2016 at 6:18 PM, Dan Liew <dan at su-root.co.uk> wrote: > Hi, > > This started as an off hand comment in [1] but this appears to be a > real issue so I'm moving the discussion to the

On Tue, Jul 11, 2017 at 7:02 PM, George Karpenkov <ekarpenkov at apple.com> wrote: > I’ve submitted a WIP PR: https://reviews.llvm.org/D35288 > Thanks for working in this! One question: will it make sense to *copy* the code to the new location, work on it, then delete the code from the old location, instead of doing a move in a single commit? I don't expect any dramatic changes

r247321 refactors the code so that it should build on Mac. I haven't actually tested it on Mac -- so please help me and send follow up patches if needed. check-fuzzer will still fail because some of the libFuzzer tests require dfsan. I'd use some help from someone with a Mac to modify lib/Fuzzer/test/CMakeLists.txt so that it does not run dfsan-dependent tests on Mac. Thanks, --kcc On

I have a project I want to do based on Libfuzzer. Is there a separate list for it or should I bring up any ideas for it here? What I have in mind is to fuzz Postgres. Trying to fuzz the SQL interpreter in general is not very productive because traditional fuzzers try to execute the entire program repeatedly and it has a fairly high startup and shutdown cost. Also the instrumentation-guided

On Wed, Jul 12, 2017 at 11:30 AM, George Karpenkov <ekarpenkov at apple.com> wrote: > > On Jul 12, 2017, at 11:01 AM, Kostya Serebryany <kcc at google.com> wrote: > One question: will it make sense to *copy* the code to the new location, > work on it, then delete the code from the old location, > instead of doing a move in a single commit? > I don't expect any

On Wed, Jul 12, 2017 at 11:54 AM, George Karpenkov <ekarpenkov at apple.com> wrote: > > On Jul 12, 2017, at 11:34 AM, Kostya Serebryany <kcc at google.com> wrote: > > > > On Wed, Jul 12, 2017 at 11:30 AM, George Karpenkov <ekarpenkov at apple.com> > wrote: > >> >> On Jul 12, 2017, at 11:01 AM, Kostya Serebryany <kcc at google.com> wrote:

+ Chandler, Danny, We are considering to move the libFuzzer code from llvm to compiler-rt, and that implies a license change. Will it be sufficient to do the following? * e-mail to all contributors (a short list, below) asking for their consent * remove any code for which we did not get consent in, say, 1 week. (BTW, this list is actually much shorter, I recognize many of these as belonging

I am working of using libfuzzer and asan to test out a third-party library. As demonstrated in the tutorial, I wrote a fuzz target to fuzz a specific function in the library. The fuzz target is then linked to the library and compiles clean and I do see some tests generated by the fuzzer. However, I have some questions regarding the "right" way to go about doing this. I have doubts that

Hi Mitch, Thank you for the response. 1. You don't need to build the library with `-fsanitize-coverage=...`, using `-fsanitize=fuzzer-no-link,address` should be sufficient. - Acknowledged 2. (although you can actually build object files/shared libraries with -fsanitize=fuzzer, and the libFuzzer main won't be linked, if this makes your build process easier). - with just the *fuzzer