[Issue 14959] New: Regression in HEAD: linker error on printing SysTime with writeln

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=14959

          Issue ID: 14959
           Summary: Regression in HEAD: linker error on printing SysTime
                    with writeln
           Product: D
           Version: D2
          Hardware: x86
                OS: Mac OS X
            Status: NEW
          Severity: regression
          Priority: P1
         Component: dmd
          Assignee: nobody at puremagic.com
          Reporter: jack at jackstouffer.com

This works in DMD 2.068, but errors in git head of master

import std.stdio : written;
import std.datetime;

void main() {
    auto d1 = Clock.currTime;
    writeln(d2);
}

--------------------------
$ dmd test.d

Undefined symbols for architecture x86_64:
 
"_D3std6format64__T14formatIntegralTS3std5array17__T8AppenderTAyaZ8AppenderTmTaZ14formatIntegralFNaNbNfS3std5array17__T8AppenderTAyaZ8AppenderxmKxS3std6format18__T10FormatSpecTaZ10FormatSpeckmZv",
referenced from:
     
_D3std6format61__T11formatValueTS3std5array17__T8AppenderTAyaZ8AppenderThTaZ11formatValueFNaNfS3std5array17__T8AppenderTAyaZ8AppenderhKS3std6format18__T10FormatSpecTaZ10FormatSpecZv
in test.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
--- errorlevel 1

--