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A dllimport variable is accessed indirectly through a variable

Consider the below code:

extern __declspec(dlli mport) int myvariable;
template<const int *p>
class MyClass{
public:
static void myfunction(){
} };

int main(void){
MyClass<&myvari able>::myfuncti on();
return 0; }
"A dllimport variable is accessed indirectly through a variable and
therefore does not have a constant address". Is this statement valid /
correct ???

Feb 11 '06 #1
2 1957
On 10 Feb 2006 19:32:06 -0800, hs******@gmail. com wrote in
comp.lang.c++:
Consider the below code:

extern __declspec(dlli mport) int myvariable;
template<const int *p>
class MyClass{
public:
static void myfunction(){
} };

int main(void){
MyClass<&myvari able>::myfuncti on();
return 0; }
"A dllimport variable is accessed indirectly through a variable and
therefore does not have a constant address". Is this statement valid /
correct ???


C++ does not have "dllimport" variables, making your question
off-topic here. DLLs are a mechanism of your operating, supported by
non-standard extensions of your compiler.

You need to ask this in a group like
news:comp.os.ms-windows.program mer.win32 or one of Microsoft's support
groups in the news:microsoft. public.* family.

--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
comp.lang.c http://c-faq.com/
comp.lang.c++ http://www.parashift.com/c++-faq-lite/
alt.comp.lang.l earn.c-c++
http://www.contrib.andrew.cmu.edu/~a...FAQ-acllc.html
Feb 11 '06 #2
> "A dllimport variable is accessed indirectly through a variable and
therefore does not have a constant address". Is this statement valid /
correct ???


Partially. Access to an imported variable is implemented through an
indirection via the import address table (IAT), so the following code...

__declspec(dlli mport) int myvariable;
int void f() { return myvariable; }
int * void g() { return &myvariable; }

....gets effectively translated into this:

int * const myvariable_ptr;
int void f() { return *myvariable_ptr ; }
int * void g() { return myvariable_ptr; }

where the content of myvariable_ptr is filled by the image loader
(&myvariable_pt r is the address of the myvariable import entry in the IAT
table).

-- Marek

Feb 11 '06 #3

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