Here, glslang proper means core GLSL parsing, HLSL parsing, and SPIR-V code
generation. Glslang proper requires use of a number of licenses, one that covers
preprocessing and others that covers non-preprocessing.

Bison was removed long ago. You can build glslang from the source grammar,
using tools of your choice, without using bison or any bison files.

Other parts, outside of glslang proper, include:

- gl_types.h, only needed for OpenGL-like reflection, and can be left out of
  a parse and codegen project.  See it for its license.

- update_glslang_sources.py, which is not part of the project proper and does
  not need to be used.

- the SPIR-V "remapper", which is optional, but has the same license as
  glslang proper

- Google tests and SPIR-V tools, and anything in the external subdirectory
  are external and optional; see them for their respective licenses.

--------------------------------------------------------------------------------

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   Bison implementation for Yacc-like parsers in C

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================================================================================
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The preprocessor has the core licenses stated above, plus an additional licence:

Copyright (c) 2002, NVIDIA Corporation.

NVIDIA Corporation("NVIDIA") supplies this software to you in
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In consideration of your agreement to abide by the following terms, and
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Neither the name, trademarks, service marks nor logos of NVIDIA
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Except as expressly stated in this notice, no other rights or licenses
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