resources/sksl/errors/UnsupportedGLSLIdentifiers.rts

void fragcoord() { float x = gl_FragCoord.x; }
void fragcolor() { float r = gl_FragColor.r; }

/*%%*
name 'gl_FragCoord' is reserved
unknown identifier 'gl_FragCoord'
name 'gl_FragColor' is reserved
unknown identifier 'gl_FragColor'
*%%*/