Before, we did set cxx version to c++17 using COPTS in our bazel files.
This was wrong, and part of the dependencies were then built with the
default standard version. This was not an issue until we moved to c++17.
Then, we decided to use the bazel --cxxopt=-std=c++17, but this was only
valid for nix platforms.
The last option left is to ask the user to specify the standard
when building using bazel.
This commit changes the way bazel chooses which version to build.
Before, we had a COPT set to -std=c++17, which is analogous to the cmake
way.
However, googletest decided to follow abseil, meaning this is *not*
recommended at all, and causes a mixed-standard build.
From https://github.com/abseil/abseil-cpp/blob/master/FAQ.md#how-to-i-set-the-c-dialect-used-to-build-abseil
we have 3 options to define the standard. Using a bazelrc is what I
believe to be the simplest, as it "fixes" the repo standard.
Signed-off-by: Nathan Gauër <brioche@google.com>
