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Bug 67856

Summary: experimental m4 feature hardcoded in ebuild
Product: Gentoo Linux Reporter: Stefan Sperling <stsp>
Component: Current packagesAssignee: Gentoo's Team for Core System packages <base-system>
Status: RESOLVED CANTFIX    
Severity: normal    
Priority: High    
Version: unspecified   
Hardware: x86   
OS: Linux   
Whiteboard:
Package list:
Runtime testing required: ---
Bug Depends on:    
Bug Blocks: 78817    
Attachments: proposed patch to m4-1.4-r1.ebuild

Description Stefan Sperling 2004-10-17 03:47:51 UTC
I had trouble using an autoconf binary I compiled on my gentoo system
on another (non-gentoo) machine. Using this autoconf binary, I could
not compile automake on the other machine. It complained about
autoconf not working.

I traced the error back to m4:
NONE:0: /usr/bin/m4: `changeword' from frozen file not found in builtin table!

The above error is reported by a non-gentoo m4 binary I have compiled myself.

This is what the m4 info page says about 'changeword':

     The macro `changeword' and all associated functionnality is
     experimental.  It is only available if the `--enable-changeword'
     option was given to `configure', at GNU `m4' installation time.
     The functionnality might change or even go away in the future.
     _Do not rely on it_.  Please direct your comments about it the
     same way you would do for bugs.

Autoconf creates a few frozen m4 (*.m4f) files when it is being build.
Apparently, when it uses an m4 binary with changeword support to
create these frozen files, m4 binaries lacking changeword support
cannot use them.

m4-1.4-r1.ebuild harcodes the --enable-changeword option.
imho there should be a USE flag for m4 changeword support,
as this is not a stable feature.

Here is another quote from the m4 info page, that should worry
optimisation concerned gentoo users ;-)
   
   You should note that using `changeword' will slow `m4' down by a
   factor of about seven.
Comment 1 Stefan Sperling 2004-10-17 03:49:10 UTC
Created attachment 42021 [details, diff]
proposed patch to m4-1.4-r1.ebuild
Comment 2 Stefan Sperling 2004-10-17 04:01:30 UTC
Ooops, 1.4-r1 is not the newest version of m4 in portage.
But m4-1.4.1.ebuild has the same issue.
Comment 3 Stefan Sperling 2004-10-17 04:10:36 UTC
The patch I proposed has a severe problem: it removes changeword support
by default, which would pretty likely break autoconf on any running gentoo installation.
It should disable changeword only if -changeword is set in USE instead.
Comment 4 Jakub Moc (RETIRED) gentoo-dev 2006-07-23 06:40:36 UTC
Someone should perhaps WONTFIX this?
Comment 5 SpanKY gentoo-dev 2006-11-05 01:06:07 UTC
looks like we backed ourselves into a wall with this ... if you turn off the feature then a lot of things that were generated with it will break