Subroutine and function "dummy arguments" are basically restricted references. When analyzing data dependences in the body of a subprogram, a compiler doesn't

Subroutine and function "dummy arguments" are basically restricted references. When analyzing data dependences in the body of a subprogram, a compiler doesn't have to worry about writes to one dummy argument affecting any reads to or writes from another dummy argument. The burden is on the programmer of a procedure's caller to ensure that any dummy argument that is modified during the call does not alias with any other dummy argument. This is the big one. Fortran >= 90 has ALLOCATABLE variables (and now components), which are dynamically managed objects that are akin to std::unique_ptr<> or std::vector<> smart objects. A compiler can assume that an ALLOCATABLE object is free from aliasing, unlike a POINTER. Fortran does have POINTERs, but they can only point to objects that have been explicitly tagged with the TARGET attribute. Objects that are not TARGETs are safe from aliasing with POINTERs. Fortran does still not have the concept of a pointer to immutable data. Do any of these still yield performance advantages over C/C++? Probably not.