buildbot exception in MacPorts on ports-10.7_x86_64_legacy-builder

[buildbot at macports.org]

The Buildbot has detected a build exception on builder ports-10.7_x86_64_legacy-builder while building macports/macports-ports. Full details are available at:
    https://build.macports.org/builders/ports-10.7_x86_64_legacy-builder/builds/28190

Buildbot URL: https://build.macports.org/

Buildslave for this Build: ports-10.7_x86_64_legacy

Build Reason: The Triggerable scheduler named 'ports-10.7_x86_64_legacy-trigger' triggered this build
Build Source Stamp: [branch master] 6a1ca557a195e3989aff6631556cc9f003281828
Blamelist: Leo Singer <leo.singer at ligo.org>

BUILD FAILED: exception interrupted

Sincerely,
 -The Buildbot