disable-dependency-tracking issue all of a sudden?

[Ken Cunningham]

Several gnome ports seem to be failing to update with a similar error all of a sudden:

config.status: error: Something went wrong bootstrapping makefile
 fragments
     for automatic dependency tracking.  Try re-running configure with the
     '--disable-dependency-tracking' option to at least be able to build
     the package (albeit without support for automatic dependency
 tracking).

e.g. 
https://lists.macports.org/pipermail/macports-tickets/2018-April/242217.html

and several other ports on my machine at home. At this moment, I'm updating some PPC machines, if that is relevant to this error.

Adding the suggested configure flag "--disable-dependency-tracking" to each Portfile seems to fix them.

Did something change recently?

Ken