import std.stdio; static import core.math; void main() { writeln(core.math.rndtonl(9.0)); } It seems like this is a DMC only function.
Commits pushed to master at https://github.com/dlang/phobos https://github.com/dlang/phobos/commit/b4f675fe150afaa577d6a41d6013ca33d932bd57 Work On Issue 18693 - Remove rndtonl from std.math https://github.com/dlang/phobos/commit/813327d51affb1af8cdd1c7651612e8778109f10 Merge pull request #6429 from JackStouffer/issue18693 Work On Issue 18693 - Remove rndtonl from std.math merged-on-behalf-of: Jack Stouffer <jack@jackstouffer.com>