小弟想做个C\C++编译器，请们给点意见

小弟想做个C\C++编译器，请大虾们给点意见~
小弟想做个编译器，不知各位大虾有什么好的建议？谢谢~

------解决方案--------------------
ANSI C grammar, Lex specification
In 1985, Jeff Lee published this Lex specification together with a Yacc grammar for the April 30, 1985 ANSI C draft. Tom Stockfisch reposted both to net.sources in 1987; that original, as mentioned in the answer to question 17.25 of the comp.lang.c FAQ, can be ftp 'ed from ftp.uu.net, file usenet/net.sources/ansi.c.grammar.Z.
I intend to keep this version as close to the current C Standard grammar as possible; please let me know if you discover discrepancies.

Jutta Degener, 1995


--------------------------------------------


D [0-9]
L [a-zA-Z_]
H [a-fA-F0-9]
E [Ee][+-]?{D}+
FS (f|F|l|L)
IS (u|U|l|L)*

%{
#include <stdio.h>
#include "y.tab.h "

void count();
%}

%%
"/* " { comment(); }

"auto " { count(); return(AUTO); }
"break " { count(); return(BREAK); }
"case " { count(); return(CASE); }
"char " { count(); return(CHAR); }
"const " { count(); return(CONST); }
"continue " { count(); return(CONTINUE); }
"default " { count(); return(DEFAULT); }
"do " { count(); return(DO); }
"double " { count(); return(DOUBLE); }
"else " { count(); return(ELSE); }
"enum " { count(); return(ENUM); }
"extern " { count(); return(EXTERN); }
"float " { count(); return(FLOAT); }
"for " { count(); return(FOR); }
"goto " { count(); return(GOTO); }
"if " { count(); return(IF); }
"int " { count(); return(INT); }
"long " { count(); return(LONG); }
"register " { count(); return(REGISTER); }
"return " { count(); return(RETURN); }
"short " { count(); return(SHORT); }
"signed " { count(); return(SIGNED); }
"sizeof " { count(); return(SIZEOF); }
"static " { count(); return(STATIC); }
"struct " { count(); return(STRUCT); }
"switch " { count(); return(SWITCH); }
"typedef " { count(); return(TYPEDEF); }
"union " { count(); return(UNION); }
"unsigned " { count(); return(UNSIGNED); }
"void " { count(); return(VOID); }
"volatile " { count(); return(VOLATILE); }
"while " { count(); return(WHILE); }

{L}({L}|{D})* { count(); return(check_type()); }

0[xX]{H}+{IS}? { count(); return(CONSTANT); }
0{D}+{IS}? { count(); return(CONSTANT); }
{D}+{IS}? { count(); return(CONSTANT); }
'(\\.|[^\\ '])+ ' { count(); return(CONSTANT); }

{D}+{E}{FS}? { count(); return(CONSTANT); }
{D}* ". "{D}+({E})?{FS}? { count(); return(CONSTANT); }
{D}+ ". "{D}*({E})?{FS}? { count(); return(CONSTANT); }

\ "(\\.|[^\\ "])*\ " { count(); return(STRING_LITERAL); }

"... " { count(); return(ELLIPSIS); }
"> > = " { count(); return(RIGHT_ASSIGN); }
" < <= " { count(); return(LEFT_ASSIGN); }
"+= " { count(); return(ADD_ASSIGN); }
"-= " { count(); return(SUB_ASSIGN); }
"*= " { count(); return(MUL_ASSIGN); }
"/= " { count(); return(DIV_ASSIGN); }
"%= " { count(); return(MOD_ASSIGN); }
"&= " { count(); return(AND_ASSIGN); }