Ftnchek (short for Fortran checker) is designed to detect certain
errors in a Fortran program that a compiler usually does not.  ftnchek
is not primarily intended to detect syntax errors.  Its purpose is to
assist the user in finding semantic errors.  Semantic errors are legal
in the Fortran language but are wasteful or may cause incorrect
operation.  For example, variables which are never used may indicate
some omission in the program; uninitialized variables contain garbage
which may cause incorrect results to be calculated; and variables
which are not declared may not have the intended type.  ftnchek is
intended to assist users in the debugging of their Fortran program.
It is not intended to catch all syntax errors.  This is the function
of the compiler.  Prior to using ftnchek, the user should verify that
the program compiles correctly.

Homepage:
https://www.dsm.fordham.edu/~ftnchek/
