fix xgboost build failure introduced by allgather interface (#129)

* fix missing allgether rabit declaration

* fix allgather signature mismatch

* fix type conversion

* fix GetRingPrevRank

src/allreduce_mock.h

@@ -71,7 +71,8 @@ class AllreduceMock : public AllreduceRobust {
     this->Verify(MockKey(rank, version_number, seq_counter, num_trial), "Allgather");
     double tstart = utils::GetTime();
     AllreduceRobust::Allgather(sendrecvbuf, total_size,
-                                   slice_begin, slice_end, size_prev_slice);
+                                   slice_begin, slice_end,
+                                   size_prev_slice, _file, _line, _caller);
     tsum_allgather += utils::GetTime() - tstart;
   }
   virtual void Broadcast(void *sendrecvbuf_, size_t total_size, int root,

src/c_api.cc

@@ -131,33 +131,54 @@ void Allgather(void *sendrecvbuf_,
   switch (enum_dtype) {
   case kChar:
     type_size = sizeof(char);
+    rabit::Allgather(static_cast<char*>(sendrecvbuf_), total_size * type_size,
+      beginIndex * type_size, (beginIndex + size_node_slice) * type_size,
+      size_prev_slice * type_size);
     break;
   case kUChar:
     type_size = sizeof(unsigned char);
+    rabit::Allgather(static_cast<unsigned char*>(sendrecvbuf_), total_size * type_size,
+      beginIndex * type_size, (beginIndex + size_node_slice) * type_size,
+      size_prev_slice * type_size);
     break;
   case kInt:
     type_size = sizeof(int);
+    rabit::Allgather(static_cast<int*>(sendrecvbuf_), total_size * type_size,
+      beginIndex * type_size, (beginIndex + size_node_slice) * type_size,
+      size_prev_slice * type_size);
     break;
   case kUInt:
     type_size = sizeof(unsigned);
+    rabit::Allgather(static_cast<unsigned*>(sendrecvbuf_), total_size * type_size,
+      beginIndex * type_size, (beginIndex + size_node_slice) * type_size,
+      size_prev_slice * type_size);
     break;
   case kLong:
     type_size = sizeof(int64_t);
+    rabit::Allgather(static_cast<int64_t*>(sendrecvbuf_), total_size * type_size,
+      beginIndex * type_size, (beginIndex + size_node_slice) * type_size,
+      size_prev_slice * type_size);
     break;
   case kULong:
     type_size = sizeof(uint64_t);
+    rabit::Allgather(static_cast<uint64_t*>(sendrecvbuf_), total_size * type_size,
+      beginIndex * type_size, (beginIndex + size_node_slice) * type_size,
+      size_prev_slice * type_size);
     break;
   case kFloat:
     type_size = sizeof(float);
+    rabit::Allgather(static_cast<float*>(sendrecvbuf_), total_size * type_size,
+      beginIndex * type_size, (beginIndex + size_node_slice) * type_size,
+      size_prev_slice * type_size);
     break;
   case kDouble:
     type_size = sizeof(double);
+    rabit::Allgather(static_cast<double*>(sendrecvbuf_), total_size * type_size,
+      beginIndex * type_size, (beginIndex + size_node_slice) * type_size,
+      size_prev_slice * type_size);
     break;
   default: utils::Error("unknown data_type");
   }
-  engine::Allgather
-    (sendrecvbuf_, total_size * type_size, beginIndex * type_size,
-    (beginIndex + size_node_slice) * type_size, size_prev_slice * type_size);
 }
 
 // wrapper for serialization
@@ -251,11 +272,11 @@ void RabitAllgather(void *sendrecvbuf_,
                         size_t size_prev_slice,
                         int enum_dtype) {
   rabit::c_api::Allgather(sendrecvbuf_,
-                              total_size,
-                              beginIndex,
-                              size_node_slice,
-                              size_prev_slice,
-                              enum_dtype);
+                          total_size,
+                          beginIndex,
+                          size_node_slice,
+                          size_prev_slice,
+                          static_cast<rabit::engine::mpi::DataType>(enum_dtype));
 }
 
 

src/engine.cc

@@ -88,8 +88,12 @@ IEngine *GetEngine() {
 void Allgather(void *sendrecvbuf_, size_t total_size,
                    size_t slice_begin,
                    size_t slice_end,
-                   size_t size_prev_slice) {
-  GetEngine()->Allgather(sendrecvbuf_, total_size, slice_begin, slice_end, size_prev_slice);
+                   size_t size_prev_slice,
+                   const char* _file,
+                   const int _line,
+                   const char* _caller) {
+  GetEngine()->Allgather(sendrecvbuf_, total_size, slice_begin,
+    slice_end, size_prev_slice, _file, _line, _caller);
 }
 
 

src/engine_empty.cc

@@ -26,17 +26,18 @@ class EmptyEngine : public IEngine {
     version_number = 0;
   }
   virtual void Allgather(void *sendrecvbuf_,
-                             size_t total_size,
-                             size_t slice_begin,
-                             size_t slice_end,
-                             size_t size_prev_slice,
-                             const char* _file,
-                             const int _line,
-                             const char* _caller) {
+                         size_t total_size,
+                         size_t slice_begin,
+                         size_t slice_end,
+                         size_t size_prev_slice,
+                         const char* _file,
+                         const int _line,
+                         const char* _caller) {
     utils::Error("EmptyEngine:: Allgather is not supported");
   }
   virtual int GetRingPrevRank(void) const {
     utils::Error("EmptyEngine:: GetRingPrevRank is not supported");
+    return -1;
   }
   virtual void Allreduce(void *sendrecvbuf_,
                          size_t type_nbytes,