Use flex and bison directly instead from toolchain.

[hzeller]

The flex toolchain from rules_{bison,flex} do not have a version that works on Windows.

Using these directly simplifies things as well.

Fixes #2435

[hzeller]

Hi @UebelAndre I am attempting to use your flex and bison BCR modules as they look promising to get this compiling again beyond bazel 7. The flex part works well, but looks like not all compatibility functions used in bison work on Windows yet.

https://github.com/chipsalliance/verible/actions/runs/27646448734/job/81759530364?pr=2524

(this is the corresponding windows github action).

It runs into trouble with sys/time.h or termios.h. Are you aware if there might be more autoconf flags we could use in the bison BCR that could help ?

[hzeller]

Now it looks like we're down to issues in m4; fseeko and ftello seem to be trouble-makers on Windows
https://github.com/chipsalliance/verible/actions/runs/27744063143/job/82077943587?pr=2524#step:7:18

Is there similar autoconf magic you did in bison possible in M4, @UebelAndre ?

[UebelAndre]

Yeah, I’m currently poking around at it but won’t really have bandwidth until later this week

[UebelAndre]

Can you try adding bazel_dep(name = "rules_cc_autoconf", version = "0.15.0") and see if that gets you farther?

[hzeller]

Tried that version of autoconf ... https://github.com/chipsalliance/verible/compare/54c32d5f217fe233dde39314398db232d92c6693..3db5cd884a7f2530029be3bccbf88024c6008462

... didn't make a difference @UebelAndre

[UebelAndre]

@hzeller Sorry, for the delay here. I still haven't root caused the issue. Some work is being done to introduce clang-cl and mingw toolchains to rules_cc_autoconf CI at periareon/rules_cc_autoconf#168, if you already have that infra working here, making a PR to add that there will help reveal the root cause.

[hzeller]

In the Verible CI, we do use indeed clang-cl, mostly by choosing the compiler in the .bazelrc (

verible/.bazelrc

Lines 23 to 27 in f3e4d98

	# Use clang-cl by default on Windows. MSVC has some issues with the codebase,
	# so we focus the effort for now is to have a Windows Verible compiled with
	# clang-cl before fixing the issues unique to MSVC.
	common:windows --extra_toolchains=@local_config_cc//:cc-toolchain-x64_windows-clang-cl --extra_execution_platforms=//:x64_windows-clang-cl
	common:windows --compiler=clang-cl --cxxopt=/std:c++17 --host_cxxopt=/std:c++17 --client_env=BAZEL_CXXOPTS=/std:c++17

)

What do you mean with 'making a PR there' ?