First, thank you for this great piece of software!

I found similar bug reports like

  https://bugzilla.gnome.org/show_bug.cgi?id=138652

and it seems that the problem isn't fixed in version 1.7.6.1, since the following code makes Doxygen run out of line sync:

/** \brief find the end of a Quote

This snippet is used to find the end of a quoted string. It checks 
if the string uses escape sequences and evaluates '\\"' . It stops at 
the last double quote (if Buf[Po] isn't ASC(!"\\"") then the end of 
the buffer is reached).

*/
#define SCAN_QUOTE(Buf,Po)  /* (multi line FreeBasic #MACRO) 
  VAR esc = IIF(Buf[Po - 1] = ASC("!"), 1, 0), p = 0
  DO
    Po += 1
    SELECT CASE AS CONST Buf[Po]
    CASE 0 : EXIT DO
    CASE ASC(!"\n") : EXIT DO
    CASE ASC("\") : IF esc THEN Po += 1
    CASE ASC("""") : IF Buf[Po + 1] = ASC("""") THEN Po += 1 ELSE EXIT DO
    END SELECT
  LOOP
#ENDMACRO */ 


/** \brief find the end of a line end comment

This snippet is used to find the end of a line end comment. It 
checks for a ASC(!"\n") and evaluates line concatenations ( _ ) on 
the way. It stops at the line end (if Buf[Po] isn't ASC(!"\n") then 
the end of the buffer is reached).

*/
#define SCAN_SL_COMM(Buf,Po)  /* (multi line FreeBasic #MACRO) 
  DO
    Po += 1
    SELECT CASE AS CONST Buf[Po]
    CASE 0, ASC(!"\n") : EXIT DO
    END SELECT
  LOOP
#ENDMACRO */ 


/** \brief find the end of a multi line comment

This snippet is used to find the end of a multi line comment block. 
It stops at the characters ' and / (if Buf[Po] isn't ASC("/") then the 
end of the buffer is reached).

*/
#define SCAN_ML_COMM()  /* (multi line FreeBasic #MACRO) 
  Po += 2
  DO
    SELECT CASE AS CONST Buf[Po]
    CASE 0 : EXIT DO
    CASE ASC(!"\n") : InLines += 1
    CASE ASC("'")
      SELECT CASE AS CONST Buf[Po + 1]
      CASE 0 : EXIT DO
      CASE ASC("/") : Po += 1 : EXIT DO
      END SELECT
    END SELECT : Po += 1
  LOOP
#ENDMACRO */ 


/** \brief find the end of a word

This snippet is used to find the end of a word in the input buffer. 
Po is at the first non-word character when done.

*/
#define SCAN_WORD()  /* (multi line FreeBasic #MACRO) 
  *A = Po
  Po += 1
  DO
    SELECT CASE AS CONST Buf[Po]
    CASE ASC("0") TO ASC("9"), _
         ASC("A") TO ASC("Z"), _
         ASC("a") TO ASC("z"), ASC("_") : Po += 1
    CASE ELSE : EXIT DO
    END SELECT
  LOOP
#ENDMACRO */ 

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