Re: [Crash-utility] target compilation?
Jun Koi wrote:
Hi,
I looked at configure.c, and find some code like this:
void
get_current_configuration(void)
{
FILE *fp;
static char buf[512];
char *p;
#ifdef __alpha__
target_data.target = ALPHA;
#endif
#ifdef __i386__
target_data.target = X86;
#endif
#ifdef __powerpc__
target_data.target = PPC;
#endif
#ifdef __ia64__
target_data.target = IA64;
#endif
...
}
I have few questions:
- Is it correct that the above code want to find out the architecture
(means target here) we are compiling our code on?
Exactly.
- Who defined those architectures in the above code, like "__i386__"
(in the check "#ifdef __i386__")? I guessed that the architecture is
defined in a particular prototype file in /usr/include, but cannot
find anything there. So I think that those macros are defined by
compilation process of crash, but again I dont see anywhere in the
source doing that.
I forget where they are defined, but they're available to any compiled
object without any explicit #include's, like this example on my x86_64
machine:
# cat tmp.c
main()
{
#ifdef __x86_64__
printf("hello world\n");
#endif
}
# make tmp
cc tmp.c -o tmp
# ./tmp
hello world
#
Dave