hash: Add explicit typecasts to fix C++ compilation issues

C++ does not allow implicit conversion from void pointer to a specific
pointer type. This change removes the cast from uint32_t* to void* in
`hash_words_32aligned` and adds an explicit typecast from uint32_t* to
uint64_t* in `hash_words_inline`.

This issue was initially discovered on G++ v9.2.0 when a downstream C++
application included the hash.h header file and was compiled on an AMD
Ryzen Zen 2 CPU (__SSE4_2__ && __x86_64__). On the latest G++ version,
it would throw an error. On the latest GCC version with `-Wc++-compat`,
it would throw a warning.

Acked-by: Mike Pattrick <[email protected]>
Signed-off-by: James Raphael Tiovalen <[email protected]>
Signed-off-by: 0-day Robot <[email protected]>

lib/hash.h

@@ -198,9 +198,8 @@ hash_finish32(uint64_t hash, uint32_t final, uint32_t semifinal)
 }
 
 static inline uint32_t
-hash_words_32aligned(const uint32_t *p_, size_t n_words, uint32_t basis)
+hash_words_32aligned(const uint32_t *p, size_t n_words, uint32_t basis)
 {
-    const uint32_t *p = (const void *) p_;
     uint32_t hash1 = basis;
     uint32_t hash2 = 0;
     uint32_t hash3 = n_words;
@@ -254,7 +253,7 @@ hash_words_32aligned(const uint32_t *p_, size_t n_words, uint32_t basis)
 static inline uint32_t
 hash_words_inline(const uint32_t *p_, size_t n_words, uint32_t basis)
 {
-    const uint64_t *p = (const void *)p_;
+    const uint64_t *p = ALIGNED_CAST(const uint64_t *, p_);
     uint64_t hash1 = basis;
     uint64_t hash2 = 0;
     uint64_t hash3 = n_words;