[PATCH 0/6] glr: fix compatibility bw %merge and api.value.type=union

[Akim Demaille]

This series cleans up a few issues in %merge management, and in
particular make `%merge` and `%define api.value.type union`
compatible.  That is the problem that Jot faced in
https://lists.gnu.org/r/help-bison/2020-12/msg00014.html.

The GLR example in C is adjusted to demonstrate both `%merge` and
`%define api.value.type union`.

Akim Demaille (6):
  %merge: clearer tests on diagnostics
  %merge: let mergers record a typing-symbol, rather than a type
  %merge: delegate the generation of calls to mergers to m4
  %merge: fix compatibility with api.value.type=union
  %merge: test support for api.value.type=union
  %merge: associate it to its first definition, not the latest

 TODO                       |  9 +++++++
 data/skeletons/glr.c       | 11 ++++++++-
 data/skeletons/glr2.cc     |  8 ++++++
 examples/c/glr/c++-types.y | 31 ++++++++++++++---------
 src/output.c               | 10 ++------
 src/reader.c               | 48 ++++++++++++++++++++----------------
 src/reader.h               |  5 +++-
 tests/README.md            | 26 ++++++++++++++++++++
 tests/glr-regression.at    | 50 ++++++++++++++++++++++++++------------
 tests/local.mk             |  4 ++-
 10 files changed, 143 insertions(+), 59 deletions(-)
 create mode 100644 tests/README.md

-- 
2.29.2