Fix for https://github.com/lemire/simdjson/issues/58 (#168)

src/parsedjson.cpp

@@ -74,7 +74,13 @@ bool ParsedJson::allocateCapacity(size_t len, size_t maxdepth) {
 
       return false;
     }
-
+    /*
+    // We do not need to initialize this content for parsing, though we could
+    // need to initialize it for safety.
+    memset(string_buf, 0 , localstringcapacity); 
+    memset(structural_indexes, 0, max_structures * sizeof(uint32_t)); 
+    memset(tape, 0, localtapecapacity * sizeof(uint64_t)); 
+    */
     bytecapacity = len;
     depthcapacity = maxdepth;
     tapecapacity = localtapecapacity;

src/stage2_build_tape.cpp

@@ -72,6 +72,9 @@ really_inline bool is_valid_null_atom(const uint8_t *loc) {
  ***********/
 WARN_UNUSED  ALLOW_SAME_PAGE_BUFFER_OVERRUN_QUALIFIER LENIENT_MEM_SANITIZER
 int unified_machine(const uint8_t *buf, size_t len, ParsedJson &pj) {
+#ifndef ALLOW_SAME_PAGE_BUFFER_OVERRUN
+  memset((uint8_t*)buf + len, 0, SIMDJSON_PADDING); // to please valgrind
+#endif
   uint32_t i = 0; // index of the structural character (0,1,2,3...)
   uint32_t idx;   // location of the structural character in the input (buf)
   uint8_t c; // used to track the (structural) character we are looking at, updated