preprocessor directive #if

[mahaju]

I saw

Code: Select all

#elif defined(TFM_X86_64)

in a very long sample code

is it same as

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#elif defined TFM_X86_64

??
Just checking

Thanks

[technosaurus]

I am away right now, Try:

#define TFM
#define _X86_64

#ifdef TFM_X86_64
printf("merged defs?");
#endif

[mahaju]

Code: Select all

#include<stdio.h>
#define TFM
#define _X86_64

#ifdef TFM_X86_64
printf("merged defs?");
#endif

it says

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C:/Program Files/CodeBlocks/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../libmingw
32.a(main.o):main.c:(.text+0x104): undefined reference to `_WinMain@16'
collect2: ld returned 1 exit status

This is in gcc in Windows 7
Why isn't it compiling? The code looks simple enough

[technosaurus]

Code: Select all

#include<stdio.h>
#define TFM
#define _X86_64

#ifdef TFM_X86_64
printf("merged defs?");
#endif

it says

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C:/Program Files/CodeBlocks/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../libmingw
32.a(main.o):main.c:(.text+0x104): undefined reference to `_WinMain@16'
collect2: ld returned 1 exit status

This is in gcc in Windows 7
Why isn't it compiling? The code looks simple enough

The ifdefs code needs to be in a main function ... I.figured if you were asking about ifdefs you would know that. Sorry, don't know the windows main functions.

[mahaju]

Oh Yeah
The main function
I knew I forgot something in this code

[mahaju]

Code: Select all

#include<stdio.h>
#define TFM
#define _X86_64

#ifdef TFM_X86_64
printf("merged defs?");
#endif

int main(){return 0;}

Compiles fine
When I run it my AVG 2011 Free Edition antivirus says it's potential threat

What happened here??

And then same for

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#include<stdio.h>
int main(){
	#define TFM
	#define _X86_64

	#ifdef TFM_X86_64
	printf("merged defs?");
	#endif
	return 0;
}

Why is that?

[technosaurus]

Did it print "merged defs" on the command line?

[mahaju]

No
The antivirus is blocking it (1st code)
and the second one says "Access Denied" when it is run, then it's blocked by the antivirus
and it's not because my computer's infected either, I can compile all other code using gcc and none of them show up as Potential threats in the antivirus
I think it's got something to do with those predefined macro names

OK I changed the macro names into some random texts and it's still showing the same problems why is that?

[mahaju]

Ok

I tried both the codes given above in Windows XP as well as puppy Linux 5.2.8 in VMWare player. They don't have antivirus installed so compiled executable is not blocked, however, it doesn't apparently do anything

Why is it like this?