I got this error while (re)building, using cygwin make.exe version :3.81.
Error : *** target pattern contains no `%\'.
This error is due to a presence of a ":". Therefore it no longer supports windows paths. You need to download version 3.80 and replace the make.exe in the \bin directory.
":"
make.exe
\bin
Apparently it needs cygintl12.dll too.
cygintl12.dll