Address of Labels (Msvc)

Address of labels (MSVC)

The only way of doing this in MSVC is by using inline assembly (which basically buggers you for x64):

int _tmain(int argc, _TCHAR* argv[])
{
case_1:
    void* p;
    __asm{ mov [p],offset case_1 }
    printf("0x%p\n",p);
    return 0;
}

If you plan on doing something like this, then the best way would be to write the whole interpreter in assembly then link that in to the main binary via the linker (this is what LuaJIT did, and it is the main reason the VM is so blindingly fast, when its not running JIT'ed code that is).

LuaJIT is open-source, so you might pick up some tips from it if you go that route. Alternatively you might want to look into the source of forth (whose creator developed the principle you're trying to use), if there is an MSVC build you can see how they accomplished it, else you're stuck with GCC (which isn't a bad thing, it works on all major platforms).

labels as values in clang

The examples you build should work, I've just verified it using Apple LLVM version 7.0.2 (clang-700.1.81).

The mentioned bug reports seem to report this very same issue, until it's fixed, you can't do anything aside from trying to not use the extension.

While GNU C has some great extensions, if you want to write portable c code, try to avoid using any GNU C extension.

Borland x86 inlined assembler; get a label's address?

Last time I tried to make some assembly code Borland-compatible I came across the limitation that you can't forward-reference labels. Not sure if that's what you're running into here.

MSVC Warning Number for -Wunused-label

-Wunused-label is C4102 in visual studio

how to set labels in inline assembly?

Use offset variableName to access variables from inline assembly. See reference here.

Example:

char format[] = "%s %s\n";
char hello[] = "Hello";
char world[] = "world";
int main( void )
{
   __asm
   {
      mov  eax, offset world
      push eax
      mov  eax, offset hello
      push eax
      mov  eax, offset format
      push eax
      call printf
      //clean up the stack so that main can exit cleanly
      //use the unused register ebx to do the cleanup
      pop  ebx
      pop  ebx
      pop  ebx
   }
}

Get linear address of FS:[0] in 32-bit protected mode / MSVC inline asm

Assuming FS points to the Windows Thread Information Block (TIB), also known as the Thread Environment Block (TEB), you get the linear address of the TIB by reading the 32-bit value at fs:[0x18]. The best way to do this in Visual C++ is to use the __readfsdword intrinsic:

TEB *teb = (TEB *) __readfsdword(0x18);

How can I find all of the labels for a particular TFS project sub-folder?

In Visual Studio, in the Source Control Explorer window, right-click the sub-folder for which you want to list the relevant labels and pick View History from the context menu. In the History window that should appear, there should be a sub-tab Labels (as highlighted below) that lists labels applied to that sub-folder (but not specific items in that sub-folder).

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