Date: Mon, 26 Apr 1999 12:16:23 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: Shawn Hargreaves <ShawnH AT Probe DOT co DOT uk>
cc: djgpp AT delorie DOT com
Subject: Re: Why are tabs required in makefiles?
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On Mon, 26 Apr 1999, Shawn Hargreaves wrote:

> I wonder how many things would break if make automatically collapsed
> 8 leading spaces into a tab character?

Too much, it turns out.

In addition to be a Posix requirement, it turns out that many Makefiles 
use the following style of defining variables:

                  foo = bar
               foobar = barfoo
             yadayada = dayadaya

etc.--you get the idea.

Significantly the entire X project uses this style, and the imake utility 
produces it.  It is obvious that collapsing 8 spaces into a TAB will 
break those Makefiles.

The next version of Make will output a more explicit message when 8 
spaces are seen at the beginning of the line, suggesting that perhaps
the luser meant a TAB.  I hope this will serve as a stopgap.