diff --git a/Changes b/Changes
index db95bdbfc..75d435268 100644
--- a/Changes
+++ b/Changes
@@ -15,6 +15,8 @@ indicates the contributor was also the author of the fix; Thanks!
 
 ****  Fix duplicate begin error broke in 3.840, bug548.  [Alex Solomatnikov]
 
+****  Fix triangle symbol resolution error broke in 3.840, bug550.  [Ted Campbell]
+
 
 * Verilator 3.840 2012/07/31 Beta
 
diff --git a/src/V3LinkCells.cpp b/src/V3LinkCells.cpp
index af5a9731e..ddd0cb6e4 100644
--- a/src/V3LinkCells.cpp
+++ b/src/V3LinkCells.cpp
@@ -96,6 +96,7 @@ private:
 
     // STATE
     V3InFilter*		m_filterp;	// Parser filter
+    V3ParseSym*		m_parseSymp;	// Parser symbol table
 
     // Below state needs to be preserved between each module call.
     AstNodeModule*	m_modp;		// Current module
@@ -202,7 +203,7 @@ private:
 		// Read-subfile
 		// If file not found, make AstNotFoundModule, rather than error out.
 		// We'll throw the error when we know the module will really be needed.
-		V3Parse parser (v3Global.rootp(), m_filterp);
+		V3Parse parser (v3Global.rootp(), m_filterp, m_parseSymp);
 		parser.parseFile(nodep->fileline(), nodep->modName(), false, "");
 		V3Error::abortIfErrors();
 		// We've read new modules, grab new pointers to their names
@@ -284,6 +285,7 @@ private:
 	if (nodep->modp()) {
 	    nodep->iterateChildren(*this);
 	}
+	UINFO(4," Link Cell done: "<<nodep<<endl);
     }
 
     // Accelerate the recursion
@@ -316,9 +318,10 @@ private:
 
 public:
     // CONSTUCTORS
-    LinkCellsVisitor(AstNetlist* rootp, V3InFilter* filterp)
+    LinkCellsVisitor(AstNetlist* rootp, V3InFilter* filterp, V3ParseSym* parseSymp)
 	: m_mods(rootp) {
 	m_filterp = filterp;
+	m_parseSymp = parseSymp;
 	m_modp = NULL;
 	m_libVertexp = NULL;
 	m_topVertexp = NULL;
@@ -330,7 +333,7 @@ public:
 //######################################################################
 // Link class functions
 
-void V3LinkCells::link(AstNetlist* rootp, V3InFilter* filterp) {
+void V3LinkCells::link(AstNetlist* rootp, V3InFilter* filterp, V3ParseSym* parseSymp) {
     UINFO(4,__FUNCTION__<<": "<<endl);
-    LinkCellsVisitor visitor (rootp, filterp);
+    LinkCellsVisitor visitor (rootp, filterp, parseSymp);
 }
diff --git a/src/V3LinkCells.h b/src/V3LinkCells.h
index ef3dd859c..8e68479d3 100644
--- a/src/V3LinkCells.h
+++ b/src/V3LinkCells.h
@@ -26,12 +26,13 @@
 #include "V3Ast.h"
 
 class V3InFilter;
+class V3ParseSym;
 
 //============================================================================
 
 class V3LinkCells {
 public:
-    static void link(AstNetlist* nodep, V3InFilter* filterp);
+    static void link(AstNetlist* nodep, V3InFilter* filterp, V3ParseSym* parseSymp);
 };
 
 #endif // Guard
diff --git a/src/V3Parse.h b/src/V3Parse.h
index 256d67a99..85b25be56 100644
--- a/src/V3Parse.h
+++ b/src/V3Parse.h
@@ -28,6 +28,7 @@
 class AstNetlist;
 class V3InFilter;
 class V3ParseImp;
+class V3ParseSym;
 
 //============================================================================
 
@@ -38,7 +39,7 @@ private:
 public:
     // CONSTRUCTORS
     // We must allow reading multiple files into one parser
-    V3Parse(AstNetlist* rootp, V3InFilter* filterp);
+    V3Parse(AstNetlist* rootp, V3InFilter* filterp, V3ParseSym* symp);
     ~V3Parse();
 
     // METHODS
diff --git a/src/V3ParseImp.cpp b/src/V3ParseImp.cpp
index 69ea5350b..9647e101d 100644
--- a/src/V3ParseImp.cpp
+++ b/src/V3ParseImp.cpp
@@ -159,8 +159,8 @@ void V3ParseImp::lexFile(const string& modname) {
 //======================================================================
 // V3Parse functions
 
-V3Parse::V3Parse(AstNetlist* rootp, V3InFilter* filterp) {
-    m_impp = new V3ParseImp (rootp, filterp);
+V3Parse::V3Parse(AstNetlist* rootp, V3InFilter* filterp, V3ParseSym* symp) {
+    m_impp = new V3ParseImp (rootp, filterp, symp);
 }
 V3Parse::~V3Parse() {
     delete m_impp; m_impp = NULL;
diff --git a/src/V3ParseImp.h b/src/V3ParseImp.h
index 4f6169d1f..43dcd3a12 100644
--- a/src/V3ParseImp.h
+++ b/src/V3ParseImp.h
@@ -92,11 +92,12 @@ class V3ParseImp {
     // MEMBERS
     AstNetlist* 	m_rootp;	// Root of the design
     V3InFilter*		m_filterp;	// Reading filter
+    V3ParseSym*		m_symp;		// Symbol table
+
     V3Lexer*		m_lexerp;	// Current FlexLexer
     static V3ParseImp*	s_parsep;	// Current THIS, bison() isn't class based
     FileLine*		m_fileline;	// Filename/linenumber currently active
 
-    V3ParseSym	m_sym;			// Symbol table
     bool	m_inCellDefine;		// Inside a `celldefine
     bool	m_inLibrary;		// Currently reading a library vs. regular file
     int		m_inBeginKwd;		// Inside a `begin_keywords
@@ -193,14 +194,14 @@ public:
     size_t flexPpInputToLex(char* buf, size_t max_size) { return ppInputToLex(buf,max_size); }
 
     //==== Symbol tables
-    V3ParseSym* symp() { return &m_sym; }
+    V3ParseSym* symp() { return m_symp; }
 
 public:
     // CREATORS
-    V3ParseImp(AstNetlist* rootp, V3InFilter* filterp)
-	: m_filterp(filterp), m_sym(rootp) {
+    V3ParseImp(AstNetlist* rootp, V3InFilter* filterp, V3ParseSym* parserSymp)
+	: m_rootp(rootp), m_filterp(filterp), m_symp(parserSymp) {
 	m_fileline = NULL;
-	m_rootp = rootp; m_lexerp = NULL;
+	m_lexerp = NULL;
 	m_inCellDefine = false;
 	m_inLibrary = false;
 	m_inBeginKwd = 0;
diff --git a/src/V3SymTable.h b/src/V3SymTable.h
index f86b02b56..bf395ce9e 100644
--- a/src/V3SymTable.h
+++ b/src/V3SymTable.h
@@ -53,7 +53,7 @@ private:
     VSymEnt*	m_parentp;	// Table that created this table, dot notation needed to resolve into it
     AstPackage*	m_packagep;	// Package node is in (for V3LinkDot, unused here)
     string	m_symPrefix;	// String to prefix symbols with (for V3LinkDot, unused here)
-#if 0 // debug
+#ifdef VL_DEBUG
     static int debug() {
 	static int level = -1;
 	if (VL_UNLIKELY(level < 0)) level = v3Global.opt.debugSrcLevel("V3LinkDot.cpp");
@@ -87,7 +87,18 @@ public:
 
     // METHODS
     VSymEnt(VSymGraph* graphp, AstNode* nodep);  // Below
-    ~VSymEnt() {}
+    ~VSymEnt() {
+	// Change links so we coredump if used
+#ifdef VL_DEBUG
+	m_nodep = (AstNode*)1;
+	m_fallbackp = (VSymEnt*)1;
+	m_parentp = (VSymEnt*)1;
+	m_packagep = (AstPackage*)1;
+#endif
+    }
+#if defined(VL_DEBUG) && !defined(VL_LEAK_CHECKS)
+    void operator delete(void* objp, size_t size) {} // For testing, leak so above destructor 1 assignments work
+#endif
     void fallbackp(VSymEnt* entp) { m_fallbackp = entp; }
     void parentp(VSymEnt* entp) { m_parentp = entp; }
     VSymEnt* parentp() const { return m_parentp; }
diff --git a/src/Verilator.cpp b/src/Verilator.cpp
index c4c583b75..97bd7cc5e 100644
--- a/src/Verilator.cpp
+++ b/src/Verilator.cpp
@@ -70,6 +70,7 @@
 #include "V3Order.h"
 #include "V3Param.h"
 #include "V3Parse.h"
+#include "V3ParseSym.h"
 #include "V3PreShell.h"
 #include "V3Premit.h"
 #include "V3Scope.h"
@@ -111,8 +112,9 @@ void V3Global::readFiles() {
     AstUser4InUse	inuser4;
 
     V3InFilter filter (v3Global.opt.pipeFilter());
+    V3ParseSym parseSyms (v3Global.rootp());  // Symbol table must be common across all parsing
 
-    V3Parse parser (v3Global.rootp(), &filter);
+    V3Parse parser (v3Global.rootp(), &filter, &parseSyms);
     // Read top module
     for (V3StringList::const_iterator it = v3Global.opt.vFiles().begin();
 	 it != v3Global.opt.vFiles().end(); ++it) {
@@ -135,7 +137,7 @@ void V3Global::readFiles() {
 
     if (!v3Global.opt.preprocOnly()) {
 	// Resolve all modules cells refer to
-	V3LinkCells::link(v3Global.rootp(), &filter);
+	V3LinkCells::link(v3Global.rootp(), &filter, &parseSyms);
     }
 }