3 files changed, 22 insertions, 4 deletions
diff --git a/src/server/shared/Debugging/Errors.cpp b/src/server/shared/Debugging/Errors.cpp
index 0621cfa5b6d..8b1b9454850 100644
--- a/src/server/shared/Debugging/Errors.cpp
+++ b/src/server/shared/Debugging/Errors.cpp
@@ -21,6 +21,7 @@
 #include <cstdio>
 #include <cstdlib>
 #include <thread>
+#include <cstdarg>
 
 namespace Trinity {
 
@@ -32,6 +33,21 @@ void Assert(char const* file, int line, char const* function, char const* messag
     exit(1);
 }
 
+void Assert(char const* file, int line, char const* function, char const* message, char const* format, ...)
+{
+    va_list args;
+    va_start(args, format);
+
+    fprintf(stderr, "\n%s:%i in %s ASSERTION FAILED:\n  %s ", file, line, function, message);
+    vfprintf(stderr, format, args);
+    fprintf(stderr, "\n");
+    fflush(stderr);
+
+    va_end(args);
+    *((volatile int*)NULL) = 0;
+    exit(1);
+}
+
 void Fatal(char const* file, int line, char const* function, char const* message)
 {
     fprintf(stderr, "\n%s:%i in %s FATAL ERROR:\n  %s\n",
diff --git a/src/server/shared/Debugging/Errors.h b/src/server/shared/Debugging/Errors.h
index 218acfa453e..e6da19eb00d 100644
--- a/src/server/shared/Debugging/Errors.h
+++ b/src/server/shared/Debugging/Errors.h
@@ -23,8 +23,8 @@
 
 namespace Trinity
 {
-
     DECLSPEC_NORETURN void Assert(char const* file, int line, char const* function, char const* message) ATTR_NORETURN;
+    DECLSPEC_NORETURN void Assert(char const* file, int line, char const* function, char const* message, char const* format, ...) ATTR_NORETURN ATTR_PRINTF(5, 6);
 
     DECLSPEC_NORETURN void Fatal(char const* file, int line, char const* function, char const* message) ATTR_NORETURN;
 
@@ -42,7 +42,7 @@ namespace Trinity
 #define ASSERT_END
 #endif
 
-#define WPAssert(cond) ASSERT_BEGIN do { if (!(cond)) Trinity::Assert(__FILE__, __LINE__, __FUNCTION__, #cond); } while(0) ASSERT_END
+#define WPAssert(cond, ...) ASSERT_BEGIN do { if (!(cond)) Trinity::Assert(__FILE__, __LINE__, __FUNCTION__, #cond, ##__VA_ARGS__); } while(0) ASSERT_END
 #define WPFatal(cond, msg) ASSERT_BEGIN do { if (!(cond)) Trinity::Fatal(__FILE__, __LINE__, __FUNCTION__, (msg)); } while(0) ASSERT_END
 #define WPError(cond, msg) ASSERT_BEGIN do { if (!(cond)) Trinity::Error(__FILE__, __LINE__, __FUNCTION__, (msg)); } while(0) ASSERT_END
 #define WPWarning(cond, msg) ASSERT_BEGIN do { if (!(cond)) Trinity::Warning(__FILE__, __LINE__, __FUNCTION__, (msg)); } while(0) ASSERT_END
diff --git a/src/server/shared/Packets/ByteBuffer.h b/src/server/shared/Packets/ByteBuffer.h
index f7d27697f24..d65b6c58a51 100644
--- a/src/server/shared/Packets/ByteBuffer.h
+++ b/src/server/shared/Packets/ByteBuffer.h
@@ -118,7 +118,6 @@ class ByteBuffer
         template <typename T> void append(T value)
         {
             static_assert(std::is_fundamental<T>::value, "append(compound)");
-            FlushBits();
             EndianConvert(value);
             append((uint8 *)&value, sizeof(value));
         }
@@ -128,9 +127,10 @@ class ByteBuffer
             if (_bitpos == 8)
                 return;
 
+            _bitpos = 8;
+
             append((uint8 *)&_curbitval, sizeof(uint8));
             _curbitval = 0;
-            _bitpos = 8;
         }
 
         bool WriteBit(uint32 bit)
@@ -583,6 +583,8 @@ class ByteBuffer
 
             ASSERT(size() < 10000000);
 
+            FlushBits();
+
             if (_storage.size() < _wpos + cnt)
                 _storage.resize(_wpos + cnt);
             std::memcpy(&_storage[_wpos], src, cnt);