How do C self-hosts itself? -

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anyone knows complete chain of operations .c source code executable .exe?

i've downloaded source of gcc,and found c-parser.y written in c:

extdef:     fndef     | datadef     | asm_keyword '(' expr ')' ';'         { strip_nops ($3);           if ((tree_code ($3) == addr_expr                && tree_code (tree_operand ($3, 0)) == string_cst)               || tree_code ($3) == string_cst)             assemble_asm ($3);           else             error ("argument of `asm' not constant string"); }     | extension extdef         { pedantic = $<itype>1; }     ;

so knows complete story of c's self-hosting?

update

i know how compilers scripts written,most of them depends on c compilers.

so i'm asking how c compiler works.

gcc has multi-stage process, starts working c compiler (which might or might not version of gcc).

  1. use other c compiler create first version of gcc - gnu c compiler.
    • this gives working copy of new version of gcc (assuming old compiler serviceable).
    • it not, however, identical compiler (the new version of) gcc produce, except implausible accident.
  2. use first version of gcc create second version of gcc.
    • the second version of gcc (obviously) code gcc generate. benchmark version.
    • however, has not yet been shown stable.
  3. use second version of gcc create third version of gcc.
    • the second version of gcc should produce same output third version of gcc.
  4. ensure second , third versions of gcc same.
    • on platforms, object files contain compilation times; clearly, compilation time has discount differences in compilation time.
    • assuming second , third versions 'the same', know gcc can produce own source code.
    • it safe use new version of gcc build various runtime libraries, , other compilers in family.
  5. build other parts of gnu compiler collection new c compiler.
    • most people not restrict gnu compiler collection c compiler.
    • typically, produce c++ , java (and objective c) compilers too.
    • and need standard c++ library support too.
    • usually, c compiler uses c library provide platform.

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