[Rd] Standalone Mathlib, C++ and ISNAN()

Bill Northcott w.northcott at unsw.edu.au
Sun Jan 9 01:09:18 CET 2005

On 09/01/2005, at 9:11 AM, Thomas Lumley wrote:
> The C++ math header undefines isnan, so if isnan is a macro, ISNAN() 
> will not work in C++ code.
> C99 specifies that isnan is a macro, but in C90 compilers, where it is 
> an extension, isnan is often a function (explaining why the issue 
> didn't come up earlier). For example, isnan is a macro on my Mac 
> laptop but a function on my Linux desktop.
> R-devel now defines ISNAN to call a function if used in C++ code. It 
> still calls isnan in C code.

Many thanks for that.

Does this mean the changes will be in the current daily builds?
I presume the function involved is now in the standalone Rmath build.

Bill Northcott

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