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digitalmars.D.bugs - [Bug 151] New: Pragma without ';' results in undefined symbols

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/bugzilla/show_bug.cgi?id=151

           Summary: Pragma without ';' results in undefined symbols
           Product: D
           Version: 0.157
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: lio lunesu.com



type main.d


import std.stdio;//needs at least 1 import
pragma(lib,"ws2_32.lib")//;
class bla{}
void main(){}


dmd main.d


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

main.obj(main)
 Error 42: Symbol Undefined __Class_4main3bla
--- errorlevel 1


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May 23 2006
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/bugzilla/show_bug.cgi?id=151


smjg iname.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |smjg iname.com





If the semicolon is omitted, then the pragma modifies the declaration or
statement that immediately follows it, in this case the class bla.

But it would appear from the spec that pragma(lib) is valid only on its own. 
It is indeed absurd that it behaves as it does, but in reality (AIUI) it
shouldn't compile at all.


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May 24 2006
prev sibling next sibling parent reply Thomas Kuehne <thomas-dloop kuehne.cn> writes:
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d-bugmail puremagic.com schrieb am 2006-05-23:

 http://d.puremagic.com/bugzilla/show_bug.cgi?id=151

type main.d


 import std.stdio;//needs at least 1 import
 pragma(lib,"ws2_32.lib")//;
 class bla{}
 void main(){}


dmd main.d


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

 main.obj(main)
  Error 42: Symbol Undefined __Class_4main3bla
 --- errorlevel 1


While
"pragma(lib, "ws2_32.lib") class Blah{}" [A]
is clearly illegal,
"pragma(lib, "ws2_32.lib") class Blah{};" [B]
is legal but buggy.

http://www.dstress.com/d/pragma.html :

 pragma(ident) declaration; // influence one declaration


Thus [B] should provide the symbols of ws2_32.lib only to the Blah
class. I'd opt to state that "lib" and "msg" influence neither
declarations nor statements, thus prohibiting:

pragma(msg, "123") statement;
pragma(msg, "123") declaration;
pragma(msg, "123") { statement } 
pragma(msg, "123") { declaration }
pragma(msg, "123"): declaration;

pragma(lib, "123") statement;
pragma(lib, "123") declaration;
pragma(lib, "123") { statement } 
pragma(lib, "123") { declaration }
pragma(lib, "123"): declaration;

Added to DStress as
http://dstress.kuehne.cn/nocompile/p/pragma_07_A.d

Thomas

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May 24 2006
parent reply "Chris Miller" <chris dprogramming.com> writes:
On Wed, 24 May 2006 12:31:15 -0400, Thomas Kuehne <thomas-dloop kuehne.cn>  
wrote:


 While
 "pragma(lib, "ws2_32.lib") class Blah{}" [A]
 is clearly illegal,
 "pragma(lib, "ws2_32.lib") class Blah{};" [B]
 is legal but buggy.

 http://www.dstress.com/d/pragma.html :

 pragma(ident) declaration; // influence one declaration




Doesn't seem right, notice:

pragma(ident)   // influence block of declarations
{   declaration;
     declaration;
}

doesn't have ";" after the block. Anyway, the way you say wouldn't be  
consistent with other things, like "extern(C) void foo() {}" doesn't need  
";" after. Plus, would that extra ";" have any significance? seems like it  
would only require extra work in the compiler to enforce. I think  
"pragma(ident) declaration; // influence one declaration" should not  
include the ";" and it was only typed in there by habit and/or to look  
like valid code.
May 24 2006
parent Stewart Gordon <smjg_1998 yahoo.com> writes:
Chris Miller wrote:

 On Wed, 24 May 2006 12:31:15 -0400, Thomas Kuehne 
 <thomas-dloop kuehne.cn> wrote:
 

 While
 "pragma(lib, "ws2_32.lib") class Blah{}" [A]
 is clearly illegal,
 "pragma(lib, "ws2_32.lib") class Blah{};" [B]
 is legal but buggy.
 
 http://www.dstress.com/d/pragma.html :

 pragma(ident) declaration; // influence one declaration




 
 Doesn't seem right, notice:
 
 pragma(ident)   // influence block of declarations
 {   declaration;
     declaration;
 }


Yes, that bit of the spec is rather loose.  It seems it was intended to 
illustrate, rather than to specify, with the semicolons there merely to 
make them look like those declarations that happen to end with one.


 doesn't have ";" after the block. Anyway, the way you say wouldn't be 
 consistent with other things, like "extern(C) void foo() {}" doesn't 
 need ";" after. Plus, would that extra ";" have any significance?


<snip>

The syntax for pragmas is incomplete in the spec.  But the trailing ";" 
in Thomas's snippet is separate from both the class definition and the 
pragma.  It's a null DeclDef, allowed by the spec only at module level. 
  It appears that the point is to lighten the load for people coming 
from C(++), where a semicolon is required after a struct, union, class 
or enum definition.

Stewart.
May 30 2006
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/bugzilla/show_bug.cgi?id=151


bugzilla digitalmars.com changed:

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





Fixed 0.158


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May 25 2006