https://gcc.gnu.org/bugzilla/show_bug.cgi?id=50377
--- Comment #4 from Vittorio Zecca <zeccav at gmail dot com> ---
Still present at version 11.
The Intel ifort and NAG nagfor compilers decet the issue.
nagfor -S gfbug158.f -w
NAG Fortran Compiler Release 7.0(Yurakucho) Build 7042
Error: gfbug158.f, line 3: External procedure SUB used as actual argument but
does not have the EXTERNAL attribute
[NAG Fortran Compiler error termination, 1 error]
[vitti f95]$ifort -S gfbug158.f
gfbug158.f(3): error #7898: If an external or dummy procedure name is used as
an actual argument, its interface shall be explicit or it shall be explicitly
declared to have the EXTERNAL attribute. [SUB]
call sub(sub)
---------------^
compilation aborted for gfbug158.f (code 1)
