On 8 July 2015 at 20:03, David Malcolm <dmalcolm@redhat.com> wrote:
> On Wed, 2015-07-08 at 20:01 +0100, Dibyendu Majumdar wrote:
>> On 8 July 2015 at 18:46, David Malcolm <dmalcolm@redhat.com> wrote:
>> > Dibyendu: what Lua code generated the reproducer?  What is the code
>> > meant to be doing?
>> >
>>
>> Hi Dave - the Lua test is this:
>>
>> function x()
>>   local IX
>>   if ((10 or true) and false) then
>>     IX = true
>>   end;
>>   return ((10 or true) and false)
>> end
>> assert(x() == false)
>>
>> In the original test IX is an upvalue - i.e. a variable in outer
>> scope. This is my standalone version of the test. The original test is
>> generated as part of the Lua test suite - its purpose is to test
>> various permutations of boolean operators.
>>
>> The original test compares IX and the function return.
>>
>> The issue is that this test should return false - if you see the
>> return statement. However when -O2 or -O3 is enabled it returns true.
>>
>> The if statement is indeed redundant in this cut down version as IX is
>> a local variable. But the return statement is not redundant.
>
> Thanks.  What does this look like as bytecodes?
>

Ok the bug is still there - I was running the test incorrectly. I have
attached the standalone replication and the output.
Note that if I remove the redundant if statement then it works correctly.

Regards
Dibyendu