[PATCH 0/4] glr2.cc: fix more warnings

The CI is still red of several platforms, which is troublesome when
testing other branches.  The first and third patches address some of
them.  The other cleans up a few issues.

The CI results for these commits are available in
https://travis-ci.org/github/akimd/bison/builds/726745365.

Akim Demaille (4):
  glr2.cc: disable incorrect warnings from GCC6 to 9
  glr.cc, glr2.cc: don't publish compiler pragmas
  glr2.cc: avoid type-punning issues
  c++: variants: minor simplification

 TODO                      | 13 ++++++--
 data/skeletons/glr.cc     | 38 ++++++++++-----------
 data/skeletons/glr2.cc    | 69 +++++++++++++++++++++++++++------------
 data/skeletons/variant.hh | 12 +++----
 tests/regression.at       |  3 +-
 5 files changed, 85 insertions(+), 50 deletions(-)

-- 
2.28.0