Comment #0 by bearophile_hugs — 2011-05-07T16:12:45Z
This D2 code:
import std.stdio;
void main() {
string[char] tab = ['e': "red", 'b': "blue"];
string r;
foreach (c; "aba") {
// if (c in tab) r ~= tab[c]; // OK
r ~= tab.get(c, ""); // ERR
}
writeln(r);
}
Gives me a linker error (DMD 2.053beta):
test.obj(test)
Error 42: Symbol Undefined _D6object28__T16AssociativeArrayTaTAyaZ16AssociativeArray3getMFaLAyaZAya
Comment #1 by kennytm — 2011-05-08T00:19:05Z
Reproducible on Mac OS X. The missing symbol demangled is
immutable(char)[] object.AssociativeArray!(char, immutable(char)[]).AssociativeArray.get(char, lazy immutable(char)[])
It is probably a regression since I can't reproduce it on ideone which uses 2.042, but it may simply be that the error doesn't manifest on Linux.
Reduced test case:
--------------------------
import std.stdio; // <-- the import is necessary to trigger the bug!
void main() {
string[char] tab; // <-- must be a string[char]?
tab.get('c', "");
}
--------------------------
Undefined symbols:
"_D6object28__T16AssociativeArrayTaTAyaZ16AssociativeArray3getMFaLAyaZAya", referenced from:
__Dmain in x.o
ld: symbol(s) not found
collect2: ld returned 1 exit status
--- errorlevel 1
--------------------------
Comment #2 by r.sagitario — 2011-06-18T09:31:05Z
This seems to happen when there is an identical associative array declared in an imported file, but that is not used to generate code from. Obviously dmd believes it does not need to generate the template code again. Here's a reduced test case:
-----
module test1;
int[string] map;
-----
module test2;
import test1;
int main()
{
int[string] m;
return m.keys.length;
}
-----
compiling this with "dmd test2.d" with the latest compiler from github yields
OPTLINK (R) for Win32 Release 8.00.11
Copyright (C) Digital Mars 1989-2010 All rights reserved.
http://www.digitalmars.com/ctg/optlink.html
test2.obj(test2)
Error 42: Symbol Undefined _D6object28__T16AssociativeArrayTAyaTiZ16Associative
Array4keysMFNdZAAya
--- errorlevel 1