diff --git a/graphics/potrace/patches/make-check-tolerance.diff b/graphics/potrace/patches/make-check-tolerance.diff
new file mode 100644
index 0000000000..54dff3781a
--- /dev/null
+++ b/graphics/potrace/patches/make-check-tolerance.diff
@@ -0,0 +1,34 @@
+diff --git a/check/pdf-check.sh b/check/pdf-check.sh
+--- a/check/pdf-check.sh
++++ b/check/pdf-check.sh
+@@ -72,11 +72,11 @@
+     echo "GS does not understand PDF; skipping this test" >& 2
+     exit 77
+ fi 
+-actiondiff "$TMP2" "$REFDATA" 1000
++actiondiff "$TMP2" "$REFDATA" 1200
+ 
+ action $POTRACE -r50 -p -L 0 -B 0 --opaque -b pdf -o "$TMP1" "$DATA"
+ action "$GS" -q -dNOPAUSE -sDEVICE=pbmraw -g460x394 -r100x100 -sOutputFile="$TMP2" -- "$TMP1"
+-actiondiff "$TMP2" "$REFDATA" 1200
++actiondiff "$TMP2" "$REFDATA" 1600
+ 
+ action $POTRACE -r50 -p -L 0 -B 0 -A 160 -b pdf -o "$TMP1" "$DATA"
+ action "$GS" -q -dNOPAUSE -sDEVICE=pbmraw -g568x528 -r100x100 -sOutputFile="$TMP2" -- "$TMP1"
+diff --git a/check/postscript-check.sh b/check/postscript-check.sh
+--- a/check/postscript-check.sh
++++ b/check/postscript-check.sh
+@@ -70,11 +70,11 @@
+     echo "Something is wrong with $GS; skipping this test" >& 2
+     exit 77
+ fi 
+-actiondiff "$TMP2" "$REFDATA" 1000
++actiondiff "$TMP2" "$REFDATA" 1200
+ 
+ action $POTRACE -r50 -p -L 0 -B 0 --opaque -o "$TMP1" "$DATA"
+ action "$GS" -q -dNOPAUSE -sDEVICE=pbmraw -g460x394 -r100x100 -sOutputFile="$TMP2" -- "$TMP1"
+-actiondiff "$TMP2" "$REFDATA" 1200
++actiondiff "$TMP2" "$REFDATA" 1600
+ 
+ action $POTRACE -r50 -p -L 0 -B 0 -A 160 -o "$TMP1" "$DATA"
+ action "$GS" -q -dNOPAUSE -sDEVICE=pbmraw -g568x528 -r100x100 -sOutputFile="$TMP2" -- "$TMP1"
diff --git a/graphics/potrace/potrace.SlackBuild b/graphics/potrace/potrace.SlackBuild
index d4aadb4bb3..20dc9cd6a3 100644
--- a/graphics/potrace/potrace.SlackBuild
+++ b/graphics/potrace/potrace.SlackBuild
@@ -2,7 +2,7 @@
 
 # Slackware build script for potrace
 
-# Copyright 2013-2017 Kyle Guinn <elyk03@gmail.com>, USA
+# Copyright 2013-2019 Kyle Guinn <elyk03@gmail.com>
 # All rights reserved.
 #
 # Redistribution and use of this script, with or without modification, is
@@ -70,6 +70,11 @@ cd $PRGNAM-$VERSION
 chown -R root:root .
 chmod -R u+w,go-w,a+rX-st .
 
+# https://sourceforge.net/p/potrace/discussion/300717/thread/80794047/
+# plus another tolerance change.  If you still have problems with the
+# `make check` line below, feel free to comment it out.
+patch -p1 < $CWD/patches/make-check-tolerance.diff
+
 # For metric units and papersizes, use the following flags to configure:
 # --enable-metric   Use metric units (centimeters) as default
 # --enable-a4       Use A4 as the default papersize