diff --git a/src/include/blobhash.h b/src/include/blobhash.h
index 597884e4c9..97f2065ce3 100644
--- a/src/include/blobhash.h
+++ b/src/include/blobhash.h
@@ -14,33 +14,40 @@
 #ifndef CEPH_BLOBHASH_H
 #define CEPH_BLOBHASH_H
 
+#include <cstdint>
 #include "hash.h"
 
-/*
-- this is to make some of the STL types work with 64 bit values, string hash keys, etc.
-- added when i was using an old STL.. maybe try taking these out and see if things 
-  compile now?
-*/
-
 class blobhash {
 public:
-  uint32_t operator()(const char *p, unsigned len) {
-    static rjhash<uint32_t> H;
-    uint32_t acc = 0;
+  uint32_t operator()(const void* p, size_t len) {
+    static rjhash<std::uint32_t> H;
+    std::uint32_t acc = 0;
+    auto buf = static_cast<const unsigned char*>(p);
     while (len >= sizeof(acc)) {
-      acc ^= *(uint32_t*)p;
-      p += sizeof(uint32_t);
-      len -= sizeof(uint32_t);
+      acc ^= unaligned_load(buf);
+      buf += sizeof(std::uint32_t);
+      len -= sizeof(std::uint32_t);
     }
-    int sh = 0;
-    while (len) {
-      acc ^= (uint32_t)*p << sh;
-      sh += 8;
-      len--;
-      p++;
+    // handle the last few bytes of p[-(len % 4):]
+    switch (len) {
+    case 3:
+      acc ^= buf[2] << 16;
+      [[fallthrough]];
+    case 2:
+      acc ^= buf[1] << 8;
+      [[fallthrough]];
+    case 1:
+      acc ^= buf[0];
+      [[fallthrough]];
     }
     return H(acc);
   }
+private:
+  static inline std::uint32_t unaligned_load(const unsigned char* p) {
+    std::uint32_t result;
+    __builtin_memcpy(&result, p, sizeof(result));
+    return result;
+  }
 };
 
 
diff --git a/src/msg/msg_types.h b/src/msg/msg_types.h
index b6952ca498..576b7d6b8a 100644
--- a/src/msg/msg_types.h
+++ b/src/msg/msg_types.h
@@ -566,7 +566,7 @@ namespace std {
     size_t operator()( const entity_addr_t& x ) const
     {
       static blobhash H;
-      return H((const char*)&x, sizeof(x));
+      return H(&x, sizeof(x));
     }
   };
 } // namespace std