Rename the pointer argument of crc64_invert for clarity

include/CRC64.h

@@ -84,7 +84,7 @@ uint64_t crc64_omp(const void *input, size_t nbytes);
  * Calculate the 'check bytes' for the provided CRC64. If these bytes are
  * appended to the original buffer, then the new total CRC64 should be -1.
  */
-void crc64_invert(uint64_t cs, void *buffer);
+void crc64_invert(uint64_t cs, void *check_bytes);
 
 /*
  * Given the CRC64 of the first part of a buffer, and the CRC64 and length of

src/CRC64.c

@@ -1319,8 +1319,8 @@ uint64_t crc64(const void *input, size_t nbytes) {
 
 // Calculate the 'check bytes' for the provided checksum. If these bytes are
 // appended to the original buffer, then the new total checksum should be -1.
-void crc64_invert(uint64_t cs, void *buffer) {
-  unsigned char *bytes = (unsigned char *) buffer;
+void crc64_invert(uint64_t cs, void *check_bytes) {
+  unsigned char *bytes = (unsigned char *) check_bytes;
   cs ^= UINT64_C(0xffffffffffffffff);
 
   // The CRC is self-inverting (in big-endian, so the bit-reversed CRC is