commit c26c5fc4fb852098c7188e7762778c87a50771cb

Author: albert-github <albert.tests@gmail.com>

Date:   Mon Jan 7 18:48:13 2019 +0100

    issue #6749 doxygen 1.8.15 segfault

    An empty string was defined in a `` resulting in a null pointer access.

diff --git a/src/util.cpp b/src/util.cpp

index f9c2492f..9a0e513b 100644

--- a/src/util.cpp

+++ b/src/util.cpp

@@ -5444,6 +5444,7 @@ QCString escapeCharsInString(const char *name,bool allowDots,bool allowUnderscor

   static bool allowUnicodeNames = Config_getBool(ALLOW_UNICODE_NAMES);

   static GrowBuf growBuf;

   growBuf.clear();

+  if (name==0) return "";

   char c;

   const char *p=name;

   while ((c=*p++)!=0)

@@ -6962,6 +6963,7 @@ void filterLatexString(FTextStream &t,const char *str,

 QCString latexEscapeLabelName(const char *s)

 {

+  if (s==0) return "";

   QGString result;

   QCString tmp(qstrlen(s)+1);

   FTextStream t(&result);

@@ -6999,6 +7001,7 @@ QCString latexEscapeLabelName(const char *s)

 QCString latexEscapeIndexChars(const char *s)

 {

+  if (s==0) return "";

   QGString result;

   QCString tmp(qstrlen(s)+1);

   FTextStream t(&result);

@@ -7037,6 +7040,7 @@ QCString latexEscapeIndexChars(const char *s)

 QCString latexEscapePDFString(const char *s)

 {

+  if (s==0) return "";

   QGString result;

   FTextStream t(&result);

   const char *p=s;

@@ -7061,6 +7065,7 @@ QCString latexEscapePDFString(const char *s)

 QCString latexFilterURL(const char *s)

 {

+  if (s==0) return "";

   QGString result;

   FTextStream t(&result);

   const char *p=s;