------- Comment #1 from joseph at codesourcery dot com 2005-10-29 20:09 ------- Subject: Re: New: Complex arithmetic on special cases is incorrect.
On Sat, 29 Oct 2005, kargl at gcc dot gnu dot org wrote: > * underflow, sign and efficiency bugs by rewriting I*y as > * (0.0+I)*(y+0.0*I) and laboriously computing the full complex product. Note that the correct form is (0.0+I)*y, since I is (per C99+TC1+TC2) _Complex_I, of complex type (Annex G imaginary types conflicting with the normative standard, unless and until anything changes in this respect following DR#323). But the usual arithmetic conversions as specified in the standard do not convert both operands to complex, so one can be real and one complex. I suspect there are lots of presumptions in the compiler that arithmetic operations such as PLUS_EXPR and MULT_EXPR have both operands of the same type, which would need to be fixed to represent a real*complex product properly. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24581
