Bug 271 – Incorrect constant evaluation of TypeInfo equality comparisons

Consider: writefln( typeid(int) is typeid(int) ); // prints true (Correct) writefln( typeid(int) !is typeid(int) ); // prints false (Correct) writefln( typeid(int) == typeid(Object) ); // prints 0 (Correct) writefln( typeid(int) != typeid(Object) ); // prints false! (Correct) // prints true (INCORRECT), should be 1, an int: writefln( typeid(int) == typeid(int) ); // prints true (INCORRECT), should be false: writefln( typeid(int) != typeid(int) ); // prints bool (INCORRECT), should be int writefln( typeid(typeof(typeid(int) == typeid(int))) ); The bug is in the constant folding(evaluation) system: if we the check the asm for that code then 1(true) is generated for both == and != calls. Also, the following code, which are all runtime evaluations, work correctly: auto ti = typeid(int); writefln( ti == ti ); // prints 1 (Correct) writefln( ti != ti ); // prints false (Correct) writefln( ti == typeid(int) ); // prints 1 (Correct) writefln( ti != typeid(int) ); // prints false (Correct)

Fixed DMD 0.164

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 [email protected] schrieb am 2006-07-29: > http://d.puremagic.com/issues/show_bug.cgi?id=271 > Consider: > > writefln( typeid(int) is typeid(int) ); // prints true (Correct) > writefln( typeid(int) !is typeid(int) ); // prints false (Correct) > > writefln( typeid(int) == typeid(Object) ); // prints 0 (Correct) > writefln( typeid(int) != typeid(Object) ); // prints false! (Correct) > > // prints true (INCORRECT), should be 1, an int: > writefln( typeid(int) == typeid(int) ); > // prints true (INCORRECT), should be false: > writefln( typeid(int) != typeid(int) ); > > // prints bool (INCORRECT), should be int > writefln( typeid(typeof(typeid(int) == typeid(int))) ); > > The bug is in the constant folding(evaluation) system: if we the check the asm > for that code then 1(true) is generated for both == and != calls. Also, the > following code, which are all runtime evaluations, work correctly: > > auto ti = typeid(int); > writefln( ti == ti ); // prints 1 (Correct) > writefln( ti != ti ); // prints false (Correct) > writefln( ti == typeid(int) ); // prints 1 (Correct) > writefln( ti != typeid(int) ); // prints false (Correct) http://dstress.kuehne.cn/run/t/typeid_90_A.d http://dstress.kuehne.cn/run/t/typeid_90_B.d http://dstress.kuehne.cn/run/t/typeid_90_C.d http://dstress.kuehne.cn/run/t/typeid_90_D.d http://dstress.kuehne.cn/run/t/typeid_90_E.d http://dstress.kuehne.cn/run/t/typeid_90_F.d http://dstress.kuehne.cn/run/t/typeid_90_G.d http://dstress.kuehne.cn/run/t/typeid_90_H.d http://dstress.kuehne.cn/run/t/typeid_90_I.d http://dstress.kuehne.cn/run/t/typeid_90_J.d http://dstress.kuehne.cn/run/t/typeid_90_K.d Thomas -----BEGIN PGP SIGNATURE----- iD8DBQFE4GqFLK5blCcjpWoRAhuqAKCG1Yt42B4A+KNV5Q8ayzS0SpyiLACeL7HJ BbMYlPMUE8k094gkIAip2Nc= =RMHq -----END PGP SIGNATURE-----

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Bruno Medeiros schrieb am 2006-08-14: > Thomas Kuehne wrote: >> http://dstress.kuehne.cn/run/t/typeid_90_G.d for reference the test was: # # assert(typeid(typeof(typeid(int) == typeid(int))).toString() # == typeid(typeof(args[0].length == args.length)).toString()); # > I don't think this test case is correct. You test the type-of a TypeInfo > (which is an Object) equality operation vs the type-of an int(which is a > primitive type) equality operation. Nothing says that such type-of > should be the same (even though I very much think it should). > > What I do think is not correct is the following (second line) : > > writefln( typeid(typeof(typeid(int) == typeid(char))) );// int > writefln( typeid(typeof(typeid(int) == typeid(int))) );//bool INCORRECT? > writefln( typeid(typeof(new Object == new Object)) ); // int > > writefln( typeid(typeof(typeid(int) != typeid(char))) ); // bool > writefln( typeid(typeof(typeid(int) != typeid(int))) ); // bool > writefln( typeid(typeof(new Object != new Object)) ); // bool See new issue tracker: http://d.puremagic.com/issues/show_bug.cgi?id=288 Thomas -----BEGIN PGP SIGNATURE----- iD8DBQFE4cjWLK5blCcjpWoRAqqdAJoD3bFNsF7172YrvL5GmDB9KfBQkACgrNHF 5ltSQGIWN5RhPLUmIXjTNOI= =f3zJ -----END PGP SIGNATURE-----