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daychan
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用 vs 和 gcc 编译结果不一样怎么办

  •  
  •   daychan · 2017-10-07 14:00:02 +08:00 · 3631 次点击
    这是一个创建于 2586 天前的主题,其中的信息可能已经有所发展或是发生改变。

    今天写一个词法分析器,在 vs 下 debug 后生成运行好好的,转到 Ubuntu 用 gcc 编译一下子傻眼了,回 win 下面用 gcc 编译也是一样的结果

    这是 vs 的结果(正常): http://chuantu.biz/t6/82/1507355708x3738353725.png

    这是 gcc 的结果(无限循环): http://chuantu.biz/t6/82/1507355765x2890174166.png

    初学者,实在搞不懂为什么

    这是代码

    #include<stdio.h>
    #include<stdlib.h>
    #include<string.h>
    #include<ctype.h>
    
    int charClass;
    #define MAX_LEN 3000
    char lexeme[MAX_LEN];
    char nextChar;
    char next2Char;
    int lexLen;
    int token;
    int nextToken;
    FILE* inFile;
    
    #define LETTER 0
    #define DIGIT 1
    #define SLASH 2
    #define ASTERISK 3
    #define DQUOTE 4
    #define UNKNOWN 999
    
    enum {ABSTRACT =258,    CASE,        CATCH,       CLASS,       DEF,
    DO,          ELSE,        EXTENDS,     fALSE,       FINAL,
    FINALLY,     FOR,         FORSOME,     IF,          IMPLICIT,
    IMPORT,      LAZY,        MACRO,       MATCH,       NEW,
    nULL,        OBJECT,      OVERRIDE,    PACKAGE,     PRIVATE,
    PROTECTED,   RETURN,      SEALED,      SUPER,       THIS,
    THROW,       TRAIT,       TRY,         tRUE,        TYPE,
    VAL,         VAR,         WHILE,       WITH,        YIELD,
    UNDERLINE,    COLON,    EQU,    EQUG,    LDE,    LCO,    LPER,     GCO,    HASHTAG,    AITE,
    OPERATOR,     ID,       INTERGER,		ERROR,     SYMBOL,       COMMENT,      STRING};
    
    char* keywords[]={"abstract",    "case",        "catch",       "class",       "def",
    "do",          "else",        "extends",     "false",       "final",
    "finally",     "for",         "forSome",     "if",          "implicit",
    "import",      "lazy",        "macro",       "match",       "new",
    "null",        "object",      "override",    "package",     "private",
    "protected",   "return",      "sealed",      "super",       "this",
    "throw",       "trait",       "try",         "true",        "type",
    "val",         "var",         "while",       "with",        "yield",
    "_",    ":",    "=",    "=>",    "<-",    "<:",    "<%",     ">:",    "#",    "@",	0};
    
    void addChar()
    {
      if(lexLen <= MAX_LEN -2)
      {
          lexeme[lexLen++] = nextChar;
          lexeme[lexLen] = 0;
      }
      else
          printf("ERROR:lexeme is too long. \n" );
    }
    
    void getChar()
    {
        static int firstRun = 1;
        if(firstRun)
        {
            nextChar = getc(inFile);
            next2Char = getc(inFile);
            firstRun = 0;
        }
        else
        {
            nextChar = next2Char;
            next2Char = getc(inFile);
    
        }
    
        if(nextChar == EOF)
        {
            charClass = EOF;
        }
        else
        {
          if (nextChar == '\"')
            charClass = DQUOTE;
          else if(nextChar == '/')
            charClass = SLASH;
          else if(nextChar == '*')
            charClass = ASTERISK;
    
          else if(isalpha(nextChar))
            charClass = LETTER;
          else if(isdigit(nextChar))
            charClass = DIGIT;
          else
            charClass = UNKNOWN;
        }
    }
    
    void getNonBlank()
    {
        while (isspace(nextChar)) {
          getChar();
        }
    }
    
    int checkSymbol(char ch,char nextCh)
    {
        switch (ch) {
    	case '(':case ')':case '{':case '}':case '<':case '>':case'&':case '[': case ']':case '.':case '\\':case '_':case '=':case ':':case ';':
            addChar();
            nextToken = SYMBOL;
            break;
          case '+':case '-':case '*':case '/':
            addChar();
            nextToken = OPERATOR;
            break;
          case EOF:
            addChar();
            nextToken = EOF;
          default:
            printf("ERROR:unknown character '%c'. \n",ch );
            nextToken = ERROR;
        }
        return nextToken;
    }
    
    void checkKeywords(char* pword)
    {
        int i = 0;
        while(keywords[i]!= 0)
        {
            char* pkeyword=keywords[i];
            if(strcmp(pword,pkeyword) == 0)
            {
                nextToken = 258 + i;
                return;
            }
            i++;
        }
    }
    
    int lexer()
    {
        lexLen =0;
        getNonBlank();
        switch (charClass) {
          case DQUOTE:
            addChar();
            getChar();
            while(charClass != DQUOTE)
            {
                addChar();
                getChar();
            }
            addChar();
            getChar();
            nextToken = STRING;
            break;
          case SLASH:
            addChar();
            getChar();
            if(charClass == ASTERISK)
            {
                addChar();
                getChar();
                loop:
                while(charClass != ASTERISK)
                {
                    addChar();
                    getChar();
                }
                addChar();
                getChar();
                if(charClass == SLASH)
                {
                    addChar();
                    getChar();
                    nextToken = COMMENT;
                    break;
                }
                else goto loop;
            }
            else if(charClass == SLASH)
            {
                addChar();
                getChar();
                while(nextChar != '\n')
                {
                    addChar();
                    getChar();
                }
                nextToken = COMMENT;
                break;
            }
            else
            {
               nextToken = OPERATOR;
               break;
            }
          case ASTERISK:
            nextToken = OPERATOR;
            break;
          case LETTER:
            addChar();
            getChar();
    
            while(charClass == LETTER || charClass == DIGIT)
            {
                addChar();
                getChar();
            }
            nextToken = ID;
    
            checkKeywords(lexeme);
            break;
          case DIGIT:
            addChar();
            getChar();
            while(charClass == DIGIT)
            {
                addChar();
                getChar();
    
            }
            nextToken = INTERGER;
            break;
    
          case UNKNOWN:
              checkSymbol(nextChar,next2Char);
              getChar();
              break;
          case EOF:
              nextToken = EOF;
              lexeme[0] = 'E';
              lexeme[1] = 'O';
              lexeme[2] = 'F';
              lexeme[3] = 0;
              break;
        }
    
        printf("<%6d,   %s  >\n",nextToken,lexeme);
        return nextToken;
        memset(lexeme,0,sizeof(lexeme));
      }
    
      int main(int argc,char* argv[])
      {
        argv++;argc--;
        inFile = fopen(argv[0],"r");
        if(inFile == NULL)
        {
          printf("ERROR:cannot open file.\n" );
          exit(0);
        }
    
        getChar();
        while(nextToken != EOF)
          lexer();
    
        return 0;
      }
    
    9 条回复    2017-10-09 09:42:32 +08:00
    lcdtyph
        1
    lcdtyph  
       2017-10-07 14:09:14 +08:00 via iPhone   ❤️ 1
    没看代码,猜测一下,输入文件的行末是\r\n,在 linux 下会 fgetc 两次,win 下只有一次。
    CEBBCAT
        2
    CEBBCAT  
       2017-10-07 16:24:32 +08:00 via Android   ❤️ 1
    跑个题:代码用 gist 贴,图片可以传到 imgur
    virusdefender
        3
    virusdefender  
       2017-10-07 16:49:22 +08:00   ❤️ 1
    先单步或者 print 找到死循环的地方,然后排除换行符编码编译器优化( gcc -O0 )之类的问题。
    wevsty
        4
    wevsty  
       2017-10-07 17:25:27 +08:00   ❤️ 1
    这个问题其实是楼主应该是自己去调试的,事实上光贴代码没有测试例子有的时候也不好找到问题。
    我这里帮楼主调试了一下,我的结论是这个问题是楼主代码自己的 bug 与编译器无关。
    举例,有一个文件内容为如下内容的时候就会有 bug 了。
    '''
    t1 * t2 t3
    '''

    nextChar = '*'
    next2Char = ' '
    的时候函数返回了一个 ASTERISK,但是在 lexer 的 case ASTERISK:中没有继续读取下一个字符直接 break 了,所以就死循环了。
    coderluan
        5
    coderluan  
       2017-10-07 19:11:37 +08:00   ❤️ 1
    自己写的代码自己调试啊,gcc 的调试工具叫 gdb,用不习惯的话弄个 codeblocks 之类的 ide
    daychan
        6
    daychan  
    OP
       2017-10-09 09:41:47 +08:00 via iPhone
    @lcdtyph 谢谢啦,找到 bug 了
    daychan
        7
    daychan  
    OP
       2017-10-09 09:41:55 +08:00 via iPhone
    @virusdefender 谢谢啦,找到 bug 了
    daychan
        8
    daychan  
    OP
       2017-10-09 09:42:00 +08:00 via iPhone
    @wevsty 谢谢啦,找到 bug 了
    daychan
        9
    daychan  
    OP
       2017-10-09 09:42:32 +08:00 via iPhone
    @coderluan 谢谢啦,找到 bug 了
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