llvm toolset

How to debug where a function returns using LLDB from the command line

How to debug where a function returns using LLDB from the command line

I often find myself in a situation when I want to know where a function returns. There’s no need to know the return value, as this may be the same for multiple code paths (e.g., nullptr if something went wrong). It is embarrassing, but I sometimes have put fprintf(stderr, "T1"); in my code just to follow which path the execution took. Needless to say, this behavior requires manual editing and recompilation and should be avoided if possible.

Here’s a way to elegantly debug where a function returns using lldb from the command line.

Continue reading “How to debug where a function returns using LLDB from the command line”

Share
Introduction to using libFuzzer with llvm-toolset

Introduction to using libFuzzer with llvm-toolset

“Fuzzing” an application is a great way to find bugs that may be missed by other testing methods. Fuzzers test programs by generating random string inputs and feeding them into an application. Any program that accepts arbitrary inputs from its users is a good candidate for fuzzing. This includes compilers, interpreters, web applications, JSON or YAML parsers, and many more types of programs.

libFuzzer is a library to assist with the fuzzing of applications and libraries. It is integrated into the Clang C compiler and can be enabled for your application with the addition of a compile flag and by adding a fuzzing target to your code. libFuzzer has been used successfully to find bugs in many programs, and in this article, I will show how you can integrate libFuzzer into your own applications.

Continue reading “Introduction to using libFuzzer with llvm-toolset”

Share
How to install GCC 8 and Clang/LLVM 6 on Red Hat Enterprise Linux 7

How to install GCC 8 and Clang/LLVM 6 on Red Hat Enterprise Linux 7

There has been a lot of work to improve C/C++ compilers in recent years. A number of articles have been posted by Red Hat engineers working on the compilers themselves covering usability improvements, features to detect possible bugs, and security issues in your code.

Red Hat Enterprise Linux 8 Beta ships with GCC 8 as the default compiler. This article shows you how to install GCC 8 as well as Clang/LLVM 6 on Red Hat Enterprise Linux 7. You’ll be able to use the same updated (and supported) compilers from Red Hat on both RHEL 7 and 8.

If you want your default gcc to always be GCC 8, or you want clang to always be in your path, this article shows how to permanently enable a software collection by adding it to the profile (dot files) for your user account. A number of common questions about software collections are also answered.

Continue reading “How to install GCC 8 and Clang/LLVM 6 on Red Hat Enterprise Linux 7”

Share