> And yes, we do use wide tabs, because that makes indentation something you can visually see in the structure at a glance and on a whole-function basis, rather than something you have to try to visually "line up" things for or count spaces.

That is what he says

In the post he refers to "wide tabs" which means hard tabs displayed 8 chars long. This has been the standard kernel style since the beginning.

The kernel uses 8-space tabs.

How do you mean 8 space tabs? Are tabs not single characters \t?

You can customize your text editor to show them as any number of spaces. Mostly people prefer tab-stops at each forth or eighth column.

In practice you get problems, because of the line length rule.

I.e. if your editor is configured with four-space tabs and a line with one leading tab shows up in your editor having 79 characters, it will show up as 83 characters for others assuming the normal 8-space tabs thus breaking the line length rule.

Not to mention that coding style may require that function calls broken to 2 lines must have the arguments aligned at the opening parenthesis.

For example, breaking up foobarbaz(1, 2); into two lines would require having the second line start with <TAB><SPACE><SPACE>2); which would no longer look correct with 4-space tabs.

>Not to mention that coding style may require that function calls broken to 2 lines must have the arguments aligned at the opening parenthesis.

That doesn't result in any problems with using <TAB>s, unless the coding style also requires you to replace all (leading) sequences of N spaces with with a <TAB>, which is, IMO, quite brain-dead. For example,

    if (cond) {
    <TAB>foo(1,
    <TAB><SP><SP><SP><SP>2);
    }

looks fine regardless of the width of <TAB>.

Admittedly, your first problem remains; a problem with dumb editors. In truth, your editor could well signal if your lines exceed the limit (indent-width*indent + rest) you have set for your project, just as easily as it can draw a line at a column.

The harder problem is that you need a context-aware editor for it to help you with indenting. Most editors are incapable of that by default.

> unless the coding style also requires you to replace all (leading) sequences of N spaces with with a <TAB>, which is, IMO, quite brain-dead

It is brain-dead, but that is exactly what is required in many styles.