developers aim to reduce memory footprint and increase compilation speed compared to competing compilers, such as GCC. In October 2007, they report that Clang compiled the Carbon libraries more than twice as fast as GCC, while using about one-sixth GCC's memory and disk space. By 2011, Clang seems to retain this advantage in compiler performance. As of mid-2014, Clang still consistently compiles faster than GCC in a mixed compile time and program performance benchmark. However, by 2019, Clang is significantly slower at compiling the Linux Kernel than GCC while remaining slightly faster at compiling LLVM. While Clang has historically been faster than GCC at compiling, the output quality has lagged behind. As of 2014, performance of Clang-compiled programs lagged behind performance of the GCC-compiled program, sometimes by large factors (up to 5.5x), replicating earlier reports of slower performance. Both compilers have evolved to increase their performance since then, with the gap narrowing: Comparisons in November 2016 between GCC 4.8.2 versus clang 3.4, on a large harness of test files shows that GCC outperforms clang by approximately 17% on well-optimized source code. Test results are code-specific, and unoptimized C source code can reverse such differences. The two compilers thus seem broadly comparable. Comparisons in 2019 on Intel Ice Lake has shown that programs generated by Clang 10 has achieved 96% of the performance of GCC 10 over 41 different benchmarks (while winning 22 and losing 19 out of them). Interface libclang provides a C interface, providing a relatively small API. Exposed functionality includes: parsing source code into an AST, loading ASTs, traversing the AST, associating source locations with elements within the AST. Status history This table presents only significant steps and releases in Clang history. See also AMD Optimizing C/C++ Compiler LLDB Portable C Compiler References External links Apple Inc. software C (programming language) compilers C++ compilers Free compilers and interpreters Software using the NCSA license Software using the Apache license Static program analysis tools 2007 software