ReAlloc

Reallocates objects to a new shape, allocating them if needed.

Declaration

Syntax

ReAlloc(alloc_arg* args)

Arguments

Argument

Description

args

one alloc_arg per object, with the new shape.

Return values

None.

Description

ReAlloc exists for automatic reallocation on assignment: when the left hand side of an assignment is an allocatable whose shape does not match the right hand side, the object has to be deallocated and allocated again. Unlike Allocate, it is not an error for the object to be allocated already.

It is generated by the compiler rather than written by a user, and the realloc_lhs member of Assignment is what asks for it.

Examples

(ReAlloc
  :args [
    (alloc_arg
      :a (Var
        :v (SymbolRef 1 "a")
      )
      :dims [
        (dimension
          :start (IntegerConstant
            :n 1
            :type (Integer
              :kind 4
            )
            :intboz_type :Decimal
          )
          :length (IntegerConstant
            :n 20
            :type (Integer
              :kind 4
            )
            :intboz_type :Decimal
          )
        )
      ]
      :codims []
      :len_expr nil
      :sym_subclass nil
      :type nil
    )
  ]
)

It comes from this complete ASR text document:

(TranslationUnit
  :symtab (SymbolTable
    :id 0
    :symbols {
      "main" (Program
        :symtab (SymbolTable
          :id 1
          :symbols {
            "a" (Variable
              :parent_symtab 1
              :name "a"
              :dependencies []
              :intent :Local
              :symbolic_value nil
              :value nil
              :storage :Default
              :type (Allocatable
                :type (Array
                  :type (Integer
                    :kind 4
                  )
                  :dims [
                    (dimension
                      :start nil
                      :length nil
                    )
                  ]
                  :physical_type :DescriptorArray
                )
              )
              :type_declaration nil
              :abi :Source
              :access :Public
              :presence :Required
              :value_attr false
              :target_attr false
              :contiguous_attr false
              :bindc_name nil
              :is_volatile false
              :is_protected false
              :pass_attr :NotMethod
              :self_argument nil
              :codims []
            )
            "p" (Variable
              :parent_symtab 1
              :name "p"
              :dependencies []
              :intent :Local
              :symbolic_value nil
              :value nil
              :storage :Default
              :type (Pointer
                :type (Integer
                  :kind 4
                )
              )
              :type_declaration nil
              :abi :Source
              :access :Public
              :presence :Required
              :value_attr false
              :target_attr false
              :contiguous_attr false
              :bindc_name nil
              :is_volatile false
              :is_protected false
              :pass_attr :NotMethod
              :self_argument nil
              :codims []
            )
            "stat" (Variable
              :parent_symtab 1
              :name "stat"
              :dependencies []
              :intent :Local
              :symbolic_value nil
              :value nil
              :storage :Default
              :type (Integer
                :kind 4
              )
              :type_declaration nil
              :abi :Source
              :access :Public
              :presence :Required
              :value_attr false
              :target_attr false
              :contiguous_attr false
              :bindc_name nil
              :is_volatile false
              :is_protected false
              :pass_attr :NotMethod
              :self_argument nil
              :codims []
            )
          }
        )
        :name "main"
        :dependencies []
        :body [
          (Allocate
            :args [
              (alloc_arg
                :a (Var
                  :v (SymbolRef 1 "a")
                )
                :dims [
                  (dimension
                    :start (IntegerConstant
                      :n 1
                      :type (Integer
                        :kind 4
                      )
                      :intboz_type :Decimal
                    )
                    :length (IntegerConstant
                      :n 10
                      :type (Integer
                        :kind 4
                      )
                      :intboz_type :Decimal
                    )
                  )
                ]
                :codims []
                :len_expr nil
                :sym_subclass nil
                :type nil
              )
            ]
            :stat (Var
              :v (SymbolRef 1 "stat")
            )
            :errmsg nil
            :source nil
          )
          (ReAlloc
            :args [
              (alloc_arg
                :a (Var
                  :v (SymbolRef 1 "a")
                )
                :dims [
                  (dimension
                    :start (IntegerConstant
                      :n 1
                      :type (Integer
                        :kind 4
                      )
                      :intboz_type :Decimal
                    )
                    :length (IntegerConstant
                      :n 20
                      :type (Integer
                        :kind 4
                      )
                      :intboz_type :Decimal
                    )
                  )
                ]
                :codims []
                :len_expr nil
                :sym_subclass nil
                :type nil
              )
            ]
          )
          (ExplicitDeallocate
            :vars [
              (Var
                :v (SymbolRef 1 "a")
              )
            ]
          )
          (Nullify
            :vars [
              (Var
                :v (SymbolRef 1 "p")
              )
            ]
          )
          (ImplicitDeallocate
            :vars [
              (Var
                :v (SymbolRef 1 "a")
              )
            ]
          )
        ]
      )
    }
  )
  :items []
)

See Also

Allocate, Assignment, ExplicitDeallocate