OS X still uses clang-14, which lacks sufficient std::ranges support for
recent Rebirth changes.
- Rewrite uses of std::ranges::SYMBOL to ranges::SYMBOL
- Add a stub header that, on gcc, provides for each SYMBOL a statement
`using std::ranges::SYMBOL;`, to delegate back to the standard library
implementation.
- On clang, define a minimal implementation of the required symbols,
without constraint enforcement. Compile-testing with gcc will catch
constraint violations.
Once OS X clang ships a standard library with the required features,
this stub header will be removed and the uses changed back to their full
names.
std::ranges::find_if permits use of a sentinel instead of a full
iterator, and supports std::ranges::find as an alternative to certain
simple uses of std::find_if.
Where possible, use the form that takes a range, rather than the form
that takes two iterators.
Add a declared, but not defined, default constructor for
self_return_iterator to satisfy the standard library's concept
`semiregular`, which insists that sentinels be default-constructible,
even for those functions that never need to do so.
Add a defined, but unused, operator++(postfix) for zip_iterator to
satisfy a standard library concept for `forward_iterator`.
clang-13 fails to sufficiently inline this construct, causing it to emit
an unnecessary call to check_null_pointer_conversion on a path where
m_ptr is already guaranteed to be non-nullptr. That call in turn
causes a linker error, since no other site using valptridx<wall> needs
check_null_pointer_conversion instantiated. Rather than provide the
instantiation, rework the logic to avoid the need for the dead call.
Define separate enum values for rotation data in both the high bits,
where it is usually kept, and the low bits, where it is sometimes used
for math or comparisons.
Define an enum value to represent the composite of the index and the
rotation, since the composite is not suitable for use as an array
subscript. Add helper functions to extract the component pieces.
gcc-4.9 support is now difficult to test due to system libraries linking
to newer symbols. gcc-4.9 is unsupported upstream, as are gcc-5 and
gcc-6. Raise the minimum required gcc version to the minimum version
supported upstream.
Debian Jessie shipped gcc-4.9.2, and support for this target was the
primary motivator for retaining gcc-4.9 support. Jessie ended regular
support in June 2018, and will end Long Term Support in June 2020. It
seems unlikely that Jessie would receive a snapshot build of Rebirth in
the months it has left.
Debian Stretch shipped gcc-6, but is currently considered "oldstable"
and has been superseded by Debian Buster. Further, Debian Stretch
provides a package for gcc-7, so Stretch users can still build Rebirth
using only packages available from the package manager.
In multiplayer, the host sends a destroy message for both sides of the
wall. `do_exploding_wall_frame` processes both, but
`num_exploding_walls` is only decreased by 1, causing an assertion
failure at the end. Remove the assertion, since the wall does not
explode instantly on join, despite being marked as WALL_EXPLODING.
