aef8a2c483
Fixes #177501 This PR fixes a compilation crash when using character types in OpenMP REDUCTION clauses with declare_reduction directives. The problem was that character types weren't being handled properly during OpenMP lowering. Specifically: - Missing character length parameters in hlfir.declare operations - Incorrect type wrapping for by-ref reductions - Missing special case handling for boxed/unboxed character types The fix ensures character types are treated similarly to derived types throughout the reduction pipeline, since fir::isa_trivial() excludes them. Added a regression test to verify the fix works for both allocatable and non-allocatable character reductions. <img width="654" height="47" alt="image" src="https://github.com/user-attachments/assets/cc962f01-3432-44ce-befb-324644767c8b" />
Flang
Flang is a ground-up implementation of a Fortran front end written in modern C++. It started off as the f18 project (https://github.com/flang-compiler/f18) with an aim to replace the previous flang project (https://github.com/flang-compiler/flang) and address its various deficiencies. F18 was subsequently accepted into the LLVM project and rechristened as Flang.
Please note that flang is not ready yet for production usage.
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Read more about flang in the docs directory. Start with the compiler overview.
To better understand Fortran as a language and the specific grammar accepted by flang, read Fortran For C Programmers and flang's specifications of the Fortran grammar and the OpenMP grammar.
Treatment of language extensions is covered in this document.
To understand the compilers handling of intrinsics, see the discussion of intrinsics.
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Consult the Getting Started with Flang for information on building and running flang.