Re: -MD and -MMD

[Neil Booth <neil at daikokuya dot demon dot co dot uk>]

Tom Tromey wrote:-

> I've noticed that neither -MD nor -MMD is documented in invoke.texi.
> Is this intentional?  I'm worried that this lack of documentation
> might mean that these switches are deprecated.  If that's the case,
> I'd like to argue against deprecating them.

No, a mistake.  I'd removed them from invoke.texi, thinking it was
cpp.texi because they mentioned a @var{file} in the documentation.  I
noticed this mistake yesterday, but just hadn't gone round to putting
it back.  Fixed below.

I'm quite happy to support -MD and -MMD from the drivers, but wish to
deprecate the argument-taking versions handled by the stand-alone
preprocessors.  They are no longer documented.
 
> I've also noticed that the long forms of these options
> (--write-dependencies and --write-user-dependencies) are not mentioned
> in the docs.
> 
> If this is just an oversight I'd like to know; I'll submit a patch.

I'll leave this bit to you.

Neil.

	* invoke.texi: Restore the drivers' switches -MD and -MMD.

Index: invoke.texi
===================================================================
RCS file: /cvs/gcc/gcc/gcc/invoke.texi,v
retrieving revision 1.260
diff -u -p -r1.260 invoke.texi
--- invoke.texi	2001/01/10 21:40:13	1.260
+++ invoke.texi	2001/01/11 18:20:58
@@ -3317,6 +3317,25 @@ Like @samp{-M}, but mention only the fil
 "@var{file}"}.  System header files included with @samp{#include
 <@var{file}>} are omitted.
 
+@item -MD
+@findex -MD
+Like @samp{-M} but the dependency information is written to a file
+rather than stdout.  @code{gcc} will use the same file name and
+directory as the object file, but with the suffix ".d" instead.
+
+This is in addition to compiling the main file as specified ---
+@samp{-MD} does not inhibit ordinary compilation the way @samp{-M} does,
+unless you also specify @samp{-MG}.
+
+With Mach, you can use the utility @code{md} to merge multiple
+dependency files into a single dependency file suitable for using with
+the @samp{make} command.
+
+@item -MMD @var{file}
+@findex -MMD
+Like @samp{-MD} except mention only user header files, not system
+-header files.
+
 @item -MF @var{file}
 @findex -MF
 When used with @samp{-M} or @samp{-MM}, specifies a file to write the