/* This file is only used if enabled in the build system, in which case it is * included automatically via command line options. It is not included * explicitly by any source files or other headers. Its purpose is to * override default visibilities to reduce the size and performance costs * of position-independent code. */ #ifndef CRT #ifdef SHARED /* For shared libc.so, all symbols should be protected, but some toolchains * fail to support copy relocations for protected data, so exclude all * exported data symbols. */ __attribute__((__visibility__("default"))) extern struct _IO_FILE *const stdin, *const stdout, *const stderr; __attribute__((__visibility__("default"))) extern int optind, opterr, optopt, optreset, __optreset, getdate_err, h_errno, daylight, __daylight, signgam, __signgam; __attribute__((__visibility__("default"))) extern long timezone, __timezone; __attribute__((__visibility__("default"))) extern char *optarg, **environ, **__environ, *tzname[2], *__tzname[2], *__progname, *__progname_full; #pragma GCC visibility push(protected) #elif defined(__PIC__) /* If building static libc.a as position-independent code, try to make * everything hidden except possibly-undefined weak references. */ __attribute__((__visibility__("default"))) extern void (*const __init_array_start)(), (*const __init_array_end)(), (*const __fini_array_start)(), (*const __fini_array_end)(); #pragma GCC visibility push(hidden) #endif #endif