Re: [9fans] Conversion of constants in C compiler

[adr <adr@SDF.ORG>]

I think I got it right at last:

[...]
        vv = yylval.vval;
        if(c1 & Numvlong ||
          (uvlong)convvtox(vv, TUVLONG) > convvtox(vv, TULONG)){
                /* unsigned suffix or hex occupying the sing bit */
                if((c1 & Numuns) || convvtox(vv, TVLONG) < 0 && (c1 & Numdec) == 0) {
                        c = LUVLCONST;
                        t = TUVLONG;
                        goto nret;
                }
                c = LVLCONST;
                t = TVLONG;
                goto nret;
        }
        if(c1 & Numlong ||
          (uvlong)convvtox(vv, TULONG) > convvtox(vv, TUINT)){
                if((c1 & Numuns) || convvtox(vv, TLONG) < 0 && (c1 & Numdec) == 0) {
                        c = LULCONST;
                        t = TULONG;
                        goto nret;
                }
                /* decimal occupying the sing bit */
                if(convvtox(vv, TLONG) < 0 && (c1 & Numdec) == 0) {
                        c = LVLCONST;
                        t = TVLONG;
                        goto nret;
                }
                c = LLCONST;
                t = TLONG;
                goto nret;
        }
        if((c1 & Numuns) || convvtox(vv, TINT) < 0 && (c1 & Numdec) == 0) {
                c = LUCONST;
                t = TUINT;
                goto nret;
        }
        if(convvtox(vv, TINT) < 0 && (c1 & Numdec) == 0) {
                c = LLCONST;
                t = TLONG;
                goto nret;
        }
        c = LCONST;
        t = TINT;
        goto nret;
[...]

I used the cast also in (uvlong)convvtox(vv, TULONG) because the
standard only specifies that long long can't be smaller than long.

After playing with this I'm thinking about using the original code
and substituting the warning for an error when a constant is
truncated. Makes sense to me and Plan9's C isn't C99 anyway.

adr.

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