I'm afraid I'm not clear on the semantics of builtin_with_linkage_p (as in the current checked-in version). It says:
/* Return true if the builtin DECL is implemented in a standard library. Otherwise returns false which doesn't guarantee it is not (thus the list of handled builtins below may be incomplete). */ But what does "is implemented in a standard library" mean? Certainly plenty of GCC ports are for systems that e.g. don't have fmaf64 which is included in that switch statement, and calls to fmaf64 on such systems will result in an undefined reference unless it's on an architecture where GCC can expand that inline. Specifically: does Tejas's roundeven patch (and likewise the fadd patch) need updating to add those functions to the switch statement in builtin_with_linkage_p? What are the correct semantics for a built-in function with the following properties: it may not be in the system libc / libm on all systems, but GCC can't always expand it inline either, so it may result in an undefined reference on systems where it's not in system libc / libm? If it's only meant to be for functions you *know* are in a standard library on the system used, I'd expect checks of the libc_has_function target hook. If, however, it's meant to be for functions that might result in an undefined reference (where GCC expects there to be a library function to satisfy that reference, but some systems don't have that function), I'd expect it to be based on whether a library name was passed when add_builtin_function was called, if that's something you can determine by examining the DECL - and in that case I wouldn't expect there to be a long switch statement listing particular functions, because the relevant information is specified when the built-in functions are created in the first place. -- Joseph S. Myers jos...@codesourcery.com
