= Recurrent Problems on Leopard =

== poll() doesn't work ==
see #13259.

== environment variables become blank between configure and build phases ==
This manifests as error messages like: `unable to execute -DNDEBUG: No such file or directory`. ($CC is an empty string, so what was meant to be the the first argument to the compiler is now the first thing on the command line, and is treated as a command name by the shell.) Seems to frequently occur when building Python modules; see #13930.

This problem can be worked around by cleaning the work area of the affected port (`sudo port clean --work foo`) and then running the `port install` (or `port upgrade`) command again.

Here is [http://lists.macosforge.org/pipermail/macports-users/2008-April/009991.html an analysis of the problem] by Bryan Blackburn.

With r36719 and r36722 this should be fixed on trunk, but the fix hasn't yet made it to the 1.6 release.

== `ld: cycle in dylib re-exports with /usr/X11/lib/libGL.dylib` ==
This is the result of a misfeature in Leopard's linker. See Apple's Technical Q&A on the subject [http://developer.apple.com/qa/qa2007/qa1567.html here]. It can generally be fixed by adding the following to the portfile inside a `platform darwin 9` block:
{{{
configure.ldflags-append 	-dylib_file \
			/System/Library/Frameworks/OpenGL.framework/Versions/A/Libraries/libGL.dylib:\
			/System/Library/Frameworks/OpenGL.framework/Versions/A/Libraries/libGL.dylib
}}}