diff mbox

Tweak Negative() documentation in options.texi

Message ID g4aafuco5v.fsf@linaro.org
State Accepted
Headers show

Commit Message

Richard Sandiford April 13, 2011, 12:48 p.m. UTC 
I was looking at a backport of the current linux.opt, and got confused
by the chain of three Negative()s.  I was thinking that saying
"A is Negative(B)" was equivalent to saying A == !B.

This patch is an attempt to clarify the documentation.  Tested with
"make doc", "make html" and "make pdf".  OK to install?

Richard


gcc/
	* doc/options.texi (Negative): Explicitly mention that the
	Negative chain must be circular.
diff mbox

Patch

Index: gcc/doc/options.texi
===================================================================
--- gcc/doc/options.texi	2011-04-07 09:23:22.000000000 +0100
+++ gcc/doc/options.texi	2011-04-13 13:42:24.000000000 +0100
@@ -222,6 +222,13 @@  the option name with the leading ``-'' r
 propagate through the @code{Negative} property of the option to be
 turned off.
 
+As a consequence, if you have a group of mutually-exclusive
+options, their @code{Negative} properties should form a circular chain.
+For example, if options @option{-@var{a}}, @option{-@var{b}} and
+@option{-@var{c}} are mutually exclusive, their respective @code{Negative}
+properties should be @samp{Negative(@var{b})}, @samp{Negative(@var{c})}
+and @samp{Negative(@var{a})}.
+
 @item Joined
 @itemx Separate
 The option takes a mandatory argument.  @code{Joined} indicates