X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Falloca.c;h=c7e91ab9336cf44d589d13a077d120518c9ce6e2;hb=a76da24458afd3758386c60ab5c0bed4e100509e;hp=2f5e27ec69595ad95886271b219047b2070a4114;hpb=6f5772995bee8b337fdd2fea5aea6f3fcb59fa36;p=gnulib.git diff --git a/lib/alloca.c b/lib/alloca.c index 2f5e27ec6..c7e91ab93 100644 --- a/lib/alloca.c +++ b/lib/alloca.c @@ -93,25 +93,15 @@ 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 */ @@ -154,10 +144,7 @@ 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