diff --git a/src/V3Ast.cpp b/src/V3Ast.cpp
index 30dd5322c..78e29bdbe 100644
--- a/src/V3Ast.cpp
+++ b/src/V3Ast.cpp
@@ -1171,6 +1171,31 @@ void AstNode::checkTreeIter(const AstNode* prevBackp) const VL_MT_STABLE {
         default: this->v3fatalSrc("Bad case"); break;
         }
     }
+    if (v3Global.opt.debugWidth() && v3Global.widthMinUsage() == VWidthMinUsage::VERILOG_WIDTH) {
+        if (const AstNodeExpr* const exprp = VN_CAST(this, NodeExpr)) {
+            const char* const whyp = exprp->widthMismatch();
+            if (whyp) {
+                auto dtypeStr = [](const AstNodeExpr* exprp) VL_MT_STABLE {
+                    std::ostringstream ss;
+                    exprp->dtypep()->dumpSmall(ss);
+                    return ss.str();
+                };
+                if (const AstNodeUniop* const uniopp = VN_CAST(exprp, NodeUniop)) {
+                    UASSERT_OBJ(!whyp, uniopp,
+                                "widthMismatch detected " << whyp << "OUT:" << dtypeStr(uniopp)
+                                                          << " LHS:" << dtypeStr(uniopp->lhsp()));
+                } else if (const AstNodeBiop* const biopp = VN_CAST(exprp, NodeBiop)) {
+                    UASSERT_OBJ(!whyp, biopp,
+                                "widthMismatch detected " << whyp << "OUT:" << dtypeStr(biopp)
+                                                          << " LHS:" << dtypeStr(biopp->lhsp())
+                                                          << " RHS:" << dtypeStr(biopp->rhsp()));
+                } else {
+                    UASSERT_OBJ(false, exprp,
+                                "widthMismatch detected " << whyp << " in an unexpected type");
+                }
+            }
+        }
+    }
 }
 
 // cppcheck-suppress unusedFunction  // Debug only
diff --git a/src/V3Ast.h b/src/V3Ast.h
index 0c8227236..86b1c266f 100644
--- a/src/V3Ast.h
+++ b/src/V3Ast.h
@@ -2002,7 +2002,7 @@ public:
 
     // TODO stomp these width functions out, and call via dtypep() instead
     inline int width() const VL_MT_STABLE;
-    inline int widthMin() const;
+    inline int widthMin() const VL_MT_STABLE;
     int widthMinV() const {
         return v3Global.widthMinUsage() == VWidthMinUsage::VERILOG_WIDTH ? widthMin() : width();
     }
diff --git a/src/V3AstInlines.h b/src/V3AstInlines.h
index 9e61a7740..8a1e1f96f 100644
--- a/src/V3AstInlines.h
+++ b/src/V3AstInlines.h
@@ -26,7 +26,7 @@
 // Inline METHODS
 
 int AstNode::width() const VL_MT_STABLE { return dtypep() ? dtypep()->width() : 0; }
-int AstNode::widthMin() const { return dtypep() ? dtypep()->widthMin() : 0; }
+int AstNode::widthMin() const VL_MT_STABLE { return dtypep() ? dtypep()->widthMin() : 0; }
 bool AstNode::width1() const {  // V3Const uses to know it can optimize
     return dtypep() && dtypep()->width() == 1;
 }
diff --git a/src/V3AstNodeDType.h b/src/V3AstNodeDType.h
index 56e2c014f..b6457f9f3 100644
--- a/src/V3AstNodeDType.h
+++ b/src/V3AstNodeDType.h
@@ -53,7 +53,7 @@ public:
     // ACCESSORS
     void dump(std::ostream& str) const override;
     void dumpJson(std::ostream& str) const override;
-    virtual void dumpSmall(std::ostream& str) const;
+    virtual void dumpSmall(std::ostream& str) const VL_MT_STABLE;
     bool hasDType() const override { return true; }
     /// Require VlUnpacked, instead of [] for POD elements.
     /// A non-POD object is always compound, but some POD elements
diff --git a/src/V3AstNodeExpr.h b/src/V3AstNodeExpr.h
index 5c23b9fac..dcebf3f3d 100644
--- a/src/V3AstNodeExpr.h
+++ b/src/V3AstNodeExpr.h
@@ -65,6 +65,9 @@ public:
 
     // Wrap This expression into an AstStmtExpr to denote it occurs in statement position
     inline AstStmtExpr* makeStmt();
+    // Returns an error message if widthMin() is not correct otherwise returns nullptr like
+    // broken()
+    virtual const char* widthMismatch() const VL_MT_STABLE { return nullptr; }
 };
 class AstNodeBiop VL_NOT_FINAL : public AstNodeExpr {
     // Binary expression
@@ -3830,6 +3833,7 @@ public:
     bool cleanRhs() const override { return false; }
     bool sizeMattersLhs() const override { return false; }
     bool sizeMattersRhs() const override { return false; }
+    const char* widthMismatch() const override VL_MT_STABLE;
 };
 class AstMul final : public AstNodeBiComAsv {
 public:
@@ -3924,6 +3928,7 @@ public:
     bool cleanRhs() const override { return false; }
     bool sizeMattersLhs() const override { return false; }
     bool sizeMattersRhs() const override { return false; }
+    const char* widthMismatch() const override VL_MT_STABLE;
 };
 class AstXor final : public AstNodeBiComAsv {
 public:
@@ -3946,6 +3951,7 @@ public:
     bool cleanRhs() const override { return false; }
     bool sizeMattersLhs() const override { return false; }
     bool sizeMattersRhs() const override { return false; }
+    const char* widthMismatch() const override VL_MT_STABLE;
 };
 
 // === AstNodeDistBiop ===
@@ -5082,6 +5088,7 @@ public:
     bool cleanOut() const override { return false; }
     bool cleanLhs() const override { return false; }
     bool sizeMattersLhs() const override { return true; }
+    const char* widthMismatch() const override VL_MT_STABLE;
 };
 class AstNullCheck final : public AstNodeUniop {
     // Return LHS after checking that LHS is non-null
diff --git a/src/V3AstNodes.cpp b/src/V3AstNodes.cpp
index b6c3aa1bf..5c269915f 100644
--- a/src/V3AstNodes.cpp
+++ b/src/V3AstNodes.cpp
@@ -1916,7 +1916,7 @@ void AstNodeDType::dumpJson(std::ostream& str) const {
     dumpJsonBoolFunc(str, generic);
     dumpJsonGen(str);
 }
-void AstNodeDType::dumpSmall(std::ostream& str) const {
+void AstNodeDType::dumpSmall(std::ostream& str) const VL_MT_STABLE {
     str << "(" << (generic() ? "G/" : "") << ((isSigned() && !isDouble()) ? "s" : "")
         << (isNosign() ? "n" : "") << (isDouble() ? "d" : "") << (isString() ? "str" : "");
     if (!isDouble() && !isString()) str << "w" << (widthSized() ? "" : "u") << width();
@@ -2757,3 +2757,22 @@ void AstDelay::dumpJson(std::ostream& str) const {
     dumpJsonBoolFunc(str, isCycleDelay);
     dumpJsonGen(str);
 }
+const char* AstAnd::widthMismatch() const VL_MT_STABLE {
+    BROKEN_RTN(lhsp()->widthMin() != rhsp()->widthMin());
+    BROKEN_RTN(lhsp()->widthMin() != widthMin());
+    return nullptr;
+}
+const char* AstOr::widthMismatch() const VL_MT_STABLE {
+    BROKEN_RTN(lhsp()->widthMin() != rhsp()->widthMin());
+    BROKEN_RTN(lhsp()->widthMin() != widthMin());
+    return nullptr;
+}
+const char* AstXor::widthMismatch() const VL_MT_STABLE {
+    BROKEN_RTN(lhsp()->widthMin() != rhsp()->widthMin());
+    BROKEN_RTN(lhsp()->widthMin() != widthMin());
+    return nullptr;
+}
+const char* AstNot::widthMismatch() const VL_MT_STABLE {
+    BROKEN_RTN(lhsp()->widthMin() != widthMin());
+    return nullptr;
+}
diff --git a/src/V3Global.h b/src/V3Global.h
index 1c387ab60..8fcb31582 100644
--- a/src/V3Global.h
+++ b/src/V3Global.h
@@ -75,16 +75,17 @@ public:
     VWidthMinUsage()
         : m_e{LINT_WIDTH} {}
     // cppcheck-suppress noExplicitConstructor
-    constexpr VWidthMinUsage(en _e)
-        : m_e{_e} {}
+    constexpr VWidthMinUsage(en _e) VL_PURE : m_e{_e} {}
+    constexpr VWidthMinUsage(const VWidthMinUsage& _e) VL_PURE = default;
     explicit VWidthMinUsage(int _e)
         : m_e(static_cast<en>(_e)) {}  // Need () or GCC 4.8 false warning
     constexpr operator en() const { return m_e; }
+    constexpr VWidthMinUsage& operator=(const VWidthMinUsage& _e) VL_PURE = default;
 };
 constexpr bool operator==(const VWidthMinUsage& lhs, const VWidthMinUsage& rhs) {
     return lhs.m_e == rhs.m_e;
 }
-constexpr bool operator==(const VWidthMinUsage& lhs, VWidthMinUsage::en rhs) {
+constexpr bool operator==(const VWidthMinUsage& lhs, VWidthMinUsage::en rhs) VL_PURE {
     return lhs.m_e == rhs;
 }
 constexpr bool operator==(VWidthMinUsage::en lhs, const VWidthMinUsage& rhs) {
@@ -140,7 +141,7 @@ public:
 
     // ACCESSORS (general)
     AstNetlist* rootp() const VL_MT_SAFE { return m_rootp; }
-    VWidthMinUsage widthMinUsage() const { return m_widthMinUsage; }
+    VWidthMinUsage widthMinUsage() const VL_PURE { return m_widthMinUsage; }
     bool assertDTypesResolved() const { return m_assertDTypesResolved; }
     bool assertScoped() const { return m_assertScoped; }
 
diff --git a/src/V3Options.cpp b/src/V3Options.cpp
index fc47d3cbd..f0daaef6c 100644
--- a/src/V3Options.cpp
+++ b/src/V3Options.cpp
@@ -1197,6 +1197,7 @@ void V3Options::parseOptsList(FileLine* fl, const string& optdir, int argc,
     DECL_OPTION("-debug-self-test", OnOff, &m_debugSelfTest).undocumented();
     DECL_OPTION("-debug-sigsegv", CbCall, throwSigsegv).undocumented();  // See also --debug-abort
     DECL_OPTION("-debug-stack-check", OnOff, &m_debugStackCheck).undocumented();
+    DECL_OPTION("-debug-width", OnOff, &m_debugWidth).undocumented();
     DECL_OPTION("-decoration", CbCall, [this, fl]() { decorations(fl, "medium"); });
     DECL_OPTION("-decorations", CbVal, [this, fl](const char* optp) { decorations(fl, optp); });
     DECL_OPTION("-no-decoration", CbCall, [this, fl]() { decorations(fl, "none"); });
diff --git a/src/V3Options.h b/src/V3Options.h
index 99ba731d1..ef0a7b627 100644
--- a/src/V3Options.h
+++ b/src/V3Options.h
@@ -245,6 +245,7 @@ private:
     bool m_debugProtect = false;    // main switch: --debug-protect
     bool m_debugSelfTest = false;   // main switch: --debug-self-test
     bool m_debugStackCheck = false;  // main switch: --debug-stack-check
+    bool m_debugWidth = false;      // main switch: --debug-width
     bool m_decoration = true;       // main switch: --decoration
     bool m_decorationNodes = false;  // main switch: --decoration=nodes
     bool m_dpiHdrOnly = false;      // main switch: --dpi-hdr-only
@@ -483,6 +484,7 @@ public:
     bool debugProtect() const VL_MT_SAFE { return m_debugProtect; }
     bool debugSelfTest() const { return m_debugSelfTest; }
     bool debugStackCheck() const { return m_debugStackCheck; }
+    bool debugWidth() const VL_PURE { return m_debugWidth; }
     bool decoration() const VL_MT_SAFE { return m_decoration; }
     bool decorationNodes() const VL_MT_SAFE { return m_decorationNodes; }
     bool dpiHdrOnly() const { return m_dpiHdrOnly; }
diff --git a/test_regress/t/t_debug_width.out b/test_regress/t/t_debug_width.out
new file mode 100644
index 000000000..0a1f7b907
--- /dev/null
+++ b/test_regress/t/t_debug_width.out
@@ -0,0 +1,4 @@
+%Error: Internal Error: t/t_const_opt.v:531:34: ../V3Ast.cpp:#: widthMismatch detected 'lhsp()->widthMin() != rhsp()->widthMin()' @ ../V3AstNodes.cpp:#OUT:(G/wu32/1) LHS:(G/w32) RHS:(G/wu32/1)
+  531 |    always_ff @(posedge clkin_data[0], posedge myfirst, posedge mysecond)
+      |                                  ^
+                        ... See the manual at https://verilator.org/verilator_doc.html for more assistance.
diff --git a/test_regress/t/t_debug_width.pl b/test_regress/t/t_debug_width.pl
new file mode 100755
index 000000000..b4ae3a10c
--- /dev/null
+++ b/test_regress/t/t_debug_width.pl
@@ -0,0 +1,21 @@
+#!/usr/bin/env perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+top_filename("t/t_const_opt.v");
+scenarios(simulator => 1);
+
+lint(
+    verilator_flags2 => ["--lint-only", "--debug-width"],
+    fails => 1,
+    expect_filename => $Self->{golden_filename},
+    );
+
+ok(1);
+1;