The LLVM Project is a collection of modular and reusable compiler and toolchain technologies. Despite its name, LLVM has little to do with traditional virtual machines. The name "LLVM" itself is not an acronym; it is the full name of the project. LLVM began as a research project at the University of Illinois , with the goal of providing a modern, SSA-based compilation strategy capable of supporting both static and dynamic compilation of arbitrary programming languages. Since then, LLVM has grown to be an umbrella project consisting of a number of subprojects, many of which are being used in production by a wide variety of commercial and open source projects as well as being widely used in academic research . Code in the LLVM project is licensed under the "Apache 2.0 License with LLVM exceptions" The primary sub-projects of LLVM are: The LLVM Core libraries provide a modern source- and target-independent optimizer , along with code generation support for many popular CPUs (as well as some less common ones!) These libraries are built around a well specified code representation known as the LLVM intermediate representation ("LLVM IR"). The LLVM Core libraries are well documented , and it is particularly easy to invent your own language (or port an existing compiler) to use LLVM as an optimizer and code generator . The LLVM Core libraries provide a modern source- and target-independent optimizer , along with code generation support for many popular CPUs (as well as some less common ones!) These libraries are built around a well specified code representation known as the LLVM intermediate representation ("LLVM IR"). The LLVM Core libraries are well documented , and it is particularly easy to invent your own language (or port an existing compiler) to use LLVM as an optimizer and code generator . Clang is an "LLVM native" C/C++/Objective-C compiler, which aims to deliver amazingly fast compiles, extremely useful error and warning messages and to provide a platform for building great source level tools. The Clang Static Analyzer and clang-tidy are tools that automatically find bugs in your code, and are great examples of the sort of tools that can be built using the Clang frontend as a library to parse C/C++ code. Clang is an "LLVM native" C/C++/Objective-C compiler, which aims to deliver amazingly fast compiles, extremely useful error and warning messages and to provide a platform for building great source level tools. The Clang Static Analyzer and clang-tidy are tools that automatically find bugs in your code, and are great examples of the sort of tools that can be built using the Clang frontend as a library to parse C/C++ code. Flang is a modern Fortran compiler with an associated runtime, which aims to generate high-performance code, and support Fortran 2023 and all official Fortran standards going back to Fortran 77, including a number of widely-used extensions . Flang supports OpenMP for both CPUs and GPUs. Flang is a modern Fortran compiler with an associated runtime, which aims to generate high-performance code, and support Fortran 2023 and all official Fortran standards going back to Fortran 77, including a number of widely-used extensions . Flang supports OpenMP for both CPUs and GPUs. The LLDB project builds on libraries provided by LLVM and Clang to provide a great native debugger. It uses the Clang ASTs and expression parser, LLVM JIT, LLVM disassembler, etc so that it provides an experience that "just works". It is also blazing fast and much more memory efficient than GDB at loading symbols. The LLDB project builds on libraries provided by LLVM and Clang to provide a great native debugger. It uses the Clang ASTs and expression parser, LLVM JIT, LLVM disassembler, etc so that it provides an experience that "just works". It is also blazing fast and much more memory efficient than GDB at loading symbols. The libc++ and libc++ ABI projects provide a standard conformant and high-performance implementation of the C++ Standard Library, including full support for C++11 and C++14. The libc++ and libc++ ABI projects provide a standard conformant and high-performance implementation of the C++ Standard Library, including full support for C++11 and C++14. The libc project provides a high-performance, standards-conformant implementation of the C Standard Library, fully integrated with LLVM. It delivers optimized performance and comprehensive support for modern C standards, ensuring a reliable and efficient foundation for C applications. The libc project provides a high-performance, standards-conformant implementation of the C Standard Library, fully integrated with LLVM. It delivers optimized performance and comprehensive support for modern C standards, ensuring a reliable and efficient foundation for C applications. The compiler-rt project provides highly tuned implementations of the low-level code generator support routines like " __fixunsdfdi " and other calls generated when a target doesn't have a short sequence of native instructions to implement a core IR operation. It also provides implementations of run-time libraries for dynamic testing tools such as AddressSanitizer , ThreadSanitizer , MemorySanitizer , and DataFlowSanitizer . The compiler-rt project provides highly tuned implementations of the low-level code generator support routines like " __fixunsdfdi " and other calls generated when a target doesn't have a short sequence of native instructions to implement a core IR operation. It also provides implementations of run-time libraries for dynamic testing tools such as AddressSanitizer , ThreadSanitizer , MemorySanitizer , and DataFlowSanitizer . The MLIR subproject is a novel approach to building reusable and extensible compiler infrastructure. MLIR aims to address software fragmentation, improve compilation for heterogeneous hardware, significantly reduce the cost of building domain specific compilers, and aid in connecting existing compilers together. The MLIR subproject is a novel approach to building reusable and extensible compiler infrastructure. MLIR aims to address software fragmentation, improve compilation for heterogeneous hardware, significantly reduce the cost of building domain specific compilers, and aid in connecting existing compilers together. The OpenMP subproject provides an OpenMP runtime for use with the OpenMP implementation in Clang and Flang. The OpenMP subproject provides an OpenMP runtime for use with the OpenMP implementation in Clang and Flang. The polly project implements a suite of cache-locality optimizations as well as auto-parallelism and vectorization using a polyhedral model. The polly project implements a suite of cache-locality optimizations as well as auto-parallelism and vectorization using a polyhedral model. The libclc project aims to implement the OpenCL standard library. The libclc project aims to implement the OpenCL standard library. The klee project implements a "symbolic virtual machine" which uses a theorem prover to try to evaluate all dynamic paths through a program in an effort to find bugs and to prove properties of functions. A major feature of klee is that it can produce a testcase in the event that it detects a bug. The klee project implements a "symbolic virtual machine" which uses a theorem prover to try to evaluate all dynamic paths through a program in an effort to find bugs and to prove properties of functions. A major feature of klee is that it can produce a testcase in the event that it detects a bug. The LLD project is a new linker. That is a drop-in replacement for system linkers and runs much faster. The LLD project is a new linker. That is a drop-in replacement for system linkers and runs much faster. The BOLT project is a post-link optimizer. It achieves the improvements by optimizing application's code layout based on execution profile gathered by sampling profiler. The BOLT project is a post-link optimizer. It achieves the improvements by optimizing application's code layout based on execution profile gathered by sampling profiler. In addition to official subprojects of LLVM, there are a broad variety of other projects that use components of LLVM for various tasks . Through these external projects you can use LLVM to compile Ruby, Python, Haskell, Rust, D, PHP, Pure, Lua, Julia, and a number of other languages. A major strength of LLVM is its versatility, flexibility, and reusability, which is why it is being used for such a wide variety of different tasks: everything from doing light-weight JIT compiles of embedded languages like Lua to compiling Fortran code for massive super computers. As much as everything else, LLVM has a broad and friendly community of people who are interested in building great low-level tools. If you are interested in getting involved , a good first place is to skim the LLVM Blog and join LLVM Discourse . For information on how to send in a patch, get commit access, and copyright and license topics, please see the LLVM Developer Policy . 8 September 2026 : LLVM 23.1.1 is now available for download ! LLVM is publicly available under an open source License . Also, you might want to check out the new features in Git that will appear in the next LLVM release. If you want them early, download LLVM through anonymous Git. October 26-28 2026 US LLVM LLVM has been awarded the 2012 ACM Software System Award ! This award is given by ACM to one software system worldwide every year. LLVM is in highly distinguished company ! Click on any of the individual recipients' names on that page for the detailed citation describing the award. LLVM Release Schedule: 23.1.x Tue Jul 14th, 2026: release/23.x branch Fri Jul 17th, 2026: 23.1.0-rc1 was released Tue Jul 28th, 2026: 23.1.0-rc2 was released Tue Aug 12th, 2026: 23.1.0-rc3 was released Tue Aug 25th, 2026: 23.1.0 was released Tue Sep 8th, 2026: 23.1.1 was released Tue Sep 22nd, 2026: 23.1.2 Tue Oct 6th, 2026: 23.1.3 Tue Oct 20th, 2026: 23.1.4 Tue Nov 3rd, 2026: 23.1.5 Tue Nov 17th, 2026: 23.1.6 Tue Dec 1st, 2026: 23.1.7 Tue Dec 15th, 2026: 23.1.8 Tue Dec 29th, 2026: 23.1.9 (if necessary) Tue Jul 14th, 2026: release/23.x branch Fri Jul 17th, 2026: 23.1.0-rc1 was released

Tue Jul 28th, 2026: 23.1.0-rc2 was released Tue Aug 12th, 2026: 23.1.0-rc3 was released Tue Aug 25th, 2026: 23.1.0 was released Tue Sep 8th, 2026: 23.1.1 was released Tue Sep 22nd, 2026: 23.1.2 Tue Oct 6th, 2026: 23.1.3 Tue Oct 20th, 2026: 23.1.4 Tue Nov 3rd, 2026: 23.1.5 Tue Nov 17th, 2026: 23.1.6 Tue Dec 1st, 2026: 23.1.7 Tue Dec 15th, 2026: 23.1.8 Tue Dec 29th, 2026: 23.1.9 (if necessary) October 26-28, 2026 Proceedings from past meetings: April 13-15, 2026 October 27-29, 2025 April 14-16, 2025 October 22-24, 2024 April 10-11, 2024 October 9-11, 2023 May 10-11, 2023 November 8-9, 2022 May 10-11, 2022 November 16-19, 2021 October 6-8, 2020 October 22-23, 2019 April 8-9, 2019 October 17-18, 2018 April 16-17, 2018 October 18-19, 2017 March 27-28, 2017 November 3-4, 2016 March 17-18, 2016 October 29-30, 2015 April 13-14, 2015 October 28-29, 2014 April 7-8, 2014 April 29-30, 2013 November 7-8, 2012 November 18, 2011