gentoo-overlay/app-text/dvisvgm/files/dvisvgm-1.2-external_potrace.patch

Do not build potracelib if system potrace is being used.
https://bugs.launchpad.net/dvisvgm/+bug/1153182
https://bugs.gentoo.org/show_bug.cgi?id=446902

Index: dvisvgm-1.2/Makefile.am
===================================================================
--- dvisvgm-1.2.orig/Makefile.am
+++ dvisvgm-1.2/Makefile.am
@@ -5,5 +5,11 @@
 
 AUTOMAKE_OPTIONS = foreign
 EXTRA_DIST = COPYING LGPL-2.1.txt
-SUBDIRS = potracelib src tests doc 
+if HAVE_LIBPOTRACE
+SUBDIRS =
+else
+SUBDIRS = potracelib
+endif
+
+SUBDIRS += src tests doc 
 
Index: dvisvgm-1.2/configure.ac
===================================================================
--- dvisvgm-1.2.orig/configure.ac
+++ dvisvgm-1.2/configure.ac
@@ -61,6 +61,7 @@ if test "$HAVE_LIBPOTRACE" -eq 0; then
 	EXTRA_LIBS="$EXTRA_LIBS ../potracelib/libpotrace.a "
 	AC_MSG_NOTICE([Using bundled potrace library])
 fi
+AM_CONDITIONAL(HAVE_LIBPOTRACE, test "x$HAVE_LIBPOTRACE" = "x1")
 
 
 # Check how to link Ghostscript