proposal for compilation unil wide alias analyis

[Robert Dewar]

Dale Johannesen wrote:

>> For example the following program is illegal:
>>
>> subroutine foo (a, b)
>>   integer a, b
>>   ! This invokes undefined behaviour if the same actual argument
>>   ! is passed for a and b
>>   a = 1
>>   print *, b
>> end subroutine

isn't it the case that the above is wrong even if there is no
reference to b. I know that at least in earlier versions of
Fortran, the error occurs at the point where you do an assignment
to a variable which has a visible alias.