WARNING: Checksum failure encountered with download of http://downloads.sourceforge.net/numpy/numpy-1.7.0.tar.gz - will attempt other sources if available
WARNING: Renaming /home/dalton/poky/build/downloads/numpy-1.7.0.tar.gz to /home/dalton/poky/build/downloads/numpy-1.7.0.tar.gz_bad-checksum_b2e23b153fad3034ec48336f81eefd33
WARNING: Checksum failure encountered with download of http://downloads.sourceforge.net/swig/swig-3.0.2.tar.gz - will attempt other sources if available
WARNING: Renaming /home/dalton/poky/build/downloads/swig-3.0.2.tar.gz to /home/dalton/poky/build/downloads/swig-3.0.2.tar.gz_bad-checksum_b2e23b153fad3034ec48336f81eefd33
ERROR: Fetcher failure for URL: 'http://downloads.sourceforge.net/swig/swig-3.0.2.tar.gz'. Checksum mismatch!
File: '/home/dalton/poky/build/downloads/swig-3.0.2.tar.gz' has md5 checksum b2e23b153fad3034ec48336f81eefd33 when 62f9b0d010cef36a13a010dc530d0d41 was expected
File: '/home/dalton/poky/build/downloads/swig-3.0.2.tar.gz' has sha256 checksum 4c9af4437123ca1d65498a00b70a7a186972a21f14c8b3cc905b9f5d1705142c when a2669657cabcedc371f63c0457407a183e0b6b2ef4e7e303c1ec9a3964cc7813 was expected
If this change is expected (e.g. you have upgraded to a new version without updating the checksums) then you can use these lines within the recipe:
SRC_URI[md5sum] = "b2e23b153fad3034ec48336f81eefd33"
SRC_URI[sha256sum] = "4c9af4437123ca1d65498a00b70a7a186972a21f14c8b3cc905b9f5d1705142c"
Otherwise you should retry the download and/or check with upstream to determine if the file has become corrupted or otherwise unexpectedly modified.

ERROR: Function failed: Fetcher failure for URL: 'http://downloads.sourceforge.net/swig/swig-3.0.2.tar.gz'. Unable to fetch URL from any source.
ERROR: Logfile of failure stored in: /home/dalton/poky/build/tmp/work/i586-poky-linux/swig/3.0.2-r0/temp/log.do_fetch.19813
ERROR: Task 877 (/home/dalton/poky/meta-openembedded/meta-oe/recipes-devtools/swig/swig_3.0.2.bb, do_fetch) failed with exit code '1'