DEC directives are suppose to be treated as comments on Linux but a bug in early versions of 7.0 caused a syntax error. This issue was fixed as of the 7.0-3 release.
!DEC$ATTRIBUTES C, reference, alias:'_hello'::hello
write(*,*) "Hello, world!"
% pgf90 tmp.f -c -V7.0-2 -Mfree
PGF90-S-0134-Illegal attribute - conflict with reference (tmp.f: 2)
0 inform, 0 warnings, 1 severes, 0 fatal for hello
% pgf90 tmp.f -c -V7.0-3 -Mfree