C++ Pointer to unordered_map entry changes, but entry not -

i'm trying set variable of unordered_map entry "chunk" calling function using pointer entry. pointer changes value "chunkindex", map entry not

glm::ivec3 chunkindex(1, 1, 1); chunks.insert(make_pair(chunkindex, chunk())); chunk = &chunks[chunkindex]; chunk->setchunkindex(chunkindex);  logvector(chunk->chunkindex);                      // output: 1, 1, 1 logvector(chunks[chunk->chunkindex].chunkindex);   // output: 0, 0, 0 

"chunks" unordered_map of type:

typedef unordered_map<glm::ivec3, chunk, keyhash, keyequal> chunkmap; 

do know why pointer changes value, , not referenced object?

thanks in advance!

update:

chunks.insert(make_pair(chunkindex, chunk())); log((chunks.find(chunkindex) == chunks.end()) ? "true" : "false"); 

this code outputs true, inserted entry doesn't exist!

this might useful too:

struct keyhash {     size_t operator()(const glm::ivec3& k)const     {         return std::hash<int>()(k.x) ^ std::hash<int>()(k.y) ^ std::hash<int>()(k.z);     } }; struct keyequal {     bool operator()(const glm::ivec3& a, const glm::ivec3& b)const     {         return a.x < b.x || (a.x == b.x && a.y < b.y) || (a.x == b.x && a.y == b.y && a.z < b.z);     } };  typedef unordered_map<glm::ivec3, chunk, keyhash, keyequal> chunkmap; 

iterating through keys outputs 1, 1, 1

for (auto : chunks) {     logvector(it.first); } 

your keyequal doesn't implement equality. replace with:

return a.x == b.x && a.y == b.y && a.z == b.z;