Having the same directory listed multiple times makes the --version
output needlessly complicated to visualize. This deduplication will only
work for cmake version 3.15 and above, which should be the majority of
neovim builds by now. For older cmake versions we default to the
previous behavior of listing duplicate include directories.
The build type specific flags are defined in the variables
CMAKE_C_FLAGS_<CONFIG>, where <CONFIG> can be DEBUG, RELEASE,
RELWITHDEBINFO and MINSIZEREL.
file(GENERATE) has surprising behavior as it doesn't allow different
file contents for configurations with the same file name. This results
in an error when building neovim with a multi-config generator. Use a
workaround for now where we set the build type for multi-config
generators to "Unknown".
Any logic involving CMAKE_BUILD_TYPE is automatically broken as it won't
work with multi-config generators. The only exception is if we
explicitly check whether the current generator is single-config as well.
Instead, use generator expressions or cmake variables that allows to set
options for certain build types only such as
INTERPROCEDURAL_OPTIMIZATION_<CONFIG>.
Opt to generate all headers with optimization level O2 with no debug
information for all build types as that is the simplest way to make it
behave the same for all generators.
Problem:
Dirs "config", "packaging", and "third-party" are all closely related
but this is not obvious from the layout. This adds friction for new
contributors.
Solution:
- rename config/ to cmake.config/
- rename test/config/ to test/cmakeconfig/ because it is used in Lua
tests: require('test.cmakeconfig.paths').
- rename packaging/ to cmake.packaging/
- rename third-party/ to cmake.deps/ (parallel with .deps/)
