Changed the handling of variadic intrinsics a bit. Removed the -fp80 option and made real be 80bit floats on X86, this is what the D spec really says it should be and fixes a bunch of issues. Changed the handling of parameter attributes to a bit more generalized approach. Added sext/zext attributes for byte/short/ubyte/ushort parameters, fixes #60 . Parameter attribs now properly set for intrinsic calls if necessary. Made the tango.math.Math patch less intrusive. Fixed/added some mini tests.

module bug1;
struct Foo { Foo opSub(ref Foo b) { return Foo(); } }
struct Bar { Foo whee; }
void test(ref Bar moo) { Foo nngh; auto plonk = nngh - moo.whee; }
void main() { Bar bar; test(bar); }