[RFC] Enable math functions linking with static library for LTO

[Joseph Myers]

On Thu, 22 Aug 2019, Richard Biener wrote:

> Not sure if that helps answering your question.  In essence,
> this function should tell whether we would emit an UNDEF
> in the end and we want to know that early, at LTO IL generation
> time to communicate this to the linker plugin.  Given previous

To me this sounds like e.g. roundeven and fadd (and, generally, any new 
libm functions we add built-in functions for) *should* be included in the 
list like all the other libm functions, given that on many systems they 
can't be expanded inline for all arguments and so will generate UNDEFs 
(and some people might want to get them from a static library) - even if 
some systems' libm might in fact not have those functions.

-- 
Joseph S. Myers
joseph@codesourcery.com