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digitalmars.D.bugs - [Issue 846] New: Error 42: Symbol Undefined _D1a7__arrayZ

reply d-bugmail puremagic.com writes:

           Summary: Error 42: Symbol Undefined _D1a7__arrayZ
           Product: D
           Version: 0.177
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: sean f4.ca

This is a variation of the "template library bug," similar to why std.boxer is
incompatible with debug user apps.  Support for in/out contracts seems to be
fixed, as they always seem to be generated within the template function body,
but it appears that array bounds and assertion checks are still sometimes
expected to exist in the object containing the declaration of the template
code.  Here is an example:

    module a;

    template ElemTypeOf( T )
        alias typeof(T[0]) ElemTypeOf;

    template removeIf_( Elem, Pred )
        size_t fn( Elem[] buf, Pred pred )
            void exch( size_t p1, size_t p2 )
                Elem t  = buf[p1];
                buf[p1] = buf[p2];
                buf[p2] = t;

            size_t cnt = 0;

            for( size_t pos = 0, len = buf.length; pos < len; ++pos )
                if( pred( buf[pos] ) )
                    exch( pos, pos - cnt );
            return buf.length - cnt;

    template removeIf( Buf, Pred )
        size_t removeIf( Buf buf, Pred pred )
            return removeIf_!(ElemTypeOf!(Buf), Pred).fn( buf, pred );


    import a;

    void main()
        auto num = removeIf( "abcdef".dup, ( char c ) { return c == 'c'; } );

C:\code\src\d\test>dmd b
c:\bin\dmd\bin\..\..\dm\bin\link.exe b,,,user32+kernel32/noi;
OPTLINK (R) for Win32  Release 7.50B1
Copyright (C) Digital Mars 1989 - 2001  All Rights Reserved

 Error 42: Symbol Undefined _D1a7__arrayZ
--- errorlevel 1

It appears that whether this error occurs may somehow be related to the
inlining mechanism, because I have some template functions that exhibit this
behavior and others that do not.  This bug is a major obstacle to building
libraries containing template code in D, particularly when the user cannot
manually link a debug library because the library name is selected
automatically (as with phobos.lib).  Also, I don't entirely understand why a
separate bound-check and assert function must apparently be generated for every
module, since the contents should be immutable.  The easiest fix for std.boxer
(if perhaps not user libraries) would be to link separate standard libraries
for debug and release builds--phobos.lib vs. phobosd.lib, for example.  But it
would be far preferable if code generation could be fixed such that this
problem no longer occurs.

Jan 13 2007
next sibling parent d-bugmail puremagic.com writes:

------- Comment #1 from sean f4.ca  2007-01-23 13:09 -------
This is related to issue 8.

Jan 23 2007
prev sibling next sibling parent reply d-bugmail puremagic.com writes:

------- Comment #2 from bugzilla digitalmars.com  2007-01-31 03:41 -------
The problem is that the __array() function is not generated for module a if it
is compiled with -release. I'll fix it so it does, but to get the example to
work, you'll still need to link with a.obj.

Jan 31 2007
parent Sean Kelly <sean f4.ca> writes:
d-bugmail puremagic.com wrote:
 The problem is that the __array() function is not generated for module a if it
 is compiled with -release. I'll fix it so it does, but to get the example to
 work, you'll still need to link with a.obj.

That's fine. My only concern is that template code in release libraries be usable in debug applications (since non-template code is). The only remaining issues seem to be _array() and _assert() (and possibly not _assert()--I haven't found a case where this breaks yet), and always building it/them into the module should address this.
Jan 31 2007
prev sibling parent d-bugmail puremagic.com writes:

ultimate.macfan.atic gmail.com changed:

           What    |Removed                     |Added
                 CC|                            |ultimate.macfan.atic gmail.c
                   |                            |om
             Status|RESOLVED                    |REOPENED
           Keywords|                            |link-failure
         Resolution|FIXED                       |
            Summary|Error 42: Symbol Undefined  |Error 42: Symbol Undefined
                   |_D1a7__arrayZ               |"<mangle_of_class_template>_
                   |                            |_arrayZ"
            Version|0.177                       |2.014

------- Comment #5 from ultimate.macfan.atic gmail.com  2008-11-03 04:40 -------
I'm getting linking errors when I compile and link a module I wrote using dmd
that sound similar to what's described here.  I've looked for other
documentation of this issue, but I haven't found any so I'm going to go ahead
and post this as a bug to see if anyone else can replicate it, even though this
problem appears to have been fixed the last time it was rearing its (insert
creative adjective here) head.

The error output:

C:\Documents and Settings\Christopher Johnson\My Documents>dmd -v
parse     boggle
semantic  boggle
import    object        (\dmd\src\phobos\object.d)
import    std.c.stdlib  (\dmd\src\phobos\std\c\stdlib.d)
import    std.c.stddef  (\dmd\src\phobos\std\c\stddef.d)
import    std.ctype     (\dmd\src\phobos\std\ctype.d)
import    edu.utah.eng.chjohnso.set     (edu\utah\eng\chjohnso\set.d)
import    std.stdio     (\dmd\src\phobos\std\stdio.d)
import    std.c.stdio   (\dmd\src\phobos\std\c\stdio.d)
import    std.c.stdarg  (\dmd\src\phobos\std\c\stdarg.d)
import    std.format    (\dmd\src\phobos\std\format.d)
import    std.stdarg    (\dmd\src\phobos\std\stdarg.d)
import    std.utf       (\dmd\src\phobos\std\utf.d)
import    std.contracts (\dmd\src\phobos\std\contracts.d)
import    std.conv      (\dmd\src\phobos\std\conv.d)
import    std.string    (\dmd\src\phobos\std\string.d)
import    std.algorithm (\dmd\src\phobos\std\algorithm.d)
import    std.math      (\dmd\src\phobos\std\math.d)
import    std.c.math    (\dmd\src\phobos\std\c\math.d)
import    std.traits    (\dmd\src\phobos\std\traits.d)
import    std.typetuple (\dmd\src\phobos\std\typetuple.d)
import    std.date      (\dmd\src\phobos\std\date.d)
import    std.dateparse (\dmd\src\phobos\std\dateparse.d)
import    std.c.windows.windows (\dmd\src\phobos\std\c\windows\windows.d)
import    std.functional        (\dmd\src\phobos\std\functional.d)
import    std.typecons  (\dmd\src\phobos\std\typecons.d)
import    std.metastrings       (\dmd\src\phobos\std\metastrings.d)
import    std.iterator  (\dmd\src\phobos\std\iterator.d)
import    std.c.string  (\dmd\src\phobos\std\c\string.d)
import    std.encoding  (\dmd\src\phobos\std\encoding.d)
import    std.uni       (\dmd\src\phobos\std\uni.d)
import    std.array     (\dmd\src\phobos\std\array.d)
import    std.system    (\dmd\src\phobos\std\system.d)
import    std.bitmanip  (\dmd\src\phobos\std\bitmanip.d)
import    std.intrinsic (\dmd\src\phobos\std\intrinsic.d)
import    std.gc        (\dmd\src\phobos\std\gc.d)
import    gcstats       (\dmd\src\phobos\gcstats.d)
import    std.file      (\dmd\src\phobos\std\file.d)
import    std.path      (\dmd\src\phobos\std\path.d)
import    std.regexp    (\dmd\src\phobos\std\regexp.d)
import    std.outbuffer (\dmd\src\phobos\std\outbuffer.d)
import    std.windows.syserror  (\dmd\src\phobos\std\windows\syserror.d)
import    std.windows.charset   (\dmd\src\phobos\std\windows\charset.d)
semantic2 boggle
semantic3 boggle
code      boggle
function  this
function  chooseChar
function  randomize
function  getFace
function  playWord
function  getScore
function  __foreachbody21
function  _makeSetConditionary
function  __foreachbody22
function  allLegalWordsPlayed
function  __dgliteral1
function  allSharedLegalWordsPlayed
function  __dgliteral2
function  allIllegalWordsPlayed
function  __dgliteral3
function  scoreByLength
function  isLegal
function  verify
function  this
function  empty
function  length
function  insert
function  erase
function  clear
function  swap
function  opIn_r
function  opApply
function  main
\dm\bin\link.exe boggle,,,user32+kernel32/noi;
OPTLINK (R) for Win32  Release 8.00.1
Copyright (C) Digital Mars 1989-2004  All rights reserved.
 Error 42: Symbol Undefined _D3edu4utah3eng8chjohnso3set7__arrayZ
--- errorlevel 1

This link failure persists when I add the "-debug" switch, but goes away if I
add the "-release" switch.  So thankfully in the meantime there is some kind of
work-around so I can at least get my code to *run*, but not being able to
compile with -debug or without the extra baggage of -release sounds like it's
an issue that could use some improvement both for saving keystrokes at the
command-line as well as for optimal debugging.

Hope I'm doing this in proper procedure!  :-)

Should my email not make it into this otherwise, it's
ultimate.mac.fanatic gmail.com  (and your Mac Fanatic only compiles D on
windows because he can't get any D 2.0 compilers for his Mac OS X 10.5  :-P).

Nov 03 2008