If built as part of the main llvm build, via ENABLE_LLVM_PROJECTS=compiler-rt, the code gets built with more warning options than if built standalone. Some of these trigger warnings like: warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]
Compiler-RT ================================ This directory and its subdirectories contain source code for the compiler support routines. Compiler-RT is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. ================================