Fix more warnings and bugs if DFP/I128 disabled, patch by LRN

git-svn-id: https://svn.code.sf.net/p/mingw-w64/code@6355 4407c894-4637-0410-b4f5-ada5f102cad1
merge from experimental

git-svn-id: https://svn.code.sf.net/p/mingw-w64/code@6356 4407c894-4637-0410-b4f5-ada5f102cad1
add new project

git-svn-id: https://svn.code.sf.net/p/mingw-w64/code@6357 4407c894-4637-0410-b4f5-ada5f102cad1