[bug #56206] ifndef false positive for exported variable

[Valentin Rusu]

URL:
  <https://savannah.gnu.org/bugs/?56206>

                 Summary: ifndef false positive for exported variable
                 Project: make
            Submitted by: valir
            Submitted on: Wed 24 Apr 2019 03:47:58 PM UTC
                Severity: 3 - Normal
              Item Group: Bug
                  Status: None
                 Privacy: Public
             Assigned to: None
             Open/Closed: Open
         Discussion Lock: Any
       Component Version: 4.2.1
        Operating System: POSIX-Based
           Fixed Release: None
           Triage Status: None

    _______________________________________________________

Details:

Platforms: ArchLinux and Fedora 29

We struggled a bit with this one but here is the test case.
Please check the attached makefiles, after placing them together in the same
directory.

Test case 1:

# With the files as given here:
$ make all
make -f child.mk all
make[1]: Entering directory ....
TEST_VAR=test
make[1]: Leaving directory ....

Now go and modify the files as described in the "child.mk" comments, then run
again:

$ make all
make -f child.mk all
make[1]: Entering directory ...
TEST_VAR=
make[1]: ...

As you can see, the TEST_VAR was now empty.

We are not sure here what's the correct behavior. Does the export from the
main Makefile defines the variable? Either ways, one of the test cases shows
that we are having a bug here.

Thanks,





    _______________________________________________________

File Attachments:


-------------------------------------------------------
Date: Wed 24 Apr 2019 03:47:58 PM UTC  Name: Makefile  Size: 52B   By: valir

<http://savannah.gnu.org/bugs/download.php?file_id=46825>
-------------------------------------------------------
Date: Wed 24 Apr 2019 03:47:58 PM UTC  Name: child.mk  Size: 260B   By: valir

<http://savannah.gnu.org/bugs/download.php?file_id=46826>

    _______________________________________________________

Reply to this item at:

  <https://savannah.gnu.org/bugs/?56206>

_______________________________________________
  Message sent via Savannah
  https://savannah.gnu.org/