https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108763
--- Comment #2 from Steven Schveighoffer <schveiguy at gmail dot com> --- (In reply to Andrew Pinski from comment #1) > https://github.com/dlang/dmd/blob/master/druntime/src/core/vararg.d > > version (GNU) { /* TypeInfo-based va_arg overload unsupported */ } > > ... oof. This is somewhat of a problem, because the undead package (https://github.com/dlang/undead) uses it inside doformat, and this means that anyone wanting to use those packages cannot do so with GDC. The undead package is a collection of modules that are no longer in mainline D, and so the point is to be able to use older modules with older code. If this is deemed to be unsupportable, then people will just have to live with not being able to use GDC for programs using that package. I also can look at possibly disabling the offending code for GDC users, and then people can use the other parts of undead (e.g. undead.xml) Thanks for pointing that out!