Intel® Fortran Compiler XE 13.1 User and Reference Guides
General Compiler Directives: DECLARE generates warnings for variables that have been used but have not been declared (like the IMPLICIT NONE statement). NODECLARE (the default) disables these warnings.
Is one of the following: C (or c), !, or *. (See Syntax Rules for Compiler Directives.)
The DECLARE directive is primarily a debugging tool that locates variables that have not been properly initialized, or that have been defined but never used.