compatibility fixes for old gcc
compatibility fixes for old gcc

dstoe/vigra,dstoe/vigra,funkey/vigra,dagophil/vigra,dagophil/vigra,dagophil/vigra,funkey/vigra,funkey/vigra,funkey/vigra,dagophil/vigra,dagophil/vigra,dstoe/vigra,funkey/vigra,dstoe/vigra,dstoe/vigra,dstoe/vigra,funkey/vigra,dagophil/vigra,funkey/vigra,dagophil/vigra,dstoe/vigra