doc: A recipe in build-unix.md does not work

[hebasto]

This does not work anymore:

Alternatively, or in addition, debugging information can be skipped for compilation. The default compile flags are
-g -O2, and can be changed with:

./configure CXXFLAGS="-O2"

However, I don't think that an immediate action should be taken. Anyway, it will be changed after migration to CMake.

[TheCharlatan]

Mmh, just needs a note to override the debug flag?

[fanquake]

This does not work

Exactly what doesn't work?

Anyway, it will be changed after migration to CMake.

This is irrelevant. We have to maintain the autotools branches for years into the future, and aren't going to leave them broken/with incorrect docs just because something else might exist.

[hebasto]

This does not work

Exactly what doesn't work?

The resulted flags still contain the -g flag.

Anyway, it will be changed after migration to CMake.

This is irrelevant. We have to maintain the autotools branches for years into the future, and aren't going to leave them broken/with incorrect docs just because something else might exist.

Right.

[fanquake]

Mmh, just needs a note to override the debug flag?

Yep, looks like that's all that's required.

[hebasto]

Mmh, just needs a note to override the debug flag?

Yep, looks like that's all that's required.

Ok. Done in #29756.