Hi,

While playing with the arithmetic libraries FPU and FP, I think I stumbled upon a bug in FPU arithmetic library which seems to be related to an interaction between FPU library and shadings.

It is illustrated in the minimal example below (this is with a recent CVS version under win XP) :

 

%###############################

\makeatletter\let\ifGm <at> compatii\relax\makeatother

\documentclass{beamer}

\usepackage{tikz}

%\usepackage{fp}
%\usetikzlibrary{fixedpointarithmetic}
%\pgfkeys{/pgf/fixed point arithmetic}
%\pgfkeys{/pgf/number format/.cd , fixed, precision=3}

\usetikzlibrary{fpu}
\pgfkeys{/pgf/fpu, /pgf/fpu/output format=fixed}

\begin{document}

\begin{frame}
\begin{tikzpicture}

\fill [top color = blue, bottom color=white] (0,0) rectangle (1,0.5);
%%% The above line gives the error message below with FPU library. There is no issue with FP.

\fill  (0,0) rectangle (1,0.5);  %%%        No problem with this rectangle without shading

\end{tikzpicture}
\end{frame}

\end{document}

%################################################
 

! Package PGF Math Error: Sorry, an internal routine of the floating point unit
 got an ill-formatted floating point number `0.0'. The unreadable part was near
 '0.0'..

See the PGF Math package documentation for explanation.
Type  H <return>  for immediate help.