ccan: update to faster and correct crc32c implementation.

I decided to try a faster implementation, only to find our crc32c was
not correct!  Ouch.

I removed the crc32c functions from ccan/crc, and added a new crc32c
module which has the Mark Adler x86-64-optimized variants.

We bump gossip_store version again, since csums have changed.

Signed-off-by: Rusty Russell <[email protected]>

Makefile

@@ -63,7 +63,7 @@ CCAN_OBJS :=					\
 	ccan-bitmap.o				\
 	ccan-bitops.o				\
 	ccan-breakpoint.o			\
-	ccan-crc.o				\
+	ccan-crc32c.o				\
 	ccan-crypto-hmac.o			\
 	ccan-crypto-hkdf.o			\
 	ccan-crypto-ripemd160.o			\
@@ -123,7 +123,7 @@ CCAN_HEADERS :=						\
 	$(CCANDIR)/ccan/compiler/compiler.h		\
 	$(CCANDIR)/ccan/container_of/container_of.h	\
 	$(CCANDIR)/ccan/cppmagic/cppmagic.h		\
-	$(CCANDIR)/ccan/crc/crc.h			\
+	$(CCANDIR)/ccan/crc32c/crc32c.h			\
 	$(CCANDIR)/ccan/crypto/hkdf_sha256/hkdf_sha256.h \
 	$(CCANDIR)/ccan/crypto/hmac_sha256/hmac_sha256.h \
 	$(CCANDIR)/ccan/crypto/ripemd160/ripemd160.h	\
@@ -601,7 +601,7 @@ ccan-noerr.o: $(CCANDIR)/ccan/noerr/noerr.c
 	$(CC) $(CFLAGS) -c -o $@ $<
 ccan-str-hex.o: $(CCANDIR)/ccan/str/hex/hex.c
 	$(CC) $(CFLAGS) -c -o $@ $<
-ccan-crc.o: $(CCANDIR)/ccan/crc/crc.c
+ccan-crc32c.o: $(CCANDIR)/ccan/crc32c/crc32c.c
 	$(CC) $(CFLAGS) -c -o $@ $<
 ccan-crypto-hmac.o: $(CCANDIR)/ccan/crypto/hmac_sha256/hmac_sha256.c
 	$(CC) $(CFLAGS) -c -o $@ $<

ccan/README

@@ -1,3 +1,3 @@
 CCAN imported from http://ccodearchive.net.
 
-CCAN version: init-2473-g7623d082
+CCAN version: init-2481-gce4660aa

ccan/ccan/compiler/compiler.h

@@ -286,4 +286,19 @@
 #define LAST_ARG_NULL
 #endif
 
+#if HAVE_BUILTIN_CPU_SUPPORTS
+/**
+ * cpu_supports - test if current CPU supports the named feature.
+ *
+ * This takes a literal string, and currently only works on glibc platforms.
+ *
+ * Example:
+ * if (cpu_supports("mmx"))
+ *	printf("MMX support engaged!\n");
+ */
+#define cpu_supports(x) __builtin_cpu_supports(x)
+#else
+#define cpu_supports(x) 0
+#endif /* HAVE_BUILTIN_CPU_SUPPORTS */
+
 #endif /* CCAN_COMPILER_H */