sizeof in preprocessor

How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
..............
#endif

I want compile different pieces of code for different platforms

[Nick Hounsome]

"<- Chameleon ->" <ch******@hotmail.NOSPAM.com> wrote in message
news:c4**********@nic.grnet.gr...

How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
.............
#endif

I want compile different pieces of code for different platforms

You can't in the preprocessor but you could use
specialization of templates based on sizeof

[Rolf Magnus]

- Chameleon - wrote:

How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
.............
#endif

You can't. the value of sizeof() is not evaluated by the preprocessor.
Therefore, you can't use it in preprocessor conditionals. You could do:

#include <climits>
#define MY_INT_MAX some_value
#if INT_MAX < MY_INT_MAX
//something
#else
//something else
#endif

or you use templates: (untested)

template <bool b>
void my_function_internal()
{
//something
}

template <>
void my_function_internal<false>()
{
//something else
}

void my_function()
{
my_function_internal<(sizeof(int) < sizeof(my_int))>();
}

[Nick Hounsome]

"<- Chameleon ->" <ch******@hotmail.NOSPAM.com> wrote in message
news:c4**********@nic.grnet.gr...

How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
.............
#endif

I want compile different pieces of code for different platforms

You can't in the preprocessor but you could use
specialization of templates based on sizeof

[Rolf Magnus]

- Chameleon - wrote:

How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
.............
#endif

You can't. the value of sizeof() is not evaluated by the preprocessor.
Therefore, you can't use it in preprocessor conditionals. You could do:

#include <climits>
#define MY_INT_MAX some_value
#if INT_MAX < MY_INT_MAX
//something
#else
//something else
#endif

or you use templates: (untested)

template <bool b>
void my_function_internal()
{
//something
}

template <>
void my_function_internal<false>()
{
//something else
}

void my_function()
{
my_function_internal<(sizeof(int) < sizeof(my_int))>();
}

[Jeff Schwab]

<- Chameleon -> wrote:

How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
.............
#endif

I want compile different pieces of code for different platforms

I'd love to answer this for you, but since I'm Jewish, I assume you
don't want my help.

http://groups.google.com/groups?q=ch...rnet.gr&rnum=1

[Jeff Schwab]

<- Chameleon -> wrote:

How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
.............
#endif

I want compile different pieces of code for different platforms

I'd love to answer this for you, but since I'm Jewish, I assume you
don't want my help.

http://groups.google.com/groups?q=ch...rnet.gr&rnum=1

> > How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
.............
#endif

I want compile different pieces of code for different platforms

I'd love to answer this for you, but since I'm Jewish, I assume you
don't want my help.

your answer is off-topic

> > How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
.............
#endif

I want compile different pieces of code for different platforms

I'd love to answer this for you, but since I'm Jewish, I assume you
don't want my help.

your answer is off-topic

[Jeff Schwab]

<- Chameleon -> wrote:

How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
.............
#endif

I want compile different pieces of code for different platforms

I'd love to answer this for you, but since I'm Jewish, I assume you
don't want my help.

your answer is off-topic

Yes, that's what [OT] in the subject line means.

[Jeff Schwab]

<- Chameleon -> wrote:

How can I write this correctly?

#if sizeof(int) < sizeof(my_int)
.............
#endif

I want compile different pieces of code for different platforms

I'd love to answer this for you, but since I'm Jewish, I assume you
don't want my help.

your answer is off-topic

Yes, that's what [OT] in the subject line means.