Serge Guelton

compiler engineer

Compiler engineer, wood chopper, bread baker and other stuff in *er

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A compiler option, a hidden visibility, and a weak symbol walk into a bar

When the LLVM package build with the Clang compiler's link-time optimization activated failed, the LLVM packaging team knew they had a mystery to solve.


Optimizing the Clang compiler’s line-to-offset mapping

Want Clang to compile faster? Learn why optimizing the LineOffsetMapping function was a good start, and how it was optimized for both SSE and bithacks.


Profile-guided optimization in Clang: Dealing with modified sources

Learn how the Clang compiler implements profile-guided optimization, then explore a real-world bug that shows the pitfalls of the current approach to PGO.


Toward _FORTIFY_SOURCE parity between Clang and GCC

We describe the patches applied to Clang so that -D_FORTIFY_SOURCE works as well with Clang and glibc as it does with GCC and glibc.


Customize the compilation process with Clang: Making compromises

In part two of this series, we look at compromises and tradeoffs involved in specific approaches to customizing the compilation process.


Customize the compilation process with Clang: Optimization options

Learn more about the Clang compiler and the specific flags you can use to customize the compilation process.


A look at LLVM Advanced Data Types and trivially copyable types

This article looks at various bugs in LLVM relating to trivially copyable data types and describes some potential workarounds.