=> Bootstrap dependency digest>=20010302: found digest-20121220
=> Bootstrap dependency fetch-[0-9]*: found fetch-1.8nb1
=> Checksum SHA1 OK for optipng-0.7.4.tar.gz
=> Checksum RMD160 OK for optipng-0.7.4.tar.gz
===> Installing dependencies for optipng-0.7.4nb1
=> Tool dependency nbpatch-[0-9]*: found nbpatch-20100124
=> Tool dependency checkperms>=1.1: found checkperms-1.11
=> Full dependency zlib>=1.2.3: found zlib-1.2.7
=> Full dependency png>=1.6.0nb1: found png-1.6.2
===> Overriding tools for optipng-0.7.4nb1
===> Extracting for optipng-0.7.4nb1
===> Patching for optipng-0.7.4nb1
=> Applying pkgsrc patches for optipng-0.7.4nb1
===> Creating toolchain wrappers for optipng-0.7.4nb1
===> Configuring for optipng-0.7.4nb1
=> Checking for portability problems in extracted files
Checking for gcc...
Checking for system libpng...
Checking for system zlib...