diff --git a/js/src/Makefile.in b/js/src/Makefile.in
index 866a926312d..660549200bc 100644
--- a/js/src/Makefile.in
+++ b/js/src/Makefile.in
@@ -29,7 +29,7 @@ endif
 
 DIRS	+=	fdlibm
 
-# DIRS 	+=	xpconnect
+DIRS 	+=	xpconnect
 
 LIBRARY_NAME	= $(MOZ_LIB_JS_PREFIX)js
 
diff --git a/js/src/xpconnect/src/Makefile.in b/js/src/xpconnect/src/Makefile.in
index 405b92ca782..3eec5786621 100644
--- a/js/src/xpconnect/src/Makefile.in
+++ b/js/src/xpconnect/src/Makefile.in
@@ -49,7 +49,5 @@ CPPSRCS=		\
 	xpcwrappednativeclass.cpp	\
 	$(NULL)
 
-export:: libs
-
 include $(topsrcdir)/config/rules.mk
 
diff --git a/xpcom/Makefile.in b/xpcom/Makefile.in
index 4a786c6d30e..a8834e7d86d 100644
--- a/xpcom/Makefile.in
+++ b/xpcom/Makefile.in
@@ -21,7 +21,7 @@ srcdir		= @srcdir@
 
 include $(DEPTH)/config/autoconf.mk
 
-DIRS	= public src idl
+DIRS	= public src idl libxpt
 
 ifdef ENABLE_TESTS
 DIRS += tests
diff --git a/xpcom/libxpt/src/Makefile.in b/xpcom/libxpt/src/Makefile.in
index e3fd3e70d9c..313d259bfd1 100644
--- a/xpcom/libxpt/src/Makefile.in
+++ b/xpcom/libxpt/src/Makefile.in
@@ -30,6 +30,11 @@ CSRCS		= xpt_struct.c 	\
 
 REQUIRES	= $(MODULE)
 
+# build libxpt (but not xptinfo, xptcall subdirs) early so that it'll be
+# available to xpidl, which also must be built early.
 export:: libs
 
 include $(topsrcdir)/config/rules.mk
+
+Move xptinfo, xptcall from export phase (erroneously copied from libxpt Makefile.in) to libs and back out previous temporary fix.
+
diff --git a/xpcom/libxpt/xptcall/src/Makefile.in b/xpcom/libxpt/xptcall/src/Makefile.in
index e2346e13119..22fce155a45 100644
--- a/xpcom/libxpt/xptcall/src/Makefile.in
+++ b/xpcom/libxpt/xptcall/src/Makefile.in
@@ -33,6 +33,6 @@ CSRCS		= xptcall.c 	\
 
 REQUIRES	= $(MODULE)
 
-export:: libs
+# export:: libs
 
 include $(topsrcdir)/config/rules.mk
diff --git a/xpcom/libxpt/xptinfo/src/Makefile.in b/xpcom/libxpt/xptinfo/src/Makefile.in
index 2c4e0df5882..a4b9c3e904a 100644
--- a/xpcom/libxpt/xptinfo/src/Makefile.in
+++ b/xpcom/libxpt/xptinfo/src/Makefile.in
@@ -34,6 +34,6 @@ CPPSRCS		= nsInterfaceInfo.cpp           \
 
 REQUIRES	= $(MODULE)
 
-export:: libs
+# export:: libs
 
 include $(topsrcdir)/config/rules.mk
diff --git a/xpcom/libxpt/xptinfo/src/nsInterfaceInfo.cpp b/xpcom/libxpt/xptinfo/src/nsInterfaceInfo.cpp
index 5f90c59223e..203a665aa28 100644
--- a/xpcom/libxpt/xptinfo/src/nsInterfaceInfo.cpp
+++ b/xpcom/libxpt/xptinfo/src/nsInterfaceInfo.cpp
@@ -18,6 +18,8 @@
 
 /* Implementation of nsIInterfaceInfoManager. */
 
+#include "nscore.h"
+
 #include "nsISupports.h"
 #include "nsIInterfaceInfo.h"
 #include "nsIInterfaceInfoManager.h"
@@ -119,9 +121,9 @@ nsInterfaceInfo::GetMethodInfo(uint16 index, const nsXPTMethodInfo** info)
     }
 
     // else...
-    *info = (nsXPTMethodInfo*) 
-        &mInterfaceRecord->interfaceDescriptor->
-                                method_descriptors[index - mMethodBaseIndex];
+    *info = NS_REINTERPRET_CAST(nsXPTMethodInfo*,
+                                &mInterfaceRecord->interfaceDescriptor->
+                                method_descriptors[index - mMethodBaseIndex]);
     return NS_OK;
 }
 
@@ -131,19 +133,20 @@ nsInterfaceInfo::GetMethodInfoForName(const char* methodName, uint16 *index,
 {
     // XXX probably want to speed this up with a hashtable, or by at least interning
     // the names to avoid the strcmp
+    nsresult rv;
     for (uint16 i = mMethodBaseIndex; i < mMethodCount; i++) {
         const nsXPTMethodInfo* info;
-        info = (nsXPTMethodInfo*)
-                    &mInterfaceRecord->interfaceDescriptor->
-                        method_descriptors[i - mMethodBaseIndex];
+        info = NS_REINTERPRET_CAST(nsXPTMethodInfo*,
+                                   &mInterfaceRecord->interfaceDescriptor->
+                                   method_descriptors[i - mMethodBaseIndex]);
         if (PL_strcmp(methodName, info->name) == 0) {
 #ifdef NS_DEBUG
             // make sure there aren't duplicate names
             for (; i < mMethodCount; i++) {
                 const nsXPTMethodInfo* info2;
-                info2 = (nsXPTMethodInfo*)
-                            &mInterfaceRecord->interfaceDescriptor->
-                                method_descriptors[i - mMethodBaseIndex];
+                info2 = NS_REINTERPRET_CAST(nsXPTMethodInfo*,
+                                           &mInterfaceRecord->interfaceDescriptor->
+                                           method_descriptors[i - mMethodBaseIndex]);
                 NS_ASSERTION(PL_strcmp(methodName, info2->name)!= 0, "duplicate names");
             }
 #endif
@@ -168,9 +171,10 @@ nsInterfaceInfo::GetConstant(uint16 index, const nsXPTConstant** constant)
     }
 
     // else...
-    *constant = (nsXPTConstant*)
-        &mInterfaceRecord->interfaceDescriptor->
-                            const_descriptors[index-mConstantBaseIndex];
+    *constant =
+        NS_REINTERPRET_CAST(nsXPTConstant*,
+                            &mInterfaceRecord->interfaceDescriptor->
+                            const_descriptors[index-mConstantBaseIndex]);
     return NS_OK;
 }
 
diff --git a/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.cpp b/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.cpp
index ef8e80d85bc..568dd567946 100644
--- a/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.cpp
+++ b/xpcom/libxpt/xptinfo/src/nsInterfaceInfoManager.cpp
@@ -19,6 +19,7 @@
 /* Implementation of nsIInterfaceInfo. */
 
 #include <sys/stat.h>
+#include "nscore.h"
 
 #include "nsISupports.h"
 #include "nsIInterfaceInfoManager.h"
diff --git a/xpcom/reflect/xptcall/src/Makefile.in b/xpcom/reflect/xptcall/src/Makefile.in
index e2346e13119..22fce155a45 100644
--- a/xpcom/reflect/xptcall/src/Makefile.in
+++ b/xpcom/reflect/xptcall/src/Makefile.in
@@ -33,6 +33,6 @@ CSRCS		= xptcall.c 	\
 
 REQUIRES	= $(MODULE)
 
-export:: libs
+# export:: libs
 
 include $(topsrcdir)/config/rules.mk
diff --git a/xpcom/reflect/xptinfo/src/Makefile.in b/xpcom/reflect/xptinfo/src/Makefile.in
index 2c4e0df5882..a4b9c3e904a 100644
--- a/xpcom/reflect/xptinfo/src/Makefile.in
+++ b/xpcom/reflect/xptinfo/src/Makefile.in
@@ -34,6 +34,6 @@ CPPSRCS		= nsInterfaceInfo.cpp           \
 
 REQUIRES	= $(MODULE)
 
-export:: libs
+# export:: libs
 
 include $(topsrcdir)/config/rules.mk
diff --git a/xpcom/reflect/xptinfo/src/nsInterfaceInfo.cpp b/xpcom/reflect/xptinfo/src/nsInterfaceInfo.cpp
index 5f90c59223e..203a665aa28 100644
--- a/xpcom/reflect/xptinfo/src/nsInterfaceInfo.cpp
+++ b/xpcom/reflect/xptinfo/src/nsInterfaceInfo.cpp
@@ -18,6 +18,8 @@
 
 /* Implementation of nsIInterfaceInfoManager. */
 
+#include "nscore.h"
+
 #include "nsISupports.h"
 #include "nsIInterfaceInfo.h"
 #include "nsIInterfaceInfoManager.h"
@@ -119,9 +121,9 @@ nsInterfaceInfo::GetMethodInfo(uint16 index, const nsXPTMethodInfo** info)
     }
 
     // else...
-    *info = (nsXPTMethodInfo*) 
-        &mInterfaceRecord->interfaceDescriptor->
-                                method_descriptors[index - mMethodBaseIndex];
+    *info = NS_REINTERPRET_CAST(nsXPTMethodInfo*,
+                                &mInterfaceRecord->interfaceDescriptor->
+                                method_descriptors[index - mMethodBaseIndex]);
     return NS_OK;
 }
 
@@ -131,19 +133,20 @@ nsInterfaceInfo::GetMethodInfoForName(const char* methodName, uint16 *index,
 {
     // XXX probably want to speed this up with a hashtable, or by at least interning
     // the names to avoid the strcmp
+    nsresult rv;
     for (uint16 i = mMethodBaseIndex; i < mMethodCount; i++) {
         const nsXPTMethodInfo* info;
-        info = (nsXPTMethodInfo*)
-                    &mInterfaceRecord->interfaceDescriptor->
-                        method_descriptors[i - mMethodBaseIndex];
+        info = NS_REINTERPRET_CAST(nsXPTMethodInfo*,
+                                   &mInterfaceRecord->interfaceDescriptor->
+                                   method_descriptors[i - mMethodBaseIndex]);
         if (PL_strcmp(methodName, info->name) == 0) {
 #ifdef NS_DEBUG
             // make sure there aren't duplicate names
             for (; i < mMethodCount; i++) {
                 const nsXPTMethodInfo* info2;
-                info2 = (nsXPTMethodInfo*)
-                            &mInterfaceRecord->interfaceDescriptor->
-                                method_descriptors[i - mMethodBaseIndex];
+                info2 = NS_REINTERPRET_CAST(nsXPTMethodInfo*,
+                                           &mInterfaceRecord->interfaceDescriptor->
+                                           method_descriptors[i - mMethodBaseIndex]);
                 NS_ASSERTION(PL_strcmp(methodName, info2->name)!= 0, "duplicate names");
             }
 #endif
@@ -168,9 +171,10 @@ nsInterfaceInfo::GetConstant(uint16 index, const nsXPTConstant** constant)
     }
 
     // else...
-    *constant = (nsXPTConstant*)
-        &mInterfaceRecord->interfaceDescriptor->
-                            const_descriptors[index-mConstantBaseIndex];
+    *constant =
+        NS_REINTERPRET_CAST(nsXPTConstant*,
+                            &mInterfaceRecord->interfaceDescriptor->
+                            const_descriptors[index-mConstantBaseIndex]);
     return NS_OK;
 }
 
diff --git a/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.cpp b/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.cpp
index ef8e80d85bc..568dd567946 100644
--- a/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.cpp
+++ b/xpcom/reflect/xptinfo/src/nsInterfaceInfoManager.cpp
@@ -19,6 +19,7 @@
 /* Implementation of nsIInterfaceInfo. */
 
 #include <sys/stat.h>
+#include "nscore.h"
 
 #include "nsISupports.h"
 #include "nsIInterfaceInfoManager.h"
diff --git a/xpcom/typelib/xpt/src/Makefile.in b/xpcom/typelib/xpt/src/Makefile.in
index e3fd3e70d9c..313d259bfd1 100644
--- a/xpcom/typelib/xpt/src/Makefile.in
+++ b/xpcom/typelib/xpt/src/Makefile.in
@@ -30,6 +30,11 @@ CSRCS		= xpt_struct.c 	\
 
 REQUIRES	= $(MODULE)
 
+# build libxpt (but not xptinfo, xptcall subdirs) early so that it'll be
+# available to xpidl, which also must be built early.
 export:: libs
 
 include $(topsrcdir)/config/rules.mk
+
+Move xptinfo, xptcall from export phase (erroneously copied from libxpt Makefile.in) to libs and back out previous temporary fix.
+