Changes to m4/HACKING,v

[Eric Blake]

CVSROOT:        /sources/m4
Module name:    m4
Changes by:     Eric Blake <ericb>      07/04/10 14:39:41

Index: HACKING
===================================================================
RCS file: /sources/m4/m4/HACKING,v
retrieving revision 1.9
retrieving revision 1.10
diff -u -b -r1.9 -r1.10
--- HACKING     1 Dec 2006 16:38:32 -0000       1.9
+++ HACKING     10 Apr 2007 14:39:40 -0000      1.10
@@ -38,6 +38,14 @@
   environment or the -G option was passed on the command line):
     http://www.opengroup.org/onlinepubs/009695399/utilities/m4.html
 
+* Except for third-party files (libtool, gnulib, ...), all .c files
+  should #include <config.h> before anything else (since there are some
+  #defines in config.h that potentially impact system headers, such as
+  when the user does ./configure --disable-assert).  This means that no
+  .h files need to #include <config.h>.  However, users compiling
+  external modules should be able to compile without <config.h>, since
+  <config.h> is specific to the M4 build and is not installable.
+
 
 3. Bootstrapping
 ================