this is kind of hacky, but automake doesn't make this easy
for us atm, so hack away :(

(recent autotools will always add $(CFLAGS)/etc... to the compile)

posted upstream:
https://marc.info/?l=linux-nfs&m=136416341629788&w=2
Date: Sun, 24 Mar 2013 22:21:08 +0000
Message-ID: 1364163668-15490-1-git-send-email-vapier@gentoo.org

From 269ae1346d9ccc97304205066d20e7e7b638f30e Mon Sep 17 00:00:00 2001
From: Mike Frysinger <vapier@gentoo.org>
Date: Sun, 24 Mar 2013 18:14:48 -0400
Subject: [PATCH nfs-utils] locktes/rpcgen: tweak how we override compiler settings

Newer autotools will use both CFLAGS and <target>_CFLAGS when compiling
the <target>.  Adding the build settings to the target-specific flags no
longer works as a way to compile build-time tools.

Instead, clobber the global flags.  This triggers an automake warning,
but the end result actually works (unlike the existing code).

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

--- a/tools/locktest/Makefile.am
+++ b/tools/locktest/Makefile.am
@@ -1,12 +1,11 @@
 ## Process this file with automake to produce Makefile.in
 
 CC=$(CC_FOR_BUILD)
-LIBTOOL = @LIBTOOL@ --tag=CC
+CFLAGS=$(CFLAGS_FOR_BUILD)
+CPPFLAGS=$(CPPFLAGS_FOR_BUILD)
+LDFLAGS=$(LDFLAGS_FOR_BUILD)
 
 noinst_PROGRAMS = testlk
 testlk_SOURCES = testlk.c
-testlk_CFLAGS=$(CFLAGS_FOR_BUILD)
-testlk_CPPFLAGS=$(CPPFLAGS_FOR_BUILD)
-testlk_LDFLAGS=$(LDFLAGS_FOR_BUILD)
 
 MAINTAINERCLEANFILES = Makefile.in
--- a/tools/rpcgen/Makefile.am
+++ b/tools/rpcgen/Makefile.am
@@ -1,7 +1,9 @@
 ## Process this file with automake to produce Makefile.in
 
 CC=$(CC_FOR_BUILD)
-LIBTOOL = @LIBTOOL@ --tag=CC
+CFLAGS=$(CFLAGS_FOR_BUILD)
+CPPFLAGS=$(CPPFLAGS_FOR_BUILD)
+LDFLAGS=$(LDFLAGS_FOR_BUILD)
 
 noinst_PROGRAMS = rpcgen
 rpcgen_SOURCES = rpc_clntout.c rpc_cout.c rpc_hout.c rpc_main.c \
@@ -9,10 +11,6 @@
 		 rpc_util.c rpc_sample.c rpc_output.h rpc_parse.h \
 		 rpc_scan.h rpc_util.h
 
-rpcgen_CFLAGS=$(CFLAGS_FOR_BUILD)
-rpcgen_CPPLAGS=$(CPPFLAGS_FOR_BUILD)
-rpcgen_LDFLAGS=$(LDFLAGS_FOR_BUILD)
-rpcgen_LDADD=$(LIBTIRPC)
 
 MAINTAINERCLEANFILES = Makefile.in
 
 EXTRA_DIST = rpcgen.new.1