$NetBSD$

Honor CFLAGS/CXXFLAGS/LDFLAGS/LIBS.

--- Jamrules.orig	2014-06-21 21:24:40.000000000 +0000
+++ Jamrules
@@ -14,11 +14,15 @@ if ! $(JAMCONFIG_READ) {
 	Exit "Can't find Jamconfig. Did you run 'configure' first?" ;
 }
 
-# by default all flags that jam uses directly are cleared
-# here should _not_ be set anything since they are filled per target
-CCFLAGS = ;
-C++FLAGS = ;
-OPTIM = ;
+
+# variables used by jam directly
+# OPTIM is cleared so it don't collide with FLAGS
+OPTIM     = ;
+CCFLAGS   = $(CFLAGS) ;
+C++FLAGS  = $(CXXFLAGS) ;
+LINKFLAGS = $(LDFLAGS) ;
+LINKLIBS  = $(LIBS) ;
+
 
 # only haiku jam
 JCACHEFILE = $(TOP)/.jamcache ;