http://d.puremagic.com/issues/show_bug.cgi?id=7720

           Summary: asm silent wrong code generation
           Product: D
           Version: D2
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: nobody@puremagic.com
        ReportedBy: deadalnix@gmail.com


--- Comment #0 from deadalnix <deadalnix@gmail.com> 2012-03-17 12:56:07 PDT ---
See code blow :

static uint globalThreadLocal = 123456;

uint foo() {
    asm {
        naked;
        mov EAX, globalThreadLocal;
        ret;
    }
}

void main() {
    uint x = foo();

    import std.stdio;
    writeln(x);
}

Output garbage. This code should generate an error and not compile as if it was correct.

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yebblies <yebblies@gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |yebblies@gmail.com


--- Comment #1 from yebblies <yebblies@gmail.com> 2012-03-18 11:21:41 EST ---
It's not that simple.  IIRC "mov EAX, globalThreadLocal" moves the offset of globalThreadLocal into EAX.  While this obviously isn't what you expected, this is valid and useful.  How else would you get the offset?

After all, you're using the inline assembler.  The compiler will never be able to protect you against writing incorrect assembly.

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--- Comment #2 from deadalnix <deadalnix@gmail.com> 2012-03-18 06:04:39 PDT ---
(In reply to comment #1)
> It's not that simple.  IIRC "mov EAX, globalThreadLocal" moves the offset of globalThreadLocal into EAX.  While this obviously isn't what you expected, this is valid and useful.  How else would you get the offset?
> 
> After all, you're using the inline assembler.  The compiler will never be able to protect you against writing incorrect assembly.

In this case, this behavior should be documented.

But this is confusing, because it is not what happen with other variables (variable value is copied into the register).

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