X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;ds=sidebyside;f=m4%2FREADME;h=a101922ba9dd149c2176f4e0a974d57e5eb266c0;hb=4a840cc773a4173ed8b642eb1597f543ef06b62c;hp=ac32e284a26aca4d081d2d6e1a684c52ed2bbf64;hpb=6f6cdc69adf07e954dd84ce8b0d37288d567b4d8;p=gnulib.git

diff --git a/m4/README b/m4/README
index ac32e284a..a101922ba 100644
--- a/m4/README
+++ b/m4/README
@@ -1,4 +1,18 @@
+Many of the files in this directory are shared between the diffutils,
+fileutils, sh-utils, and textutils packages -- and others, so if you
+change them, try to ensure that you don't break those packages.
+Unfortunately, that's hard.
+
+One way to do that is to put the modified .m4 file in each of the packages,
+run `make dist' to create a .tar.gz file, then build that package on as
+many different types of systems as possible.  Then repeat, but using the
+original version of the .m4 file.  Run configure like this each time
+`./configure --cache=config.cache' and be sure to save the following files
+from each run: config.cache config.status config.out config.h*.
+Then compare the two versions of each of those files and be prepared to
+explain any differences.
+
 These files are used by a program called aclocal (part of the GNU automake
 package).  aclocal uses these files to create aclocal.m4 which is in turn
-used by autoconf to create the configure script at the the top level in
+used by autoconf to create the configure script at the top level in
 this distribution.