gcc-3.4.0 で、 gcc ディレクトリで grep -n '!!' * とかやった結果、

c-decl.c:3634: constp = !! (specbits & 1 << (int) RID_CONST) + TYPE_READONLY (element_type);
c-decl.c:3636: = !! (specbits & 1 << (int) RID_RESTRICT) + TYPE_RESTRICT (element_type);
c-decl.c:3638: = !! (specbits & 1 << (int) RID_VOLATILE) + TYPE_VOLATILE (element_type);
c-decl.c:3639: inlinep = !! (specbits & (1 << (int) RID_INLINE));
c-parse.c:1854:#define YYRECOVERING() (!!yyerrstatus)
collect2.c:824: no_demangle = !! getenv ("COLLECT_NO_DEMANGLE");
cppexp.c:320: result.unsignedp = !!(type & CPP_N_UNSIGNED);
cppexp.c:407: overflow = !!(num.high >> (PART_PRECISION - shift));
cppexp.c:593: result.unsignedp = !!unsignedp;
cppfiles.c:629: if (CPP_OPTION (pfile, deps.style) > !!sysp && !file->stack_count)
cppfiles.c:742: bool print_dep = CPP_OPTION (pfile, deps.style) > !!sysp;
cppspec.c:169: + !!o_here + !!lang_c_here + !!lang_S_here;
cpptrad.c:714: bool recursing = !!(node->flags & NODE_DISABLED);
expr.c:7398: return !!(the_word & bitmask); */
gcov.c:818: arc->on_tree = !!(flags & GCOV_ARC_ON_TREE);
gcov.c:819: arc->fake = !!(flags & GCOV_ARC_FAKE);
gcov.c:820: arc->fall_through = !!(flags & GCOV_ARC_FALLTHROUGH);
gengtype-yacc.c:429:#define YYRECOVERING() (!!yyerrstatus)
hard-reg-set.h:95: (!!((SET) & (HARD_CONST (1) << (BIT))))
hard-reg-set.h:125: (!!((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT]\
ra.c:431: something_spilled = !!WEBS(SPILLED);
real.c:3043: encode_ieee_extended (fmt, buf+!!FLOAT_WORDS_BIG_ENDIAN, r);
real.c:3138: decode_ieee_extended (fmt, r, buf+!!FLOAT_WORDS_BIG_ENDIAN);
一部、みやすいように、削りましたが、ほんとにろーとるなんでしょうか？？？