http://d.puremagic.com/issues/show_bug.cgi?id=532

           Summary: Wrong name mangling for template alias params of local
                    vars
           Product: D
           Version: 0.174
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla@digitalmars.com
        ReportedBy: clugdbug@yahoo.com.au


In this example, in moo!(A), the value of Mang!(A).mangledname depends on whether it is inside a 'static assert' or not. This seems to be a symptom of a more general problem: I've seen many similar effects, but this is the simplest so far.

---------
template Mang(alias F)
{
    class G { }
    alias void function (G ) H;
    const char [] mangledname = typeof(H).mangleof;
}

template moo(alias A)
{
    const char [] a = Mang!(A).mangledname;
    static assert(Mang!(A).mangledname == a); // FAILS !!!
}

void main()
{
    int q;
    char [] b = moo!(q).a;
}


-- 

d-bugmail@puremagic.com schrieb am 2006-11-16:
> http://d.puremagic.com/issues/show_bug.cgi?id=532

> In this example, in moo!(A), the value of Mang!(A).mangledname depends on whether it is inside a 'static assert' or not. This seems to be a symptom of a more general problem: I've seen many similar effects, but this is the simplest so far.
>
> ---------
> template Mang(alias F)
> {
>     class G { }
>     alias void function (G ) H;
>     const char [] mangledname = typeof(H).mangleof;
> }
>
> template moo(alias A)
> {
>     const char [] a = Mang!(A).mangledname;
>     static assert(Mang!(A).mangledname == a); // FAILS !!!
> }
>
> void main()
> {
>     int q;
>     char [] b = moo!(q).a;
> }

Added to DStress as http://dstress.kuehne.cn/compile/m/mangleof_19_A.d http://dstress.kuehne.cn/compile/m/mangleof_19_B.d http://dstress.kuehne.cn/compile/m/mangleof_19_C.d http://dstress.kuehne.cn/compile/m/mangleof_19_D.d http://dstress.kuehne.cn/compile/m/mangleof_19_E.d http://dstress.kuehne.cn/compile/m/mangleof_19_F.d http://dstress.kuehne.cn/compile/m/mangleof_19_G.d

Thomas

http://d.puremagic.com/issues/show_bug.cgi?id=532


clugdbug@yahoo.com.au changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|0.174                       |0.178




------- Comment #2 from clugdbug@yahoo.com.au  2007-01-03 05:42 -------
(In reply to comment #0)
> template Mang(alias F)
> {
>     class G { }
>     alias void function (G ) H;
>     const char [] mangledname = typeof(H).mangleof;
> }
> 
> template moo(alias A)
> {
>     const char [] a = Mang!(A).mangledname;
>     static assert(Mang!(A).mangledname == a); // FAILS !!!
> }
> 
> void main()
> {
>     int q;
>     char [] b = moo!(q).a;
> }

Some more information....

Inside the static assert, the type is:
void function ( Mang!(bug.main().q).G );

PFC3bug29__T4MangS17_D3bug4mainFZv1qiZ1GZv

but outside the static assert, it is:
void function ( main.moo(bug.main().q)).Mang!(bug.main().q).G );

PFCmain28__T3mooS17_D3bug4mainFZv1qiZ29__T4MangS17_D3bug4mainFZv1qiZ1GZv

The problem is that in this second case, the mangled name of the calling function gets appended to the start of the fully qualified name. I can't see why this would be necessary ('q' is already fully qualified in the alias parameter, so it cannot conflict with anything else).

A secondary problem is that in the second case, extern (C),(Windows), (Pascal)
symbols such 'main' are not mangled correctly with the new scheme from D0.176:
it doesn't have the length information included.
main.moo!(...)   is Cmain28__T3moo...
but it should be    C4main28_T3moo...
This applies to any extern(C), (Windows), or (Pascal) function, not just
"main",
but doesn't apply to normal D functions.

It is still a problem with D1.0.

All other name mangling bugs I've reported since D0.176 seem to be consequences of this one. The mangling used inside the static assert seems natural, and I think it should be used in the other case as well, unless there's a known problem with it.


-- 

http://d.puremagic.com/issues/show_bug.cgi?id=532


clugdbug@yahoo.com.au changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |critical




------- Comment #3 from clugdbug@yahoo.com.au  2007-01-24 06:31 -------
Changing status to critical because I've seen bad code generation in library code as a result of this bug. There seems to be a fundamental instability in the compiler at this point, almost as though there's an uninitialised variable.

This issue is a blocker for my meta.NameOf code.


-- 

http://d.puremagic.com/issues/show_bug.cgi?id=532


davidl@126.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P2                          |P1
            Version|0.178                       |1.005




------- Comment #4 from davidl@126.com  2007-02-12 19:49 -------
i change d's version of this bug. and priority to 1 , hope walter could fix this bug sooner.


-- 

http://d.puremagic.com/issues/show_bug.cgi?id=532


tknott@gmail.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|1.005                       |0.178




------- Comment #5 from tknott@gmail.com  2007-02-12 22:56 -------
(In reply to comment #4)
> i change d's version of this bug. and priority to 1 , hope walter could fix this bug sooner.
> 

Please do not change the version number for bug reports.  See D.bugs/10071 (http://www.digitalmars.com/webnews/newsgroups.php?search_txt=&group=digitalmars.D.bugs&article_id=10071)


-- 

http://d.puremagic.com/issues/show_bug.cgi?id=532


clugdbug@yahoo.com.au changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED




------- Comment #6 from clugdbug@yahoo.com.au  2007-04-13 20:10 -------
Fixed DMD 1.012.


--