diff --git a/src/Anon.cc b/src/Anon.cc
index e6b0ee3b80..ee1d296732 100644
--- a/src/Anon.cc
+++ b/src/Anon.cc
@@ -12,7 +12,7 @@
 #include "Reporter.h"
 #include "Scope.h"
 #include "ID.h"
-
+#include "IPAddr.h"
 
 AnonymizeIPAddr* ip_anonymizer[NUM_ADDR_ANONYMIZATION_METHODS] = {nullptr};
 
diff --git a/src/CompHash.cc b/src/CompHash.cc
index 7bdc3eba6a..34acd57cba 100644
--- a/src/CompHash.cc
+++ b/src/CompHash.cc
@@ -2,6 +2,9 @@
 
 #include "zeek-config.h"
 
+#include <vector>
+#include <map>
+
 #include "CompHash.h"
 #include "BroString.h"
 #include "Dict.h"
@@ -9,9 +12,7 @@
 #include "RE.h"
 #include "Reporter.h"
 #include "Func.h"
-
-#include <vector>
-#include <map>
+#include "IPAddr.h"
 
 CompositeHash::CompositeHash(IntrusivePtr<TypeList> composite_type)
 	: type(std::move(composite_type))
diff --git a/src/Desc.cc b/src/Desc.cc
index 57edf40d39..978ddff24c 100644
--- a/src/Desc.cc
+++ b/src/Desc.cc
@@ -11,6 +11,7 @@
 #include "File.h"
 #include "Reporter.h"
 #include "ConvertUTF.h"
+#include "IPAddr.h"
 
 #define DEFAULT_SIZE 128
 #define SLOP 10
diff --git a/src/IPAddr.h b/src/IPAddr.h
index a945c8b53f..ff2a188409 100644
--- a/src/IPAddr.h
+++ b/src/IPAddr.h
@@ -9,6 +9,7 @@
 #include <memory>
 
 #include "threading/SerialTypes.h"
+#include "IPAddr.h"
 
 struct ConnID;
 class BroString;
diff --git a/src/Reporter.h b/src/Reporter.h
index 9224b3e8b6..337b3664ea 100644
--- a/src/Reporter.h
+++ b/src/Reporter.h
@@ -11,7 +11,7 @@
 #include <unordered_set>
 #include <unordered_map>
 
-#include "IPAddr.h"
+#include "BroList.h"
 
 namespace analyzer { class Analyzer; }
 namespace file_analysis { class File; }
@@ -35,6 +35,9 @@ protected:
 	InterpreterException()	{}
 };
 
+class IPAddr;
+class Expr;
+
 #define FMT_ATTR __attribute__((format(printf, 2, 3))) // sic! 1st is "this" I guess.
 
 class Reporter {
diff --git a/src/RuleMatcher.cc b/src/RuleMatcher.cc
index 2e79ed185f..8b0b279e95 100644
--- a/src/RuleMatcher.cc
+++ b/src/RuleMatcher.cc
@@ -21,6 +21,7 @@
 #include "Reporter.h"
 #include "module_util.h"
 #include "Var.h"
+#include "IPAddr.h"
 
 using namespace std;
 
diff --git a/src/SerializationFormat.cc b/src/SerializationFormat.cc
index 2074cd4756..ff0ff36155 100644
--- a/src/SerializationFormat.cc
+++ b/src/SerializationFormat.cc
@@ -5,6 +5,7 @@
 #include "DebugLogger.h"
 #include "Reporter.h"
 #include "net_util.h"
+#include "IPAddr.h"
 
 const float SerializationFormat::GROWTH_FACTOR = 2.5;
 
@@ -435,4 +436,3 @@ bool BinarySerializationFormat::Write(const char* buf, int len, const char* tag)
 	uint32_t l = htonl(len);
 	return WriteData(&l, sizeof(l)) && WriteData(buf, len);
 	}
-
diff --git a/src/analyzer/protocol/mime/MIME.h b/src/analyzer/protocol/mime/MIME.h
index 50fdb8366b..bfea4ef6a2 100644
--- a/src/analyzer/protocol/mime/MIME.h
+++ b/src/analyzer/protocol/mime/MIME.h
@@ -10,6 +10,7 @@
 #include "Reporter.h"
 #include "analyzer/Analyzer.h"
 
+class TableVal;
 class StringVal;
 class Base64Converter;
 
diff --git a/src/broker/Data.h b/src/broker/Data.h
index d6578ceb99..906e5376ed 100644
--- a/src/broker/Data.h
+++ b/src/broker/Data.h
@@ -10,6 +10,11 @@ class IntrusivePtr;
 
 class ODesc;
 
+namespace threading {
+struct Value;
+struct Field;
+}
+
 namespace bro_broker {
 
 extern IntrusivePtr<OpaqueType> opaque_of_data_type;
diff --git a/src/broker/Manager.h b/src/broker/Manager.h
index a57b86057c..255b62bfa7 100644
--- a/src/broker/Manager.h
+++ b/src/broker/Manager.h
@@ -23,6 +23,7 @@
 
 class Frame;
 class Func;
+class VectorType;
 
 namespace bro_broker {
 
diff --git a/src/threading/Manager.cc b/src/threading/Manager.cc
index b4025bc68d..58d6c30dea 100644
--- a/src/threading/Manager.cc
+++ b/src/threading/Manager.cc
@@ -6,6 +6,7 @@
 #include "NetVar.h"
 #include "iosource/Manager.h"
 #include "Event.h"
+#include "IPAddr.h"
 
 using namespace threading;
 
diff --git a/src/threading/MsgThread.h b/src/threading/MsgThread.h
index 8bda2d40b8..42ce20984f 100644
--- a/src/threading/MsgThread.h
+++ b/src/threading/MsgThread.h
@@ -8,11 +8,15 @@
 #include "iosource/IOSource.h"
 #include "Flare.h"
 
+class BroObj;
+
 namespace threading {
 
 class BasicInputMessage;
 class BasicOutputMessage;
 class HeartbeatMessage;
+struct Value;
+struct Field;
 
 /**
  * A specialized thread that provides bi-directional message passing between
diff --git a/src/threading/SerialTypes.cc b/src/threading/SerialTypes.cc
index dbea04ef3a..6f3825ae2a 100644
--- a/src/threading/SerialTypes.cc
+++ b/src/threading/SerialTypes.cc
@@ -12,6 +12,7 @@
 #include "ID.h"
 #include "Expr.h"
 #include "Scope.h"
+#include "IPAddr.h"
 
 using namespace threading;
 
diff --git a/src/zeekygen/ScriptInfo.cc b/src/zeekygen/ScriptInfo.cc
index 827bac5979..ddd0d8009c 100644
--- a/src/zeekygen/ScriptInfo.cc
+++ b/src/zeekygen/ScriptInfo.cc
@@ -10,6 +10,7 @@
 
 #include "Reporter.h"
 #include "Desc.h"
+#include "Type.h"
 
 using namespace std;
 using namespace zeekygen;