How REX Cut Build Time With Private Precompiled Headers

Thu, 04 Jun 2026 00:00:00 +0000

Compiler projects spend a lot of time compiling themselves.

That sounds obvious, but it becomes painfully concrete in REX. The project is a source-to-source compiler built around Sage IR, generated ROSETTA headers, a Clang frontend, a Flang frontend, OpenMP parsing, unparsing, midend analysis, and a large test suite. Many translation units include the same heavy internal headers. Every clean build asks the compiler to parse those headers again and again.

Cmake on ./Code

How REX Cut Build Time With Private Precompiled Headers