krb5-config --libs: include rpath like MIT

tools/Makefile.am

@@ -25,6 +25,7 @@ endif
 
 subst = sed	-e "s!@PACKAGE\@!$(PACKAGE)!g" \
 		-e "s!@VERSION\@!$(VERSION)!g" \
+		-e "s!@CANONICAL_HOST\@!$(CANONICAL_HOST)!g" \
 		-e "s!@prefix\@!$(prefix)!g" \
 		-e "s!@exec_prefix\@!$(exec_prefix)!g" \
 		-e "s!@libdir\@!$(libdir)!g" \

tools/krb5-config.1

@@ -60,7 +60,9 @@ Print the exec-prefix if no
 is specified, otherwise set exec-prefix to
 .Ar dir .
 .It Fl Fl libs
-Output the set of libraries that should be linked against.
+Output the set of libraries that should be linked against.  This also
+includes rpath flags with the expectation that the C compiler is used
+for final link-edits.
 .It Fl Fl cflags
 Output the set of flags to give to the C compiler when using the
 Heimdal libraries.

tools/krb5-config.in

@@ -168,6 +168,36 @@ if test "$print_exec_prefix" = "yes"; then
     exit 0
 fi
 
+# The following rpath_flag setting code is distilled from MIT Kerberos'
+# src/config/shlib.conf.  Some of this seems ancient and likely to be
+# wrong in some cases, but right for all the cases we probably care
+# about.  Also, this will very likely be wrong depending on how the
+# caller will be doing link-edits (with what compiler-driver or
+# link-editor)!  There's no fixing this.
+#
+# In principle this doesn't belong here: application should instead use
+# krb5-config --libdir to get the directory to use for the rpath, then
+# workout the rpath flags on their own.  Of course, there's no --libdir
+# option...  And MIT's krb5-config does include rpath flags.
+#
+# Compatibility with MIT is the winning consideration for now.
+case "@CANONICAL_HOST@" in
+alpha*-dec-osf*)
+  rpath_flag='-Wl,-rpath -Wl,';;
+*-*-hpux*)
+  rpath_flag='-Wl,+b,';;
+*-*-irix* | mips-*-netbsd*)
+  rpath_flag='-Wl,-rpath -Wl,';;
+*-*-netbsd* | *-*-openbsd* | *-*-solaris*)
+  rpath_flag='-R';;
+*-*-linux* | *-*-gnu* | *-*-k*bsd*-gnu | *-*-freebsd*)
+  rpath_flag='-Wl,--enable-new-dtags -Wl,-rpath -Wl,';;
+*-*-aix*)
+  rpath_flag='-Wl,-blibpath:';;
+*)
+rpath_flag=;;
+esac
+
 if test "$do_libs" = "yes"; then
     deplibs=""
     if test "$lib_gssapi" = yes; then
@@ -208,6 +238,9 @@ if test "$do_libs" = "yes"; then
     fi
     if test X"$libdir" != X/usr/lib; then
 	lib_flags="-L${libdir} $lib_flags"
+	if test X"$rpath_flag" != X; then
+	    lib_flags="${rpath_flag}${libdir} $lib_flags"
+	fi
     fi
 
     echo ${lib_flags}