The GNU Fortran Compiler: Old-style variable initialization

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#### 5.1.2 Old-style variable initialization

GNU Fortran allows old-style initialization of variables of the form:

          INTEGER i/1/,j/2/
          REAL x(2,2) /3*0.,1./

The syntax for the initializers is as for the `DATA` statement, but unlike in a `DATA` statement, an initializer only applies to the variable immediately preceding the initialization. In other words, something like `INTEGER I,J/2,3/` is not valid. This style of initialization is only allowed in declarations without double colons (`::`); the double colons were introduced in Fortran 90, which also introduced a standard syntax for initializing variables in type declarations.

Examples of standard-conforming code equivalent to the above example are:

    ! Fortran 90
          INTEGER :: i = 1, j = 2
          REAL :: x(2,2) = RESHAPE((/0.,0.,0.,1./),SHAPE(x))
    ! Fortran 77
          INTEGER i, j
          REAL x(2,2)
          DATA i/1/, j/2/, x/3*0.,1./

Note that variables which are explicitly initialized in declarations or in `DATA` statements automatically acquire the `SAVE` attribute.