Pass user-defined options to build of specific userland targets?

["John D. Baker" <jdbaker%mylinuxisp.com@localhost>]

Is there a mechanism to allow user-defined options to be passed to the
build of particular userland targets?

My specific case involves bind9.  Since I run my own DNS and lack IPv6
external connectivity, I wondered if it were possible to have my name
servers drop AAAA records from recursive replies (to work around 'svn'
lossage).  Sure enough, "filter-aaaa-on-v4 yes;" would do what I wanted
but this option is not configured in the default build.  (Putting the
option in "named.conf" will cause 'named' to fail to start at all.)

Bv9ARM indicates this option is enabled via "--enable-filter-aaaa=yes"
on the command-line to the "./configure" script.  I couldn't see any
place to add configure options, so I modified the script to unconditionally
enable the option.  Following the build, the option was still not
enabled--it appears that the configure script is not used during the
build.

Since all that config option did was add "#define ALLOW_FILTER_AAAA_ON_V4"
to "confdefs.h", but no such file appeared to exist, I made the modification
shown below.  This worked and my nameservers now accept and honor the
"filter-aaaa-on-v4" option.  Is there a better/more appropriate method?
(I also don't like keeping local patches if I don't have to.)


+Index: external/bsd/bind/Makefile.inc
+===================================================================
+RCS file: /cvsroot/src/external/bsd/bind/Makefile.inc,v
+retrieving revision 1.12.4.1
+diff -u -b -r1.12.4.1 Makefile.inc
+--- external/bsd/bind/Makefile.inc     19 May 2012 15:23:41 -0000      1.12.4.1
++++ external/bsd/bind/Makefile.inc     7 Mar 2014 18:16:02 -0000
+@@ -50,6 +50,7 @@
+ 
+ .if (${USE_INET6} != "no")
+ CPPFLAGS+=    -DWANT_IPV6
++CPPFLAGS+=    -DALLOW_FILTER_AAAA_ON_V4
+ .endif
+ 
+ .if defined(HAVE_GCC)


Thanks

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