[src/trunk]: src/doc Expand the weak-symbol section to mention module unload ...

[pgoyette <pgoyette%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e77bcb2e40c3
branches:  trunk
changeset: 447030:e77bcb2e40c3
user:      pgoyette <pgoyette%NetBSD.org@localhost>
date:      Fri Dec 28 21:51:49 2018 +0000

description:
Expand the weak-symbol section to mention module unload issues.  As
noted by martin@ on source-chages-d list.

diffstat:

 doc/TODO.modules |  6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

diffs (17 lines):

diff -r 5ac34eec173b -r e77bcb2e40c3 doc/TODO.modules
--- a/doc/TODO.modules  Fri Dec 28 21:37:56 2018 +0000
+++ b/doc/TODO.modules  Fri Dec 28 21:51:49 2018 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: TODO.modules,v 1.17 2018/12/28 21:37:56 pgoyette Exp $ */
+/* $NetBSD: TODO.modules,v 1.18 2018/12/28 21:51:49 pgoyette Exp $ */
 
 Some notes on the limitations of our current (as of 7.99.35) module
 subsystem.  This list was triggered by an Email exchange between
@@ -208,3 +208,7 @@
     module A, the symbol gets resolved.  But if module A is loaded first,
     the symbol won't be resolved.  If we subsequently load module B, we
     would have to "go back" and re-run the linker for module A.
+
+    Additional difficulties arise when the module which defines the
+    weak symbol gets unloaded.  Then, you would need to re-run the
+    linker and _unresolve_ the weak symbol which is no longer defined.