Fix nondeterministic input ordering of duplicate basenames

inputNameLinkedMap is a LinkedMap containing list of file definitions
indexed by their basenames. The first time we encounter a basename, we
create a new list and store the path to that file in fullName, and
fullName is not updated again. The problem is this path depends on
filesystem ordering (we use the path we happen to hit first).

Later on we sort the inputs list using fullName but since fullName
itself is nondeterministic this doesn't always produce the same
result.

Fix this by sorting each basename list first, then sorting using the
path of the first file in each list. Afterwards, remove
FileName::fullName and FileName::path which are no longer used
anywhere.

Author: jcowgill

src/doxygen.cpp

@@ -11140,7 +11140,7 @@ static void readDir(FileInfo *fi,
           FileName *fn=nullptr;
           if (!name.empty())
           {
-            fn = fnMap->add(name,fullName);
+            fn = fnMap->add(name);
             fn->push_back(std::move(fd));
           }
         }
@@ -11228,7 +11228,7 @@ void readFileOrDirectory(const QCString &s,
             auto fd = createFileDef(dirPath+"/",name);
             if (!name.empty())
             {
-              FileName *fn = fnMap->add(name,filePath);
+              FileName *fn = fnMap->add(name);
               fn->push_back(std::move(fd));
             }
           }
@@ -12424,12 +12424,6 @@ void searchInputFiles()
   }
 
   // Sort the FileDef objects by full path to get a predictable ordering over multiple runs
-  std::stable_sort(Doxygen::inputNameLinkedMap->begin(),
-            Doxygen::inputNameLinkedMap->end(),
-            [](const auto &f1,const auto &f2)
-            {
-              return  qstricmp_sort(f1->fullName(),f2->fullName())<0;
-            });
   for (auto &fileName : *Doxygen::inputNameLinkedMap)
   {
     if (fileName->size()>1)
@@ -12440,6 +12434,12 @@ void searchInputFiles()
         });
     }
   }
+  std::stable_sort(Doxygen::inputNameLinkedMap->begin(),
+            Doxygen::inputNameLinkedMap->end(),
+            [](const auto &f1,const auto &f2)
+            {
+              return qstricmp_sort(f1->front()->absFilePath(),f2->front()->absFilePath())<0;
+            });
   if (Doxygen::inputNameLinkedMap->empty())
   {
     warn_uncond("No files to be processed, please check your settings, in particular INPUT, FILE_PATTERNS, and RECURSIVE\n");

src/filename.h

@@ -29,15 +29,11 @@ class FileDef;
 class FileName : public std::vector< std::unique_ptr<FileDef> >
 {
   public:
-    FileName(const QCString &nm,const QCString &fn) : m_name(nm), m_fName(fn), m_pathName("tmp") {}
+    explicit FileName(const QCString &nm) : m_name(nm) {}
     QCString fileName() const { return m_name; }
-    QCString fullName() const { return m_fName; }
-    QCString path() const { return m_pathName; }
 
   private:
     QCString m_name;
-    QCString m_fName;
-    QCString m_pathName;
 };
 
 //! Custom combined key compare and hash functor that uses a lower case string in

src/tagreader.cpp

@@ -1676,7 +1676,7 @@ void TagFileParser::buildLists(const std::shared_ptr<Entry> &root)
       }
       else
       {
-        mn = Doxygen::inputNameLinkedMap->add(tfi->name,fullName);
+        mn = Doxygen::inputNameLinkedMap->add(tfi->name);
         mn->push_back(std::move(fd));
       }
       buildMemberList(fe,tfi->members);