Re: Odd error with access to derived types

[Brian May <bam@snoopy.apana.org.au>]

>>>>> "Stephen" == Stephen Leake <stephen_leake@acm.org> writes:

    Stephen> A.Imran <me5@privacy.net> writes:
    >> Thank you for looking at the code.  Here is the error message:
    >> 
    >> ~> gnatmake test gcc -c test.adb parent-child.ads:10:09:
    >> "derived_access" conflicts with declaration at line 6 gnatmake:
    >> "test.adb" compilation error

    Stephen> That is certainly a confusing error message. I'd call it
    Stephen> a compiler bug; submit this to report@gnat.com.

Was the previous code valid? If not, why not?

    Stephen> As for working around it, this compiles: package parent
    Stephen> is

Another three work arounds I found:

a) move definition of derived_access after derived_type (i.e. make it private).

b) make definition of derived_type public.

It would appear that derived_access needs the full definition of
derived_type in order to work because it contains a task. I don't
understand why.

c) make dummy_task an access type to a_task.


My preference would be c), although you could argue you shouldn't need
to use or manipulate access types here.


gcc-3.4 also has the same problem:

[519] [snoopy:bam] ~/abc >gnatmake test
gcc-3.4 -c test.adb
parent-child.ads:9:09: "derived_access" conflicts with declaration at line 5
gnatmake: "test.adb" compilation error
-- 
Brian May <bam@snoopy.apana.org.au>