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Remove type punning from hash function.

	It was always a little ugly, and it seems to have caused
	an issue with -O3 builds on OpenBSD.

--- a/util/htab.c

+++ b/util/htab.c

@@ -254,7 +254,10 @@

 	return !memcmp(a->buf, b->buf, a->len);

 }

-ulong ptrhash(void *key) { return inthash((uintptr_t)key); }

+ulong ptrhash(void *key)

+{ 

+	return inthash((uintptr_t)key);

+}

 ulong inthash(uint64_t key)

 {

@@ -275,15 +278,16 @@

 {

 	uint32_t m = 0x5bd1e995;

 	uint32_t r = 24;

-	uint32_t h, k;

-	uint32_t *data;

-	uint8_t *buf;

+	uint32_t h, k, n;

+	uint8_t *p;

-	buf = ptr;

-	data = (uint32_t*)buf;

 	h = Seed ^ len;

-	while (len >= 4) {

-		k = *data;

+	n = len & ~0x3ull;

+	for (p = ptr; p != ptr + n; p += 4) {

+		k = (p[0] <<  0) |

+			(p[1] <<  8) |

+			(p[2] << 16) |

+			(p[3] << 24);

 		k *= m;

 		k ^= k >> r;

@@ -291,17 +295,15 @@

 		h *= m;

 		h ^= k;

-		data++;

-		len -= sizeof(*data);

 	}

-	switch (len) {

+	switch (len & 0x3) {

 	case 3:

-		h ^= buf[2] << 16;

+		h ^= p[2] << 16;

 	case 2:

-		h ^= buf[1] << 8;

+		h ^= p[1] << 8;

 	case 1:

-		h ^= buf[0] << 0;

+		h ^= p[0] << 0;

 	default:

 		break;

 	};