anchor.diff:  files are named by the rules in the <<output-file-naming,Output File Naming>>
   section.
   
  +[[option-cap-e]]
   ==== `-E`
   
   `-E` tells the glslc compiler to run only the preprocessing stage. It overrides
  
positive.code: * If there is more than one `#pragma shader_stage()` directive in the same
    translation unit, all the ``stage``s specified must be the same. Otherwise,
    glslc will issue an error.
  
  [[output-file-naming]]
  === Output file naming
  
negative.code: 
  == Description
  
  === Input file languages
  
  glslc accepts both GLSL source and SPIR-V assembly files as inputs.
  
  ==== Shader stage specification
  
  glslc provides three ways to specify the shader stage of a GLSL source file:
  `-fshader-stage=<stage>`, `#pragma shader_stage(<stage>)`, and file extension.
  The `-fshader-stage=` option overrides `#pragma shader_stage()`, which overrides
  the file extension.
  