automatic scalar character allocation vs. automatic integer array allocation

[may_ka]

Hi there,

the code below shows a different behaviour for allocatable scalar characters vs allocatable integer arrays:

Program Test
  Implicit None
  Character(:), allocatable :: csa,csb
  integer, allocatable :: iva(:), ivb(:)
  write(*,*) "character scalar"
  write(*,*) allocated(csa), allocated(csb)
  csb=csa
  write(*,*) allocated(csa), allocated(csb)
  write(*,*) "integer vector"
  write(*,*) allocated(iva), allocated(ivb)
  ivb=iva
  write(*,*) allocated(iva), allocated(ivb)
  write(*,*) "character scalar allocated"
  csa="a";deallocate(csb)
  write(*,*) allocated(csa), allocated(csb)
  csb=csa
  write(*,*) allocated(csa), allocated(csb)
  write(*,*) "integer vector allocated"
  allocate(iva(5))
  write(*,*) allocated(iva), allocated(ivb)
  ivb=iva
  write(*,*) allocated(iva), allocated(ivb)
End Program Test

The output is:

character scalar
 F F
 F T
 integer vector
 F F
 F F
 character scalar allocated
 T F
 T T
 integer vector allocated
 T F
 T T

The result was obtain with ifort 17.0.5.

Any clarification whether this is meant to be or not is appreciated.

Cheers

[Steve_Lionel]

In the first csb=csa, where both csb and csa are initially deallocated, it's incorrect that csb becomes allocated. Since csa is deallocated, csb should remain deallocated. Please report this through the Intel Service Center.

[IanH]

The compiler can do whatever it wants, as the references to unallocated objects in the expressions on the right hand side of the assignment statements are nonconforming.

[Steve_Lionel]

Ian is correct - I was thinking of a different situation. 

[FortranFan]

ianh wrote:

The compiler can do whatever it wants,  ..

Indeed but glad that Intel Fortran compiler provides the -check run-time error checking facility:

https://software.intel.com/en-us/fortran-compiler-18.0-developer-guide-and-reference-locating-run-time-errors

https://software.intel.com/en-us/fortran-compiler-18.0-developer-guide-and-reference-check

that will lead to a run-time error for the instruction corresponding to statement on line 7 in the original post.