some working example code:
$ dmd --version
DMD64 D Compiler v2.072.2
Copyright (c) 1999-2016 by Digital Mars written by Walter Bright
$ dmd degenerate.d
Undefined symbols for architecture x86_64:
"_D3std6format18__T10FormatSpecTaZ10FormatSpec6fillUpMFNaZv", referenced from:
_D3std6format18__T10FormatSpecTaZ10FormatSpec63__T17writeUpToNextSpecTS3std5array17__T8AppenderTAyaZ8AppenderZ17writeUpToNextSpecMFNaS3std5array17__T8AppenderTAyaZ8AppenderZb in degenerate.o
_D3std6format18__T10FormatSpecTaZ10FormatSpec59__T17writeUpToNextSpecTS3std5stdio4File17LockingTextWriterZ17writeUpToNextSpecMFS3std5stdio4File17LockingTextWriterZb in degenerate.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Error: linker exited with status 1
-----------------<degenerate.d>------------------
import std.stdio;
void main(){
writeln(["string1", "string2"]);
}
-------------------------------------------------
a more realistic example which causes the same error:
-----------------<realistic.d>-------------------
import std.stdio; // for writeln
import std.algorithm; // for map
import std.conv; // for to!string
import std.range; // for iota
string[] substrings(string n) {
// returns a "sliding window" array of substrings of n
return iota(1,8).map!(i => n[i..(i+3)]).array;
}
void main(){
int[] n = [0,1,2,3,4,5,6,7,8,9];
writeln(n.map!(to!string).join.substrings); // <------------ this line causes the error
writeln(n.map!(to!string).join.substrings.join(",")); // <-- this would be the fix
}
-------------------------------------------------
i think this is a regression because this error was not happening before i updated dmd to v2.072.2.
Comment #1 by naclypi — 2017-01-22T06:14:57Z
issue 16661 - https://issues.dlang.org/show_bug.cgi?id=16661 - seemed to have the same error but in a different form. it was the only issue i found that had a similar error message after searching around for a bit