source - llvm-project-14.0.6.
the definition is not displayed CodeGenOptions.cpp and so with many files

CodeGenOptions.h
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CodeGenOptions.cpp
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for example, in the vs code program, using the c/c++ extension (adds intellisense navigation), the definiton is displayed from CodegenOptions.cpp
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visual studio also displays CodeGenOptions.cpp
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in my case, the problem manifests itself in the documentation in the version llvmpoject-14.0.6, but the problem also occurs in the old version in the official example
https://blog.weghos.com/llvm/llvm/clang/lib/Frontend/CodeGenOptions.cpp.html