Bug 5165 – compiler add a cast and then complain that the cast have no effect, giving no .o file

I try to compile, with dmd 1.065 the following: --- struct u64_t{ uint lo; uint hi; }; bool is_zero64(u64_t i) {i.hi==0 && i.lo==0;} --- but I get: [paul@Arcturus ~]$ dmd -c test.d test.d(7): Error: == has no effect in expression (i.lo == cast(uint)0) test.d(7): Error: function test.is_zero64 expected to return a value of type bool [paul@Arcturus ~]$ and I don't seems to find a way to rewrite this without the compiler refusing it.

(In reply to comment #0) > I try to compile, with dmd 1.065 the following: > > --- > struct u64_t{ > uint lo; > uint hi; > }; > > bool is_zero64(u64_t i) {i.hi==0 && i.lo==0;} > --- > > but I get: > [paul@Arcturus ~]$ dmd -c test.d > test.d(7): Error: == has no effect in expression (i.lo == cast(uint)0) > test.d(7): Error: function test.is_zero64 expected to return a value of type > bool > [paul@Arcturus ~]$ > > and I don't seems to find a way to rewrite this without the compiler refusing > it. sure you didn't mean bool is_zero64(u64_t i) {return i.hi==0 && i.lo==0;} ?

You are right... I had come to think that the value returned by a function was the last expression evaluated, and then concluded that the return could be removed... but it seems it is not true.