issue #7436 Incorrect handling of block comments in VHDL

The search for `/*` or /*!` ended at the last `*/` in a file and thus skipping other intermediate block end and new starts. Also the intermediate code was lost see as comment.
The filter pattern used was incorrect and should have been `<"/*" (~["*"])* "*" ("*" | ~["*","/"] (~["*"])* "*")* "/">` (thanks to https://javacc.org/contrib/C.jj).
Here also the space plus one or more `*` at the end beginning of the line are still incorporated as well as multiple `*` before the colosing `*/` this is also filtered.

src/growbuf.h

@@ -47,6 +47,7 @@ class GrowBuf
                       }
     const char *get()     { return str; }
     int getPos() const    { return pos; }
+    void setPos(const int newPos) { pos = newPos; }
     char at(int i) const  { return str[i]; }
   private:
     char *str;

src/vhdljjparser.cpp

@@ -29,6 +29,7 @@
 #include "arguments.h"
 #include "types.h"
 #include "VhdlParserIF.h"
+#include "growbuf.h"
 
 using namespace vhdl::parser;
 using namespace std;
@@ -169,7 +170,7 @@ void VhdlParser::lineCount(const char* text)
 {
   for (const char* c=text ; *c ; ++c )
   {
-    yyLineNr += (*c == '\n') ;
+    if (*c == '\n') yyLineNr++;
   }
 }
 
@@ -744,3 +745,35 @@ const char *getVhdlFileName(void)
 {
   return vhdlFileName;
 }
+
+QCString filter2008VhdlComment(const char *s)
+{
+  GrowBuf growBuf;
+  const char *p=s+3; // skip /*!
+  char c,pc='\0';
+  while (*p == ' ' || *p == '\t') p++;
+  while ((c=*p++))
+  {
+    growBuf.addChar(c);
+    if (c == '\n')
+    {
+      // special handling of space followed by * at beginning of line
+      while (*p == ' ' || *p == '\t') p++;
+      while (*p == '*') p++;
+      // special attention in case character at end is /
+      if (*p == '/') p++;
+    }
+  }
+  // special attention in case */ at end of last line
+  int len = growBuf.getPos();
+  if (growBuf.at(len-1) == '/' && growBuf.at(len-2) == '*')
+  {
+    len -= 2;
+    while (growBuf.at(len-1) == '*') len--;
+    c = growBuf.at(len-1);
+    while ((c = growBuf.at(len-1)) == ' ' || c == '\t') len--;
+    growBuf.setPos(len);
+  }
+  growBuf.addChar(0);
+  return growBuf.get();
+}

src/vhdljjparser.h

@@ -83,5 +83,5 @@ void vhdlscanFreeScanner();
 
 const QList<VhdlConfNode>& getVhdlConfiguration();
 const std::vector<std::shared_ptr<Entry> >&getVhdlInstList();
-
+QCString filter2008VhdlComment(const char *s);
 #endif

vhdlparser/vhdlparser.jj

@@ -107,17 +107,17 @@ SKIP:
 // VHDL 2008 doxygen comment /*! .... */
 SKIP :
 {
-  <MULT_DOXYGEN_VHDL_COMMENT_2008 : "/*!"  (~[])* "*/" >
+  <MULT_DOXYGEN_VHDL_COMMENT_2008 : "/*!" (~["*"])* "*" ("*" | ~["*","/"] (~["*"])* "*")* "/">
   {
    {
-     QCString q(image.data());
-     q.stripPrefix("/*!");
-     q.resize(q.length()-2);
+     QCString q = filter2008VhdlComment(image.data());
      ::vhdl::parser::VhdlParser::handleCommentBlock(q.data(),TRUE);image.clear();
    }
   }
-  | <MULT_VHDL_2008_COMMENT : "/*"  (~[])* "*/" >  {::vhdl::parser::VhdlParser::lineCount(image.data());image.clear();}
-}
+  | <MULT_VHDL_2008_COMMENT : "/*" (~["*"])* "*" ("*" | ~["*","/"] (~["*"])* "*")* "/">
+    {
+      ::vhdl::parser::VhdlParser::lineCount(image.data());image.clear();}
+    }
 
 /* KEYWORDS */