diff --git a/source/src/BNFC/Backend/C/CFtoCPrinter.hs b/source/src/BNFC/Backend/C/CFtoCPrinter.hs
index b42b67bf..85701121 100644
--- a/source/src/BNFC/Backend/C/CFtoCPrinter.hs
+++ b/source/src/BNFC/Backend/C/CFtoCPrinter.hs
@@ -270,7 +270,7 @@ mkCFile cf groups = concat
      [
       "void bufEscapeS(const char *s)",
       "{",
-      "  while (*s) bufEscapeC(*s++);",
+      "  if (s) while (*s) bufEscapeC(*s++);",
       "}",
       "void bufEscapeC(const char c)",
       "{",
diff --git a/source/src/BNFC/Backend/CPP/PrettyPrinter.hs b/source/src/BNFC/Backend/CPP/PrettyPrinter.hs
index cedd929b..517d89c6 100644
--- a/source/src/BNFC/Backend/CPP/PrettyPrinter.hs
+++ b/source/src/BNFC/Backend/CPP/PrettyPrinter.hs
@@ -132,7 +132,7 @@ mkHFile useStl inPackage cf groups = unlines
     "",
     "  void inline bufEscape(const char *s)",
     "  {",
-    "    while (*s) bufEscape(*s++);",
+    "    if (s) while (*s) bufEscape(*s++);",
     "  }",
     "",
     if useStl then render (nest 2 $ bufAppendString "bufEscape") else "",
diff --git a/source/src/BNFC/Backend/Java/CFtoJavaPrinter15.hs b/source/src/BNFC/Backend/Java/CFtoJavaPrinter15.hs
index 3adf9dfc..bc18e599 100644
--- a/source/src/BNFC/Backend/Java/CFtoJavaPrinter15.hs
+++ b/source/src/BNFC/Backend/Java/CFtoJavaPrinter15.hs
@@ -87,6 +87,7 @@ cf2JavaPrinter packageBase packageAbsyn cf =
       "  private static void printQuoted(String s) { render(\"\\\"\" + escape(s) + \"\\\"\"); }",
       "",
       "  public static String escape(String s) {",
+      "    if (s == null) return null;",
       "    return s.replace(\"\\\\\", \"\\\\\\\\\")",
       "            .replace(\"\\t\", \"\\\\t\")",
       "            .replace(\"\\b\", \"\\\\b\")",