Hi Andres, Thanks for the reply! Note that I get this message even running 'cabal install' a second time after changing nothing. Is that scenario an example of what you mean by a "potentially dangerous cabal invocation"? I've been unable to avoid this error message by any other means that (a) 'ghc-pkg unregister <package>' or (b) '--force-reinstall'. So far, '--solver=modular' hasn't helped. So I'm hoping for something less aggressive. In particular, in case nothing has changed, I want 'cabal install' to succeed (exit code 0) so that my automated build & install & release processes will continue rather than get stopped. Regards, - Conal On Sat, Feb 4, 2012 at 9:51 PM, Andres Löh <andres.loeh@googlemail.com>wrote:
Hi Conal.
On Sun, Feb 5, 2012 at 12:36 AM, Conal Elliott <conal@conal.net> wrote:
Since upgrading to 7.4.1, if I 'cabal install' successfully and then 'cabal install' a second time without first doing a 'ghc-pkg unregister <package-name>', I get the following complaint:
[...]
The warning is intended to prevent you from breaking your system without knowing that you know that you're running a potentially dangerous cabal invocation.
The --force-reinstalls flag should always make it build. If it doesn't, it's a bug.
In addition, I'm planning to make the warning a little bit less aggressive before the release.
The only path I've found so far that's willing to rebuild or even say nothing needs rebuilding (when nothing does) is to 'ghc-pkg unregister' and then 'cabal install' again. I'm getting the same behavior on Red Hat 5 and Mac OS 10.6.8, both compiled from sources.
I'd be surprised if the OS matters. But as I said, I've not yet encountered a situation where it wouldn't build given --force-reinstalls.
Cheers, Andres