[Buildroot] [PATCH] Fix issue with printvars executing giant shell command

[Yann E. MORIN <yann.morin.1998@free.fr>]

Trent, All,

On 2018-09-17 18:02 +0000, Trent Piepho spake thusly:
> On Mon, 2018-09-10 at 20:18 +0200, Yann E. MORIN wrote:
> > In a recipe, a command line that contains only spaces will not be executed
> > by make.
[--SNIP--]
> Ok, if you like that better.  My thought was "strip eats whitespace" is
> simple, but "a recipe line starting with a tab and containing only
> whitespace is skipped" is more obscure.  In fact, while it does appear
> to be true, I haven't found anything in the make docs clearly stating
> this.

From the make manual, chapter 5.1, "Recipe Syntax" [0], states:

    * A blank line that begins with a tab is not blank: it?s an empty
      recipe (see Empty Recipes).

... where "Empty Recipes" is a link to chapter 5.9, titled "Using
Empty Recipes" [1], which starts with:

    It is sometimes useful to define recipes which do nothing. This
    is done simply by giving a recipe that consists of nothing but
    whitespace.

[0] https://www.gnu.org/software/make/manual/make.html#Recipe-Syntax
[1] https://www.gnu.org/software/make/manual/make.html#Empty-Recipes

Regards,
Yann E. MORIN.

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