pragma-ep-1.c

gcc-you can use this code to learn something about gcc, and inquire further into linux,

/* { dg-do compile { target *-*-osf5* } } */
/* { dg-final { scan-assembler "xyzzy_one" } } */
/* { dg-final { scan-assembler "xyzzy_two" } } */
/* { dg-final { scan-assembler "xyzzz_three" } } */
/* { dg-final { scan-assembler "four" } } */
/* { dg-final { scan-assembler-not "_four" } } */

#ifndef __PRAGMA_EXTERN_PREFIX
#error
#endif

#pragma extern_prefix "xyzzy_"

extern "C" int one(void);
extern "C" int two(void);

#pragma extern_prefix "xyzzz_"

extern "C" int three(void);

#pragma extern_prefix ""

extern "C" int four(void);

void *p[] = {
  (void *) one, (void *) two, (void *) three, (void *) four
};