This seems to be affecting all builders.
Example: http://buildbot.mongodb.org/builders/Linux%2064-bit/builds/4361/steps/test/logs/stdio
Fri Apr 13 12:53:31 [conn2] test.geo_box1 Assertion failure ok() src/mongo/db/geo/2d.cpp 1509 0x791c51 0xa9c70d 0x9bdc6a 0xac7f32 0xac970b 0x595e27 0xabf213 0xac194f 0x55f366 0xa3a665 0x2aaaaaccd407 0x2aaaab748b0d /mnt/home/buildbot/slave/Linux_64bit/mongo/mongod(_ZN5mongo15printStackTraceERSo+0x21) [0x791c51] /mnt/home/buildbot/slave/Linux_64bit/mongo/mongod(_ZN5mongo8assertedEPKcS1_j+0xfd) [0xa9c70d] /mnt/home/buildbot/slave/Linux_64bit/mongo/mongod(_ZN5mongo9GeoBrowse7currLocEv+0x7a) [0x9bdc6a] /mnt/home/buildbot/slave/Linux_64bit/mongo/mongod(_ZN5mongo12ClientCursor15_recordForYieldENS0_11RecordNeedsE+0x32) [0xac7f32] /mnt/home/buildbot/slave/Linux_64bit/mongo/mongod(_ZN5mongo12ClientCursor14yieldSometimesENS0_11RecordNeedsEPb+0xeb) [0xac970b] /mnt/home/buildbot/slave/Linux_64bit/mongo/mongod(_ZN5mongo14processGetMoreEPKcixRNS_5CurOpEiRb+0x437) [0x595e27] /mnt/home/buildbot/slave/Linux_64bit/mongo/mongod(_ZN5mongo15receivedGetMoreERNS_10DbResponseERNS_7MessageERNS_5CurOpE+0x2b3) [0xabf213] /mnt/home/buildbot/slave/Linux_64bit/mongo/mongod(_ZN5mongo16assembleResponseERNS_7MessageERNS_10DbResponseERKNS_11HostAndPortE+0x71f) [0xac194f] /mnt/home/buildbot/slave/Linux_64bit/mongo/mongod(_ZN5mongo16MyMessageHandler7processERNS_7MessageEPNS_21AbstractMessagingPortEPNS_9LastErrorE+0x76) [0x55f366] /mnt/home/buildbot/slave/Linux_64bit/mongo/mongod(_ZN5mongo3pms9threadRunEPNS_13MessagingPortE+0x295) [0xa3a665] /lib64/libpthread.so.0 [0x2aaaaaccd407] /lib64/libc.so.6(clone+0x6d) [0x2aaaab748b0d]