X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=gnu%2Falloca.c;h=b14bba75a7e70e6ea8eab36be84dd3dabe4fd291;hb=daa269958ad8d50ef8154ccb65e58acaf7a6dd99;hp=a16fa392568417d5ffbce230f971ec7f760bd051;hpb=1a44d77d50f4fb37c0410eed04b82303624ea2ec;p=debian%2Ftar diff --git a/gnu/alloca.c b/gnu/alloca.c index a16fa392..b14bba75 100644 --- a/gnu/alloca.c +++ b/gnu/alloca.c @@ -95,25 +95,15 @@ long i00afunc (); static int stack_dir; /* 1 or -1 once known. */ # define STACK_DIR stack_dir -static void -find_stack_direction (char **ptr) +static int +find_stack_direction (int *addr, int depth) { - auto char dummy; /* To get stack address. */ - - if (*ptr == NULL) - { /* Initial entry. */ - *ptr = ADDRESS_FUNCTION (dummy); - - find_stack_direction (ptr); /* Recurse once. */ - } - else - { - /* Second entry. */ - if (ADDRESS_FUNCTION (dummy) > *ptr) - stack_dir = 1; /* Stack grew upward. */ - else - stack_dir = -1; /* Stack grew downward. */ - } + int dir, dummy = 0; + if (! addr) + addr = &dummy; + *addr = addr < &dummy ? 1 : addr == &dummy ? 0 : -1; + dir = depth ? find_stack_direction (addr, depth - 1) : 0; + return dir + dummy; } # endif /* STACK_DIRECTION == 0 */ @@ -156,10 +146,7 @@ alloca (size_t size) # if STACK_DIRECTION == 0 if (STACK_DIR == 0) /* Unknown growth direction. */ - { - char *addr = NULL; /* Address of first `dummy', once known. */ - find_stack_direction (&addr); - } + STACK_DIR = find_stack_direction (NULL, (size & 1) + 20); # endif /* Reclaim garbage, defined as all alloca'd storage that @@ -490,4 +477,4 @@ i00afunc (long address) # endif /* CRAY */ # endif /* no alloca */ -#endif /* not GCC version 3 */ +#endif /* not GCC 2 */