I have used this debugger in the past, and it supported very well the small part of modern fortran (i.e. its subset of f2003) that was allowed by the compiler. However, the compiler is now no longer supported, so I would not recommend building in any significant dependence on it in current fortran codes. ABSOFT ceases operation on Sept. 30, 2022
Is there any recent news about support/availability of the ABSOFT tools, including Fx3?