https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109575
Bug ID: 109575
Summary: Implement runtime check for valid function result
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: anlauf at gcc dot gnu.org
Target Milestone: ---
Split off from the discussion in pr109500: consider
program main
implicit none
integer, allocatable :: p
p = f() ! <- this assignment may fail
print *, allocated (p)
contains
function f()
integer, allocatable :: f
allocate (f, source=42)
deallocate (f) ! <- this renders the function invalid
end function
end
This code is invalid as the function result must be defined:
F2018:15.6.2.2
On completion of execution of the function, the value returned is that
of its function result. If the function result is a data pointer, the
shape of the value returned by the function is determined by the shape
of the function result when the execution of the function is completed.
If the function result is not a pointer, its value shall be defined by
the function. If the function result is a pointer, on return the pointer
association status of the function result shall not be undefined.
A runtime check that can detect the failing assignment needs to check
that the function result is defined when the function returns.
