C Structure using Pointer as Array

[thepowersgang]

I'm trying to fill a structure using the {} method but the string contained in the first field does not seem to store as a pointer to the string, but actually stores the string's data IN the pointer.

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...
typedef struct {
	char	*Name;
	tClass	*Classes;
	 int	ClassCount;
} tNamespace;
...
tNamespace	gaCommonNamespaces[] = {
	{"Stdlib", gaCommonClasses_Stdlib, sizeof(gaCommonClasses_Stdlib)/sizeof(tClass)},
	{"System", gaCommonClasses_System, sizeof(gaCommonClasses_System)/sizeof(tClass)}
};
..

When I do

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printf("String Pointer address = 0x%x\n", gaCommonNamespaces[0].Name);

I get the value 0x6C647453, which seems to be the ASCII representation of the letters 'Stdl' instead of a pointer.
Does anyone know why this happens?

[CodeCat]

Not sure why it happens, but a solution could be to simply put an & before the string literal.

[Solar]

Guessing, and trial & error, are very poor guides in the realm of programming.

Without seeing the rest of your code, or knowing anything about your environment, it could be anything from a syntax error somewhere to a borked printf() implementation...

Can you give a minimal example with which the problem can be reproduced? (Usually the first step towards finding out what's going on.) With that I mean a minimal int main() that compiles on your machine, exhibits the problem, and has been copied into your webbrowser verbatim.

[CodeCat]

It doesn't have anything to do with his environment really. This is presumably behaviour that is standard to the C language itself. When you initialise a struct, you provide values for each of its members. Structs can also contain arrays, which can be initialised in the same way:

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struct A
{
char stuff[10];
};

struct A foo = {"test!"};

Afterwards, foo.stuff will be an array containing the string "test!".

However, when you provide an array to initialise a member with, the compiler has no idea whether you intended to initialise that member with the array, or with a pointer to that array. It therefore copies the array itself into the struct, rather than a pointer to it, even if the types don't match. I've no idea why the C standard allows this, but apparently it happens.

[thepowersgang]

I just found the bug, I was defining gaCommonNamespaces as a pointer instead of an array in the file that did the printf. My excuse is that I was tired when I wrote it.

[Solar]

It doesn't have anything to do with his environment really. This is presumably behaviour that is standard to the C language itself.

No.

However, when you provide an array to initialise a member with, the compiler has no idea whether you intended to initialise that member with the array, or with a pointer to that array.

In his example the member was a char *, not a char [], so initializing that member with a string literal is a well-defined operation for the compiler: Have the member pointer point to somewhere in the .rodata (or .data) section where the string literal resides.

I've no idea why the C standard allows this, but apparently it happens.

It doesn't, and it doesn't.

[iammisc]

instead of using %x, why not %p?

[DeletedAccount]

%x -> for hex values
%p -> for pointers

hint : Dependending upon scanf/printf for type conversion is a big error , and may print out garbage value at times .

Regards
Shrek