从全是分号的VSStudio获取C2628奇怪错误

Question

我使用的是embedFiglet，一个可嵌入的Figlet版本。虽然我在Os X上编译没有问题，但在Windows 10和VS上，我收到了一个

..\dep\embedfiglet\src\Figlet.hh(341): error C2628: 'Figlet::Banner' followed by 'char' is illegal (did you forget a ';'?)
..\dep\embedfiglet\src\Figlet.hh(341): warning C4091: 'extern ': ignored on left of 'Figlet::Banner' when no variable is declared
ninja: build stopped: subcommand failed.

CXX编译器标识为MSVC 19.16.27026.1

代码如下：

#ifndef FIGLET_HH
#define FIGLET_HH

#include <iostream>
#include <stdint.h>

/*! \brief
 * Collects structures and classes for banner generation
 */
namespace Figlet {

  using namespace std;

  typedef std::basic_ostream<char> ostream_type;

  static unsigned const maxHeight    = 10;  //!< maximum allowed (lines) height of the font 
  static unsigned const maxLenght    = 256; //!< maximum number of characters x line of the banner
  static unsigned const maxTableSize = 256; //!< maximum number of allowed character x font

  //! Structure used to store a charater of the font
  typedef struct {
    unsigned short nchar;              //!< character (ascii) number
    uint8_t        lspaces[maxHeight]; //!< number of spaces on the left side x line
    uint8_t        rspaces[maxHeight]; //!< number of spaces on the right side x line
    char const *   rows[maxHeight];    //!< charater definition
  } FontFiglet;

  //! Available way to print a string, see \ref printmode
  typedef enum {
    FIGLET_SMUSHED=0,
    FIGLET_PACKED,
    FIGLET_FULLWIDTH,
    FIGLET_MONOSPACED
  } PrintMode;

  //! Available way to print a frames string, see \ref framemode
  typedef enum { FIGLET_SINGLE=0, FIGLET_DOUBLE } FrameMode;

  //! Class implementing the "figlet" algorithm
  class Banner {

    FontFiglet const * characters; //!< pointer to the font structures
    char       const   Hardblank;  //!< character used for the "hardblank" in the font definition
    unsigned   const   Height;     //!< vertical dimension (lines) of the font
    unsigned           Width;      //!< width of the charater M used in Monospaced print
    unsigned   const   FontMaxLen; //!< maximum width of the letters of the font
    unsigned   const   FontSize;   //!< total number of characters in the font
    uint8_t            rspaces[maxHeight]; //!< extra right spaces availables after the last insertion
    char               lines[maxHeight][maxLenght]; //!< lines buffer 
    char               smush[maxHeight];            //!< charater used in the "smushing" algorithm
    unsigned short     charToTable[maxTableSize];   //!< map ascii character to font structure
    unsigned short     charWidth[maxTableSize];     //!< size width of each charater of the font
    unsigned           charPosition;                //!< position of last inserted character

    PrintMode          printMode; //!< the type of printing mode used

    Banner const & operator = ( Banner const & );
    Banner( Banner const & );

    //! evaluate smushing rules for 2 characters, return '\0' if no rules apply
    char smushingRules( char left, char right ) const;

    bool pushMonospaced( unsigned c );
    bool pushFullWidth( unsigned c );
    bool pushPacked( unsigned c );
    bool pushSmushed( unsigned c );
    void fillForPrint( char const message[] );

  public:

    //! Constructor of `Banner` class
    /*!
    :|: \param characters none
    :|: \param Hardblank  none
    :|: \param Height     none
    :|: \param FontMaxLen none
    :|: \param FontSize   none
    \*/
    explicit
    Banner( FontFiglet const * characters,
            char               Hardblank,
            unsigned           Height,
            unsigned           FontMaxLen,
            unsigned           FontSize );

    //! initialize Banner class
    void init();

    //! Set print mode to `monospaced`, see \ref printmode
    void setMonospaced() { printMode = FIGLET_MONOSPACED; }

    //! Set print mode to `full width`, see \ref printmode
    void setFullWidth() { printMode = FIGLET_FULLWIDTH; }

    //! Set print mode to `packed`, see \ref printmode
    void setPacked() { printMode = FIGLET_PACKED; }

    //! Set print mode to `smushed` (figlet default), see \ref printmode
    void setSmushed() { printMode = FIGLET_SMUSHED; }

    //! Print large letters of string `message` on stream `s`, see \ref printmode
    unsigned
    print(
      char const     message[],
      ostream_type & s        = cout,
      char const     top[]    = "",
      char const     bottom[] = ""
    );

    //! \ref framemode
    void
    printFramed(
      char const     message[],
      ostream_type & s  = cout,
      FrameMode      fm = FIGLET_SINGLE
    );
  };

  extern Banner big;      //!< instance `Banner` class using figlet font `big`
  extern Banner banner;   //!< instance `Banner` class using figlet font `banner`
  extern Banner doom;     //!< instance `Banner` class using figlet font `doom`
  extern Banner larry3d;  //!< instance `Banner` class using figlet font `larry3d`
  extern Banner mini;     //!< instance `Banner` class using figlet font `mini`
  extern Banner script;   //!< instance `Banner` class using figlet font `script`
  extern Banner small;    //!< instance `Banner` class using figlet font `small`
  extern Banner standard; //!< instance `Banner` class using figlet font `standard`
  extern Banner straight; //!< instance `Banner` class using figlet font `straight`
  extern Banner bulbhead; //!< instance `Banner` class using figlet font `bulbhead`

};

#endif

//
// eof: Figlet.hh
//

(第341行是带有"extern Banner small；“的那行)

现在，除非我的眼睛摇摇晃晃，否则我会看到所有的分号。我是Windows环境的新手，所以我猜问题一定出在别的地方。就在一周前，我已经能够正确编译。啊，真灵。现在不会再有了。

能不能请你们中更有经验的人帮我照亮一下？

Answer 1

只需使用goldbolt网站独立测试编译这段代码，Visual Studio (MSVC)和Clang都能正常工作。

我猜您可能在文件中的其他地方(或在包含的头文件中)定义了" small“到"char”(或沿着这些行的内容)，但您没有在粘贴的代码部分中显示(您是否也单独测试了这一小部分？)。