Merge topic 'fix-warnings'

75e8173322 Source: Fix clang -Wunused-but-set-variable warnings
2646d5dfcf LexerParser: Suppress clang -Wunused-but-set-variable warnings
8add899c03 LexerParser: Regenerate parsers with bison 3.8.2

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: buildbot <buildbot@kitware.com>
Merge-request: !7147