diff --git a/Changes b/Changes
index 4a99d0189..21cb7b1d3 100644
--- a/Changes
+++ b/Changes
@@ -3,7 +3,10 @@ Revision history for Verilator
 The contributors that suggested a given feature are shown in []. Thanks!
 
 
-* Verilator 4.027 devel
+* Verilator 4.029 devel
+
+
+* Verilator 4.028 2020-02-08
 
 **    Support attributes (public, isolate_assignments, etc.) in configuration files.
 
@@ -25,6 +28,8 @@ The contributors that suggested a given feature are shown in []. Thanks!
 
 ****  Support enum.next(k) with constant k > 1, #2125. [Tobias Rosenkranz]
 
+****  Support parameter access from arrays of interfaces, #2155. [Todd Strader]
+
 ****  Add parameter values in XML. #2110. [Pieter Kapsenberg]
 
 ****  Add loc column location in XML (replaces fl), #2122. [Pieter Kapsenberg]
@@ -41,6 +46,8 @@ The contributors that suggested a given feature are shown in []. Thanks!
 
 ****  Fix WIDTH warning on </<= of narrower value, #2141. [agrobman]
 
+****  Fix OpenSolaris issues, #2154. [brancoliticus]
+
 
 * Verilator 4.026 2020-01-11
 
@@ -168,10 +175,10 @@ The contributors that suggested a given feature are shown in []. Thanks!
 
 * Verilator 4.020 2019-10-06
 
-***   Support $fseek, $ftell, $frewind, #1496. [Howard Su]
-
 ***   Add --public-flat-rw, #1511. [Stefan Wallentowitz]
 
+***   Support $fseek, $ftell, $frewind, #1496. [Howard Su]
+
 ***   Support vpiModule, #1469. [Stefan Wallentowitz]
 
 ****  Make Syms file honor --output-split-cfuncs, #1499. [Todd Strader]
@@ -192,6 +199,8 @@ The contributors that suggested a given feature are shown in []. Thanks!
 
 ****  Fix case statements with strings, #1536. [Philipp Wagner]
 
+****  Fix some coverage lost when multithreaded, #2151.
+
 
 * Verilator 4.018 2019-08-29
 
diff --git a/MANIFEST.SKIP b/MANIFEST.SKIP
index 2a964c31b..c0d696663 100644
--- a/MANIFEST.SKIP
+++ b/MANIFEST.SKIP
@@ -19,14 +19,15 @@
 \.codacy\.yml
 \.travis\.yml
 /build/
-/obj_dir/
 /obj_dbg/
+/obj_dir/
+/obj_dist/
+/obj_iv/
 /obj_nc/
 /obj_opt/
 /obj_vcs/
 /obj_vlt/
 /obj_vltmt/
-/obj_dist/
 /INCA_libs/
 /cov_work/
 /logs/
diff --git a/configure.ac b/configure.ac
index 51eec8f82..51bb7b2a0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -6,7 +6,7 @@
 
 #AC_INIT([Verilator],[#.### YYYY-MM-DD])
 #AC_INIT([Verilator],[#.### devel])
-AC_INIT([Verilator],[4.027 devel],
+AC_INIT([Verilator],[4.029 devel],
         [https://verilator.org],
         [verilator],[https://verilator.org])
 # When releasing, also update header of Changes file
diff --git a/include/verilated.cpp b/include/verilated.cpp
index b9b408b60..980a5980c 100644
--- a/include/verilated.cpp
+++ b/include/verilated.cpp
@@ -1832,7 +1832,7 @@ void VL_READMEM_N(bool hex,  // Hex format, else binary
                   QData end  // Last row address to read
                   ) VL_MT_SAFE {
     QData addr_max = array_lsb + depth - 1;
-    if (start < array_lsb) start = array_lsb;
+    if (start < static_cast<QData>(array_lsb)) start = array_lsb;
     QData addr_end = end;
     if (addr_end > addr_max) addr_end = addr_max;
 
@@ -1883,7 +1883,7 @@ void VL_WRITEMEM_N(bool hex,  // Hex format, else binary
                    QData end  // Last address to write, or ~0 when not specified
                    ) VL_MT_SAFE {
     QData addr_max = array_lsb + depth - 1;
-    if (start < array_lsb) start = array_lsb;
+    if (start < static_cast<QData>(array_lsb)) start = array_lsb;
     if (end > addr_max) end = addr_max;
 
     VlWriteMem wmem(hex, bits, filename, start, end);
@@ -2396,9 +2396,9 @@ VerilatedVar* VerilatedScope::varFind(const char* namep) const VL_MT_SAFE_POSTIN
 
 void* VerilatedScope::exportFindNullError(int funcnum) VL_MT_SAFE {
     // Slowpath - Called only when find has failed
-    std::string msg = (std::string("Testbench C called '")
-                       +VerilatedImp::exportName(funcnum)
-                       +"' but scope wasn't set, perhaps due to dpi import call without 'context'");
+    std::string msg = (std::string("Testbench C called '") + VerilatedImp::exportName(funcnum)
+                       + "' but scope wasn't set, perhaps due to dpi import call without "
+                       + "'context', or missing svSetScope. See IEEE 1800-2017 35.5.3.");
     VL_FATAL_MT("unknown", 0, "", msg.c_str());
     return NULL;
 }
diff --git a/include/verilated_fst_c.cpp b/include/verilated_fst_c.cpp
index 976e171e7..2e2533cbc 100644
--- a/include/verilated_fst_c.cpp
+++ b/include/verilated_fst_c.cpp
@@ -20,6 +20,7 @@
 //=============================================================================
 // SPDIFF_OFF
 
+#define __STDC_LIMIT_MACROS  // UINT64_MAX
 #include "verilatedos.h"
 #include "verilated.h"
 #include "verilated_fst_c.h"
@@ -47,6 +48,7 @@
 #if defined(_WIN32) && !defined(__MINGW32__) && !defined(__CYGWIN__)
 # include <io.h>
 #else
+# include <stdint.h>
 # include <unistd.h>
 #endif
 
diff --git a/include/verilated_vpi.cpp b/include/verilated_vpi.cpp
index 1de5908c0..d22c1c807 100644
--- a/include/verilated_vpi.cpp
+++ b/include/verilated_vpi.cpp
@@ -1993,7 +1993,7 @@ PLI_INT32 vpi_chk_error(p_vpi_error_info error_info_p) {
     }
     if (!_error_info_p) return 0;  // no error occured
     return _error_info_p->level;  // return error severity level
-};
+}
 
 PLI_INT32 vpi_free_object(vpiHandle object) {
     VerilatedVpiImp::assertOneCheck();
diff --git a/src/V3Ast.h b/src/V3Ast.h
index 79fc039df..4af07e190 100644
--- a/src/V3Ast.h
+++ b/src/V3Ast.h
@@ -111,7 +111,7 @@ public:
             "UNSIGNED", "SIGNED", "NOSIGN"
         };
         return names[m_e];
-    };
+    }
     inline AstNumeric() : m_e(UNSIGNED) {}
     // cppcheck-suppress noExplicitConstructor
     inline AstNumeric(en _e) : m_e(_e) {}
@@ -346,7 +346,7 @@ public:
             "VAR_NO_CLOCKER"
         };
         return names[m_e];
-    };
+    }
     inline AstAttrType() : m_e(ILLEGAL) {}
     // cppcheck-suppress noExplicitConstructor
     inline AstAttrType(en _e) : m_e(_e) {}
@@ -391,7 +391,7 @@ public:
             " MAX"
         };
         return names[m_e];
-    };
+    }
     const char* dpiType() const {
         static const char* const names[] = {
             "%E-unk",
@@ -404,7 +404,7 @@ public:
             " MAX"
         };
         return names[m_e];
-    };
+    }
     static void selfTest() {
         UASSERT(0==strcmp(AstBasicDTypeKwd(_ENUM_MAX).ascii(), " MAX"), "SelfTest: Enum mismatch");
         UASSERT(0==strcmp(AstBasicDTypeKwd(_ENUM_MAX).dpiType(), " MAX"), "SelfTest: Enum mismatch");
@@ -1025,14 +1025,14 @@ protected:
         clearcnt(id, cntGblRef, userBusyRef);  // Includes a checkUse for us
         userBusyRef = false;
     }
-    static void clearcnt(int id, uint32_t& cntGblRef, bool& userBusyRef) {
+    static void clearcnt(int id, uint32_t& cntGblRef, const bool& userBusyRef) {
         UASSERT_STATIC(userBusyRef, "Clear of User"+cvtToStr(id)+"() not under AstUserInUse");
         // If this really fires and is real (after 2^32 edits???)
         // we could just walk the tree and clear manually
         ++cntGblRef;
         UASSERT_STATIC(cntGblRef, "User*() overflowed!");
     }
-    static void checkcnt(int id, uint32_t&, bool& userBusyRef) {
+    static void checkcnt(int id, uint32_t&, const bool& userBusyRef) {
         UASSERT_STATIC(userBusyRef, "Check of User"+cvtToStr(id)+"() failed, not under AstUserInUse");
     }
 };
@@ -1197,7 +1197,7 @@ public:
     explicit V3Hash(VNUser u) { m_both = u.toInt(); }
     V3Hash operator+= (const V3Hash& rh) {
         setBoth(depth()+rh.depth(), (hshval()*31+rh.hshval()));
-        return *this; };
+        return *this; }
     // Creating from raw data (sameHash functions)
     V3Hash() { setBoth(1, 0); }
     // cppcheck-suppress noExplicitConstructor
diff --git a/src/V3AstNodes.cpp b/src/V3AstNodes.cpp
index 1ac50e7bf..835758651 100644
--- a/src/V3AstNodes.cpp
+++ b/src/V3AstNodes.cpp
@@ -630,7 +630,7 @@ std::pair<uint32_t,uint32_t> AstNodeDType::dimensions(bool includeBasic) {
         else if (const AstBasicDType* adtypep = VN_CAST(dtypep, BasicDType)) {
             if (includeBasic && (adtypep->isRanged() || adtypep->isString())) packed++;
         }
-        else if (const AstStructDType* sdtypep = VN_CAST(dtypep, StructDType)) {
+        else if (VN_IS(dtypep, StructDType)) {
             packed++;
         }
         break;
diff --git a/src/V3AstNodes.h b/src/V3AstNodes.h
index 04bd1b04e..dcba2822f 100644
--- a/src/V3AstNodes.h
+++ b/src/V3AstNodes.h
@@ -996,7 +996,7 @@ public:
 class AstVoidDType : public AstNodeDType {
     // For e.g. a function returning void
 public:
-    AstVoidDType(FileLine* fl)
+    explicit AstVoidDType(FileLine* fl)
         : ASTGEN_SUPER(fl) { dtypep(this); }
     ASTNODE_NODE_FUNCS(VoidDType)
     virtual void dumpSmall(std::ostream& str) const;
@@ -1404,7 +1404,8 @@ public:
     }
     AstCMethodHard(FileLine* fl, AstNode* fromp, const string& name, AstNode* pinsp)
         : ASTGEN_SUPER(fl, false)
-        , m_name(name) {
+        , m_name(name)
+        , m_pure(false) {
         setOp1p(fromp);
         addNOp2p(pinsp);
     }
@@ -2419,7 +2420,7 @@ public:
 class AstUnbounded : public AstNode {
     // A $ in the parser, used for unbounded and queues
 public:
-    AstUnbounded(FileLine* fl)
+    explicit AstUnbounded(FileLine* fl)
         : ASTGEN_SUPER(fl) {}
     ASTNODE_NODE_FUNCS(Unbounded)
     virtual string emitVerilog() { return "$"; }
@@ -3615,7 +3616,7 @@ public:
 
 class AstReturn : public AstNodeStmt {
 public:
-    AstReturn(FileLine* fl, AstNode* lhsp = NULL)
+    explicit AstReturn(FileLine* fl, AstNode* lhsp = NULL)
         : ASTGEN_SUPER(fl) {
         setNOp1p(lhsp);
     }
@@ -3916,7 +3917,7 @@ class AstNew : public AstNodeMath {
     // Parents: math|stmt
     // Children: varref|arraysel, math
 public:
-    AstNew(FileLine* fl)
+    explicit AstNew(FileLine* fl)
         : ASTGEN_SUPER(fl) {
         dtypep(NULL);  // V3Width will resolve
     }
@@ -6471,9 +6472,10 @@ class AstTextBlock : public AstNodeSimpleText {
 private:
     bool m_commas;  // Comma separate emitted children
 public:
-    AstTextBlock(FileLine* fl, const string& textp="", bool tracking=false,
-                 bool commas=false)
-        : ASTGEN_SUPER(fl, textp, tracking), m_commas(commas) {}
+    explicit AstTextBlock(FileLine* fl, const string& textp = "", bool tracking = false,
+                          bool commas = false)
+        : ASTGEN_SUPER(fl, textp, tracking)
+        , m_commas(commas) {}
     ASTNODE_NODE_FUNCS(TextBlock)
     void commas(bool flag) { m_commas = flag; }
     bool commas() const { return m_commas; }
@@ -6840,7 +6842,7 @@ public:
         dtypeFrom(exprsp);
     }
     AstCMath(FileLine* fl, const string& textStmt, int setwidth, bool cleanOut=true)
-        : ASTGEN_SUPER(fl), m_cleanOut(cleanOut) {
+        : ASTGEN_SUPER(fl), m_cleanOut(cleanOut), m_pure(true) {
         addNOp1p(new AstText(fl, textStmt, true));
         if (setwidth) { dtypeSetLogicSized(setwidth, AstNumeric::UNSIGNED); }
     }
diff --git a/src/V3CUse.cpp b/src/V3CUse.cpp
index 72ed029ac..f13ed23d0 100644
--- a/src/V3CUse.cpp
+++ b/src/V3CUse.cpp
@@ -115,11 +115,11 @@ public:
 void V3CUse::cUseAll(AstNetlist* nodep) {
     UINFO(2, __FUNCTION__ << ": " << endl);
     // Call visitor separately for each module, so visitor state is cleared
-    for (AstNodeModule* nodep = v3Global.rootp()->modulesp(); nodep;
-         nodep = VN_CAST(nodep->nextp(), NodeModule)) {
+    for (AstNodeModule* modp = v3Global.rootp()->modulesp(); modp;
+         modp = VN_CAST(modp->nextp(), NodeModule)) {
         // Insert under this module; someday we should e.g. make Ast
         // for each output file and put under that
-        CUseVisitor visitor(nodep);
+        CUseVisitor visitor(modp);
     }
     V3Global::dumpCheckGlobalTree("cuse", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
 }
diff --git a/src/V3Config.cpp b/src/V3Config.cpp
index 0528ca921..b1f0b0237 100644
--- a/src/V3Config.cpp
+++ b/src/V3Config.cpp
@@ -41,9 +41,9 @@ template <typename T> class V3ConfigWildcardResolver {
 
     Map m_mapWildcard;  // Wildcard strings to entities
     Map m_mapResolved;  // Resolved strings to converged entities
-    typename Map::iterator m_last;  // Last access, will probably hit again
 public:
-    V3ConfigWildcardResolver() { m_last = m_mapResolved.end(); }
+    V3ConfigWildcardResolver() {}
+    ~V3ConfigWildcardResolver() {}
 
     /// Update into maps from other
     void update(const V3ConfigWildcardResolver& other) {
@@ -63,10 +63,6 @@ public:
     }
     // Access an entity and resolve wildcards that match it
     T* resolve(const string& name) {
-        // Lookup if recently accessed matches
-        if (VL_LIKELY(m_last != m_mapResolved.end()) && VL_LIKELY(m_last->first == name)) {
-            return &m_last->second;
-        }
         // Lookup if it was resolved before, typically not
         typename Map::iterator it = m_mapResolved.find(name);
         if (VL_UNLIKELY(it != m_mapResolved.end())) { return &it->second; }
diff --git a/src/V3Const.cpp b/src/V3Const.cpp
index 2ae16580a..5ba0db8a2 100644
--- a/src/V3Const.cpp
+++ b/src/V3Const.cpp
@@ -2087,7 +2087,7 @@ private:
                     default:  // Most operators, just move to next argument
                         if (argp) {
                             AstNode* nextp = argp->nextp();
-                            if (argp && VN_IS(argp, Const)) {  // Convert it
+                            if (VN_IS(argp, Const)) {  // Convert it
                                 string out = VN_CAST(argp, Const)->num().displayed(nodep, fmt);
                                 UINFO(9,"     DispConst: "<<fmt<<" -> "<<out
                                       <<"  for "<<argp<<endl);
diff --git a/src/V3EmitC.cpp b/src/V3EmitC.cpp
index 0d9316a81..cd424a131 100644
--- a/src/V3EmitC.cpp
+++ b/src/V3EmitC.cpp
@@ -382,9 +382,15 @@ public:
         puts(");\n");
     }
     virtual void visit(AstCoverInc* nodep) VL_OVERRIDE {
-        puts("++(vlSymsp->__Vcoverage[");
-        puts(cvtToStr(nodep->declp()->dataDeclThisp()->binNum()));
-        puts("]);\n");
+        if (v3Global.opt.threads()) {
+            puts("vlSymsp->__Vcoverage[");
+            puts(cvtToStr(nodep->declp()->dataDeclThisp()->binNum()));
+            puts("].fetch_add(1, std::memory_order_relaxed);\n");
+        } else {
+            puts("++(vlSymsp->__Vcoverage[");
+            puts(cvtToStr(nodep->declp()->dataDeclThisp()->binNum()));
+            puts("]);\n");
+        }
     }
     virtual void visit(AstCReturn* nodep) VL_OVERRIDE {
         puts("return (");
@@ -1074,6 +1080,7 @@ class EmitCImp : EmitCStmts {
     // METHODS
 
     void doubleOrDetect(AstChangeDet* changep, bool& gotOne) {
+        // cppcheck-suppress variableScope
         static int s_addDoubleOr = 10;  // Determined experimentally as best
         if (!changep->rhsp()) {
             if (!gotOne) gotOne = true;
@@ -1447,7 +1454,8 @@ class EmitCImp : EmitCStmts {
             puts(emitVarResetRecurse(varp, dtypep, 0, ""));
         }
     }
-    string emitVarResetRecurse(AstVar* varp, AstNodeDType* dtypep, int depth, string suffix) {
+    string emitVarResetRecurse(AstVar* varp, AstNodeDType* dtypep, int depth,
+                               const string& suffix) {
         dtypep = dtypep->skipRefp();
         AstBasicDType* basicp = dtypep->basicp();
         // Returns string to do resetting, empty to do nothing (which caller should handle)
@@ -1953,7 +1961,9 @@ void EmitCImp::emitCoverageDecl(AstNodeModule* modp) {
     if (v3Global.opt.coverage()) {
         ofp()->putsPrivate(true);
         putsDecoration("// Coverage\n");
-        puts("void __vlCoverInsert(uint32_t* countp, bool enable, const char* filenamep, int lineno, int column,\n");
+        puts("void __vlCoverInsert(");
+        puts(v3Global.opt.threads() ? "std::atomic<uint32_t>" : "uint32_t");
+        puts("* countp, bool enable, const char* filenamep, int lineno, int column,\n");
         puts(   "const char* hierp, const char* pagep, const char* commentp);\n");
     }
 }
@@ -2068,14 +2078,22 @@ void EmitCImp::emitCoverageImp(AstNodeModule* modp) {
         puts("\n// Coverage\n");
         // Rather than putting out VL_COVER_INSERT calls directly, we do it via this function
         // This gets around gcc slowness constructing all of the template arguments.
-        puts("void " + prefixNameProtect(m_modp)
-             + "::__vlCoverInsert(uint32_t* countp, bool enable,"
-             + " const char* filenamep, int lineno, int column,\n");
+        puts("void " + prefixNameProtect(m_modp) + "::__vlCoverInsert(");
+        puts(v3Global.opt.threads() ? "std::atomic<uint32_t>" : "uint32_t");
+        puts("* countp, bool enable, const char* filenamep, int lineno, int column,\n");
         puts(   "const char* hierp, const char* pagep, const char* commentp) {\n");
-        puts(   "static uint32_t fake_zero_count = 0;\n");  // static doesn't need save-restore as constant
-        puts(   "if (!enable) countp = &fake_zero_count;\n");  // Used for second++ instantiation of identical bin
-        puts(   "*countp = 0;\n");
-        puts(   "VL_COVER_INSERT(countp,");
+        if (v3Global.opt.threads()) {
+            puts(   "assert(sizeof(uint32_t) == sizeof(std::atomic<uint32_t>));\n");
+            puts(   "uint32_t* count32p = reinterpret_cast<uint32_t*>(countp);\n");
+        } else {
+            puts(   "uint32_t* count32p = countp;\n");
+        }
+        // static doesn't need save-restore as is constant
+        puts(   "static uint32_t fake_zero_count = 0;\n");
+        // Used for second++ instantiation of identical bin
+        puts(   "if (!enable) count32p = &fake_zero_count;\n");
+        puts(   "*count32p = 0;\n");
+        puts("VL_COVER_INSERT(count32p,");
         puts(   "  \"filename\",filenamep,");
         puts(   "  \"lineno\",lineno,");
         puts(   "  \"column\",column,\n");
@@ -2644,8 +2662,10 @@ void EmitCImp::emitInt(AstNodeModule* modp) {
                 if (!did) {
                     did = true;
                     putsDecoration("// CELLS\n");
-                    if (modp->isTop()) puts("// Public to allow access to /*verilator_public*/ items;\n");
-                    if (modp->isTop()) puts("// otherwise the application code can consider these internals.\n");
+                    if (modp->isTop()) {
+                        puts("// Public to allow access to /*verilator_public*/ items;\n");
+                        puts("// otherwise the application code can consider these internals.\n");
+                    }
                 }
                 puts(prefixNameProtect(cellp->modp()) + "* " + cellp->nameProtect() + ";\n");
             }
diff --git a/src/V3EmitCSyms.cpp b/src/V3EmitCSyms.cpp
index 214fff4fd..6cdc1c635 100644
--- a/src/V3EmitCSyms.cpp
+++ b/src/V3EmitCSyms.cpp
@@ -437,7 +437,10 @@ void EmitCSyms::emitSymHdr() {
 
     if (m_coverBins) {
         puts("\n// COVERAGE\n");
-        puts("uint32_t __Vcoverage["); puts(cvtToStr(m_coverBins)); puts("];\n");
+        puts(v3Global.opt.threads() ? "std::atomic<uint32_t>" : "uint32_t");
+        puts(" __Vcoverage[");
+        puts(cvtToStr(m_coverBins));
+        puts("];\n");
     }
 
     if (!m_scopeNames.empty()) {  // Scope names
diff --git a/src/V3EmitMk.cpp b/src/V3EmitMk.cpp
index ad7d91386..284e02bc4 100644
--- a/src/V3EmitMk.cpp
+++ b/src/V3EmitMk.cpp
@@ -189,7 +189,7 @@ public:
             string cppfile = *it;
             of.puts("\t"+V3Os::filenameNonExt(cppfile)+" \\\n");
             string dir = V3Os::filenameDir(cppfile);
-            if (dirs.find(dir) == dirs.end()) dirs.insert(dir);
+            dirs.insert(dir);
         }
         of.puts("\n");
 
diff --git a/src/V3FileLine.cpp b/src/V3FileLine.cpp
index d27440602..7dad8ea66 100644
--- a/src/V3FileLine.cpp
+++ b/src/V3FileLine.cpp
@@ -120,6 +120,7 @@ void VFileContent::pushText(const string& text) {
 
 string VFileContent::getLine(int lineno) const {
     // Return error text rather than asserting so the user isn't left without a message
+    // cppcheck-suppress negativeContainerIndex
     if (VL_UNCOVERABLE(lineno < 0 || lineno >= (int)m_lines.size())) {
         if (debug() || v3Global.opt.debugCheck()) {
             return ("%Error-internal-contents-bad-ct"+cvtToStr(m_id)
diff --git a/src/V3FileLine.h b/src/V3FileLine.h
index 44ccb7ab9..dc9643d26 100644
--- a/src/V3FileLine.h
+++ b/src/V3FileLine.h
@@ -119,7 +119,7 @@ private:
         return *defFilelinep;
     }
 public:
-    FileLine(const string& filename) {
+    explicit FileLine(const string& filename) {
         m_lastLineno = m_firstLineno = 0;
         m_lastColumn = m_firstColumn = 0;
         m_filenameno = singleton().nameToNumber(filename);
diff --git a/src/V3Gate.cpp b/src/V3Gate.cpp
index f4db76775..7ecacc26a 100644
--- a/src/V3Gate.cpp
+++ b/src/V3Gate.cpp
@@ -453,9 +453,11 @@ private:
             UASSERT_OBJ(varscp, nodep, "Var didn't get varscoped in V3Scope.cpp");
             GateVarVertex* vvertexp = makeVarVertex(varscp);
             UINFO(5," VARREF to "<<varscp<<endl);
-            if (m_inSenItem) vvertexp->setIsClock();
-            // For SYNCASYNCNET
-            if (m_inSenItem) varscp->user2(true);
+            if (m_inSenItem) {
+                vvertexp->setIsClock();
+                // For SYNCASYNCNET
+                varscp->user2(true);
+            }
             else if (m_activep && m_activep->hasClocked() && !nodep->lvalue()) {
                 if (varscp->user2()) {
                     if (!vvertexp->rstAsyncNodep()) vvertexp->rstAsyncNodep(nodep);
@@ -712,7 +714,7 @@ bool GateVisitor::elimLogicOkOutputs(GateLogicVertex* consumeVertexp,
     for (GateVarRefList::const_iterator it = rhsVarRefs.begin();
          it != rhsVarRefs.end(); ++it) {
         AstVarScope* vscp = (*it)->varScopep();
-        if (varscopes.find(vscp) == varscopes.end()) varscopes.insert(vscp);
+        varscopes.insert(vscp);
     }
     for (V3GraphEdge* edgep = consumeVertexp->outBeginp(); edgep; edgep = edgep->outNextp()) {
         GateVarVertex* consVVertexp = dynamic_cast<GateVarVertex*>(edgep->top());
diff --git a/src/V3Graph.h b/src/V3Graph.h
index c57aa3923..14c757494 100644
--- a/src/V3Graph.h
+++ b/src/V3Graph.h
@@ -65,7 +65,7 @@ public:
     const char* ascii() const {
         static const char* const names[] = { "FORWARD", "REVERSE" };
         return names[m_e];
-    };
+    }
     // METHODS unique to this class
     GraphWay invert() const { return m_e == FORWARD ? REVERSE : FORWARD; }
     bool forward() const { return m_e == FORWARD; }
diff --git a/src/V3GraphDfa.cpp b/src/V3GraphDfa.cpp
index 1716f8657..81af99039 100644
--- a/src/V3GraphDfa.cpp
+++ b/src/V3GraphDfa.cpp
@@ -599,6 +599,7 @@ public:
         if (debug()>=6) m_graphp->dumpDotFilePrefixed("comp_out");
     }
     ~DfaGraphComplement() {}
+    VL_UNCOPYABLE(DfaGraphComplement);
 };
 
 void DfaGraph::dfaComplement() {
diff --git a/src/V3GraphDfa.h b/src/V3GraphDfa.h
index 21009ef57..193279631 100644
--- a/src/V3GraphDfa.h
+++ b/src/V3GraphDfa.h
@@ -89,7 +89,7 @@ class DfaVertex : public V3GraphVertex {
     bool m_accepting;  // Accepting state?
 public:
     // CONSTRUCTORS
-    DfaVertex(DfaGraph* graphp, bool start=false, bool accepting=false)
+    explicit DfaVertex(DfaGraph* graphp, bool start=false, bool accepting=false)
         : V3GraphVertex(graphp)
         , m_start(start), m_accepting(accepting) {}
     using V3GraphVertex::clone;  // We are overriding, not overloading clone(V3Graph*)
diff --git a/src/V3GraphPathChecker.h b/src/V3GraphPathChecker.h
index 2d248363b..7b6024eee 100644
--- a/src/V3GraphPathChecker.h
+++ b/src/V3GraphPathChecker.h
@@ -42,8 +42,8 @@ class GraphPathChecker : GraphAlg<const V3Graph> {
 
  public:
     // CONSTRUCTORS
-    GraphPathChecker(const V3Graph* graphp,
-                     V3EdgeFuncP edgeFuncp = V3GraphEdge::followAlwaysTrue);
+    explicit GraphPathChecker(const V3Graph* graphp,
+                              V3EdgeFuncP edgeFuncp = V3GraphEdge::followAlwaysTrue);
     ~GraphPathChecker();
 
     // METHODS
diff --git a/src/V3GraphStream.h b/src/V3GraphStream.h
index a1bd9a1bb..b949b0418 100644
--- a/src/V3GraphStream.h
+++ b/src/V3GraphStream.h
@@ -95,9 +95,9 @@ private:
 
 public:
     // CONSTRUCTORS
-    GraphStream(const V3Graph* graphp,
-                GraphWay way = GraphWay::FORWARD,
-                const T_Compare& lessThan = T_Compare())
+    explicit GraphStream(const V3Graph* graphp,
+                         GraphWay way = GraphWay::FORWARD,
+                         const T_Compare& lessThan = T_Compare())
         // NOTE: Perhaps REVERSE way should also reverse the sense of the
         // lessThan function? For now the only usage of REVERSE is not
         // sensitive to its lessThan at all, so it doesn't matter.
diff --git a/src/V3Inline.cpp b/src/V3Inline.cpp
index 68843c59c..dd32eda44 100644
--- a/src/V3Inline.cpp
+++ b/src/V3Inline.cpp
@@ -178,10 +178,10 @@ private:
             // update user4 (statement count) to reflect that:
             int statements = modp->user4();
             LocalInstanceMap& localsr = m_instances[modp];
-            for (LocalInstanceMap::iterator it = localsr.begin(); it != localsr.end(); ++it) {
-                AstNodeModule* childp = it->first;
+            for (LocalInstanceMap::iterator iti = localsr.begin(); iti != localsr.end(); ++iti) {
+                AstNodeModule* childp = iti->first;
                 if (childp->user1()) {  // inlining child
-                    statements += (childp->user4() * it->second);
+                    statements += (childp->user4() * iti->second);
                 }
             }
             modp->user4(statements);
diff --git a/src/V3LangCode.h b/src/V3LangCode.h
index ab4509e97..c66d4b76d 100644
--- a/src/V3LangCode.h
+++ b/src/V3LangCode.h
@@ -59,7 +59,7 @@ public:
             "1800-2017"
         };
         return names[m_e];
-    };
+    }
     static V3LangCode mostRecent() { return V3LangCode(L1800_2017); }
     bool systemVerilog() const { return m_e == L1800_2005 || m_e == L1800_2009
             || m_e == L1800_2012 || m_e == L1800_2017; }
diff --git a/src/V3LinkCells.cpp b/src/V3LinkCells.cpp
index 1a49d5855..8e4ea4b29 100644
--- a/src/V3LinkCells.cpp
+++ b/src/V3LinkCells.cpp
@@ -385,9 +385,7 @@ private:
                                      <<pinp->prettyNameQ());
                     }
                 }
-                if (ports.find(pinp->name()) == ports.end()) {
-                    ports.insert(pinp->name());
-                }
+                ports.insert(pinp->name());
             }
             // We search ports, rather than in/out declarations as they aren't resolved yet,
             // and it's easier to do it now than in V3LinkDot when we'd need to repeat steps.
diff --git a/src/V3LinkDot.cpp b/src/V3LinkDot.cpp
index 30d88d6a8..c7a045d1d 100644
--- a/src/V3LinkDot.cpp
+++ b/src/V3LinkDot.cpp
@@ -2070,11 +2070,21 @@ private:
                         refp->varp(varp);
                         m_ds.m_dotText = "";
                         if (m_ds.m_unresolved && m_ds.m_unlinkedScope) {
-                            newp = new AstUnlinkedRef(nodep->fileline(), VN_CAST(refp, VarXRef),
-                                                      refp->name(),
-                                                      m_ds.m_unlinkedScope->unlinkFrBack());
-                            m_ds.m_unlinkedScope = NULL;
-                            m_ds.m_unresolved = false;
+                            string dotted = refp->dotted();
+                            size_t pos = dotted.find("__BRA__??__KET__");
+                            // Arrays of interfaces all have the same parameters
+                            if (pos != string::npos && varp->isParam()
+                                && VN_IS(m_ds.m_unlinkedScope, CellArrayRef)) {
+                                refp->dotted(dotted.substr(0, pos));
+                                newp = refp;
+                            } else {
+                                newp = new AstUnlinkedRef(nodep->fileline(),
+                                                          VN_CAST(refp, VarXRef),
+                                                          refp->name(),
+                                                          m_ds.m_unlinkedScope->unlinkFrBack());
+                                m_ds.m_unlinkedScope = NULL;
+                                m_ds.m_unresolved = false;
+                           }
                         } else {
                             newp = refp;
                         }
@@ -2241,7 +2251,6 @@ private:
                     }
                 }
             } else {
-                string baddot;
                 VSymEnt* foundp = m_statep->findSymPrefixed(dotSymp, nodep->name(), baddot);
                 AstVarScope* vscp = foundp ? VN_CAST(foundp->nodep(), VarScope) : NULL;
                 if (!vscp) {
diff --git a/src/V3Number.cpp b/src/V3Number.cpp
index 00a043c68..b5900bc51 100644
--- a/src/V3Number.cpp
+++ b/src/V3Number.cpp
@@ -1540,8 +1540,8 @@ V3Number& V3Number::opShiftRS(const V3Number& lhs, const V3Number& rhs, uint32_t
     if (rhs.isFourState()) return setAllBitsX();
     setZero();
     for (int bit=32; bit<rhs.width(); bit++) {
-        for (int bit=0; bit<this->width(); bit++) {
-            setBit(bit, lhs.bitIs(lbits-1));  // 0/1/X/Z
+        for (int sbit = 0; sbit < this->width(); sbit++) {
+            setBit(sbit, lhs.bitIs(lbits - 1));  // 0/1/X/Z
         }
         if (rhs.bitIs1(lbits-1)) setAllBits1();  // -1 else 0
         return *this;  // shift of over 2^32 must be -1/0
diff --git a/src/V3Number.h b/src/V3Number.h
index 73a2f4907..a53e886ca 100644
--- a/src/V3Number.h
+++ b/src/V3Number.h
@@ -151,7 +151,7 @@ public:
     V3Number(VerilogStringLiteral, AstNode* nodep, const string& str);
     class String {};
     V3Number(String, AstNode* nodep, const string& value) { init(nodep, 0); setString(value); }
-    V3Number(const V3Number* nump, int width = 1) {
+    explicit V3Number(const V3Number* nump, int width = 1) {
         init(NULL, width);
         m_fileline = nump->fileline();
     }
diff --git a/src/V3Options.cpp b/src/V3Options.cpp
index 7b3cc7735..eb56d87b2 100644
--- a/src/V3Options.cpp
+++ b/src/V3Options.cpp
@@ -182,9 +182,7 @@ void V3Options::checkParameters() {
 }
 
 void V3Options::addCppFile(const string& filename) {
-    if (m_cppFiles.find(filename) == m_cppFiles.end()) {
-        m_cppFiles.insert(filename);
-    }
+    m_cppFiles.insert(filename);
 }
 void V3Options::addCFlags(const string& filename) {
     m_cFlags.push_back(filename);
@@ -193,9 +191,7 @@ void V3Options::addLdLibs(const string& filename) {
     m_ldLibs.push_back(filename);
 }
 void V3Options::addFuture(const string& flag) {
-    if (m_futures.find(flag) == m_futures.end()) {
-        m_futures.insert(flag);
-    }
+    m_futures.insert(flag);
 }
 bool V3Options::isFuture(const string& flag) const {
     return m_futures.find(flag) != m_futures.end();
@@ -204,25 +200,19 @@ bool V3Options::isLibraryFile(const string& filename) const {
     return m_libraryFiles.find(filename) != m_libraryFiles.end();
 }
 void V3Options::addLibraryFile(const string& filename) {
-    if (m_libraryFiles.find(filename) == m_libraryFiles.end()) {
-        m_libraryFiles.insert(filename);
-    }
+    m_libraryFiles.insert(filename);
 }
 bool V3Options::isClocker(const string& signame) const {
     return m_clockers.find(signame) != m_clockers.end();
 }
 void V3Options::addClocker(const string& signame) {
-    if (m_clockers.find(signame) == m_clockers.end()) {
-        m_clockers.insert(signame);
-    }
+    m_clockers.insert(signame);
 }
 bool V3Options::isNoClocker(const string& signame) const {
     return m_noClockers.find(signame) != m_noClockers.end();
 }
 void V3Options::addNoClocker(const string& signame) {
-    if (m_noClockers.find(signame) == m_noClockers.end()) {
-        m_noClockers.insert(signame);
-    }
+    m_noClockers.insert(signame);
 }
 void V3Options::addVFile(const string& filename) {
     // We use a list for v files, because it's legal to have includes
diff --git a/src/V3Order.cpp b/src/V3Order.cpp
index 3cd4d6782..f594320b9 100644
--- a/src/V3Order.cpp
+++ b/src/V3Order.cpp
@@ -127,7 +127,7 @@ void OrderGraph::loopsVertexCb(V3GraphVertex* vertexp) {
                  <<"     Example path: "
                  <<vvertexp->varScp()->prettyName()<<endl;
     }
-};
+}
 
 //######################################################################
 
diff --git a/src/V3Param.cpp b/src/V3Param.cpp
index 7aee4f784..1d758de07 100644
--- a/src/V3Param.cpp
+++ b/src/V3Param.cpp
@@ -228,9 +228,9 @@ private:
         // Hitting a cell adds to the appropriate level of this level-sorted list,
         // so since cells originally exist top->bottom we process in top->bottom order too.
         while (!m_todoModps.empty()) {
-            LevelModMap::iterator it = m_todoModps.begin();
-            AstNodeModule* nodep = it->second;
-            m_todoModps.erase(it);
+            LevelModMap::iterator itm = m_todoModps.begin();
+            AstNodeModule* nodep = itm->second;
+            m_todoModps.erase(itm);
             if (!nodep->user5SetOnce()) {  // Process once; note clone() must clear so we do it again
                 m_modp = nodep;
                 UINFO(4," MOD   "<<nodep<<endl);
@@ -355,9 +355,16 @@ private:
                 if (VN_IS(backp, Var)
                     && VN_CAST(backp, Var)->isIfaceRef()
                     && VN_CAST(backp, Var)->childDTypep()
-                    && VN_CAST(VN_CAST(backp, Var)->childDTypep(), IfaceRefDType)) {
+                    && (VN_CAST(VN_CAST(backp, Var)->childDTypep(), IfaceRefDType)
+                        || (VN_CAST(VN_CAST(backp, Var)->childDTypep(), UnpackArrayDType)
+                            && VN_CAST(VN_CAST(backp, Var)->childDTypep()->getChildDTypep(),
+                                       IfaceRefDType)))) {
                     AstIfaceRefDType* ifacerefp
                         = VN_CAST(VN_CAST(backp, Var)->childDTypep(), IfaceRefDType);
+                    if (!ifacerefp) {
+                        ifacerefp = VN_CAST(VN_CAST(backp, Var)->childDTypep()->getChildDTypep(),
+                                            IfaceRefDType);
+                    }
                     // Interfaces passed in on the port map have ifaces
                     if (AstIface* ifacep = ifacerefp->ifacep()) {
                         if (dotted == backp->name()) {
diff --git a/src/V3Partition.cpp b/src/V3Partition.cpp
index e6fbc3cfd..f742fdad2 100644
--- a/src/V3Partition.cpp
+++ b/src/V3Partition.cpp
@@ -573,7 +573,7 @@ public:
         edges.erase(relativep);
     }
     bool hasRelative(GraphWay way, LogicMTask* relativep) {
-        EdgeSet& edges = m_edges[way];
+        const EdgeSet& edges = m_edges[way];
         return edges.has(relativep);
     }
     void checkRelativesCp(GraphWay way) const {
@@ -1584,7 +1584,7 @@ private:
             }
             UASSERT_OBJ(found, ap, "Sibling not found");
         }
-    };
+    }
 
     static const GraphWay* s_shortestWaywardCpInclusiveWay;
     static int shortestWaywardCpInclusive(const void* vap, const void* vbp) {
diff --git a/src/V3PreProc.cpp b/src/V3PreProc.cpp
index f49464eae..102ca4cef 100644
--- a/src/V3PreProc.cpp
+++ b/src/V3PreProc.cpp
@@ -135,7 +135,7 @@ public:
                "ps_DEFFORM", "ps_DEFVALUE", "ps_DEFPAREN", "ps_DEFARG",
                "ps_INCNAME", "ps_ERRORNAME", "ps_JOIN", "ps_STRIFY"};
         return states[s];
-    };
+    }
 
     std::stack<ProcState> m_states;  ///< Current state of parser
     int         m_off;          ///< If non-zero, ifdef level is turned off, don't dump text
diff --git a/src/V3PreProc.h b/src/V3PreProc.h
index b7cb47103..9e09dfe93 100644
--- a/src/V3PreProc.h
+++ b/src/V3PreProc.h
@@ -102,8 +102,8 @@ public:
 protected:
     // CONSTRUCTORS
     V3PreProc() {
-        m_debug=0;
-    };
+        m_debug = 0;
+    }
     void configure(FileLine* fl);
 public:
     static V3PreProc* createPreProc(FileLine* fl);
diff --git a/src/V3Scoreboard.h b/src/V3Scoreboard.h
index db6362929..8fd72dcd5 100644
--- a/src/V3Scoreboard.h
+++ b/src/V3Scoreboard.h
@@ -505,6 +505,6 @@ private:
 
 namespace V3ScoreboardBase {
     void selfTest();
-};
+}
 
 #endif  // Guard
diff --git a/src/V3Simulate.h b/src/V3Simulate.h
index f97876d6b..86b934e7a 100644
--- a/src/V3Simulate.h
+++ b/src/V3Simulate.h
@@ -993,8 +993,8 @@ private:
                             clearOptimizable(nodep, "Argument for $display like statement is not constant");
                             break;
                         }
-                        string format = string("%") + pos[0];
-                        result += constp->num().displayed(nodep, format);
+                        string pformat = string("%") + pos[0];
+                        result += constp->num().displayed(nodep, pformat);
                     } else {
                         switch (tolower(pos[0])) {
                         case '%': result += "%"; break;
diff --git a/src/V3Stats.cpp b/src/V3Stats.cpp
index 064ed353f..27562f72f 100644
--- a/src/V3Stats.cpp
+++ b/src/V3Stats.cpp
@@ -204,7 +204,7 @@ private:
         if (m_fast && nodep->evalp()) {
             m_instrs = 0;
             m_counting = true;
-            if (nodep->evalp()) iterateChildrenConst(nodep->evalp());
+            iterateChildrenConst(nodep->evalp());
             m_counting = false;
         }
         allNodes(nodep);
diff --git a/src/V3SymTable.h b/src/V3SymTable.h
index da7185397..b0a504caa 100644
--- a/src/V3SymTable.h
+++ b/src/V3SymTable.h
@@ -163,9 +163,9 @@ public:
         // Suggest alternative symbol candidates without looking upward through symbol hierarchy
         for (IdNameMap::const_iterator it = m_idNameMap.begin();
              it != m_idNameMap.end(); ++it) {
-            const AstNode* nodep = it->second->nodep();
-            if (nodep && (!matcherp || matcherp->nodeMatch(nodep))) {
-                spellerp->pushCandidate(nodep->prettyName());
+            const AstNode* itemp = it->second->nodep();
+            if (itemp && (!matcherp || matcherp->nodeMatch(itemp))) {
+                spellerp->pushCandidate(itemp->prettyName());
             }
         }
     }
@@ -249,9 +249,9 @@ public:
         if (prettyName=="") prettyName = lookp->prettyName();
         string scopes;
         for (IdNameMap::iterator it = m_idNameMap.begin(); it!=m_idNameMap.end(); ++it) {
-            AstNode* nodep = it->second->nodep();
-            if (VN_IS(nodep, Cell)
-                || (VN_IS(nodep, Module) && VN_CAST(nodep, Module)->isTop())) {
+            AstNode* itemp = it->second->nodep();
+            if (VN_IS(itemp, Cell)
+                || (VN_IS(itemp, Module) && VN_CAST(itemp, Module)->isTop())) {
                 if (scopes != "") scopes += ", ";
                 scopes += AstNode::prettyName(it->first);
             }
diff --git a/src/V3Task.cpp b/src/V3Task.cpp
index 72cb3c9e4..ac9d669c2 100644
--- a/src/V3Task.cpp
+++ b/src/V3Task.cpp
@@ -415,12 +415,12 @@ private:
 
                     // Even if it's referencing a varref, we still make a temporary
                     // Else task(x,x,x) might produce incorrect results
-                    AstVarScope* outvscp
+                    AstVarScope* tempvscp
                         = createVarScope(portp, namePrefix+"__"+portp->shortName());
-                    portp->user2p(outvscp);
-                    AstAssign* assp = new AstAssign(pinp->fileline(),
-                                                    pinp,
-                                                    new AstVarRef(outvscp->fileline(), outvscp, false));
+                    portp->user2p(tempvscp);
+                    AstAssign* assp
+                        = new AstAssign(pinp->fileline(), pinp,
+                                        new AstVarRef(tempvscp->fileline(), tempvscp, false));
                     assp->fileline()->modifyWarnOff(V3ErrorCode::BLKSEQ, true);  // Ok if in <= block
                     // Put assignment BEHIND of all other statements
                     beginp->addNext(assp);
@@ -469,7 +469,7 @@ private:
         // Iteration requires a back, so put under temporary node
         {
             AstBegin* tempp = new AstBegin(beginp->fileline(), "[EditWrapper]", beginp);
-            TaskRelinkVisitor visit (tempp);
+            TaskRelinkVisitor visitor(tempp);
             tempp->stmtsp()->unlinkFrBackWithNext();
             VL_DO_DANGLING(tempp->deleteTree(), tempp);
         }
@@ -1073,7 +1073,7 @@ private:
         // Iteration requires a back, so put under temporary node
         {
             AstBegin* tempp = new AstBegin(cfuncp->fileline(), "[EditWrapper]", cfuncp);
-            TaskRelinkVisitor visit (tempp);
+            TaskRelinkVisitor visitor(tempp);
             tempp->stmtsp()->unlinkFrBackWithNext();
             VL_DO_DANGLING(tempp->deleteTree(), tempp);
         }
diff --git a/src/V3Trace.cpp b/src/V3Trace.cpp
index 864010e45..aa6f67756 100644
--- a/src/V3Trace.cpp
+++ b/src/V3Trace.cpp
@@ -449,9 +449,7 @@ private:
                         break;
                     } else {
                         uint32_t acode = cfvertexp->activityCode();
-                        if (actset.find(acode) == actset.end()) {
-                            actset.insert(acode);
-                        }
+                        actset.insert(acode);
                     }
                 }
                 // If a trace doesn't have activity, it's constant, and we
diff --git a/src/V3Unroll.cpp b/src/V3Unroll.cpp
index 25408ef5b..73e8c5dd6 100644
--- a/src/V3Unroll.cpp
+++ b/src/V3Unroll.cpp
@@ -388,6 +388,7 @@ private:
             // Grab assignment
             AstNode* incp = NULL;  // Should be last statement
             if (nodep->incsp()) V3Const::constifyEdit(nodep->incsp());
+            // cppcheck-suppress duplicateCondition
             if (nodep->incsp()) incp = nodep->incsp();
             else {
                 for (incp = nodep->bodysp(); incp && incp->nextp(); incp = incp->nextp()) {}
diff --git a/src/V3Width.cpp b/src/V3Width.cpp
index 8c18da24c..512bb9676 100644
--- a/src/V3Width.cpp
+++ b/src/V3Width.cpp
@@ -1138,9 +1138,9 @@ private:
                 default: nodep->v3error("Unhandled attribute type");
                 }
             } else {
-                std::pair<uint32_t, uint32_t> dim
+                std::pair<uint32_t, uint32_t> dimp
                     = nodep->fromp()->dtypep()->skipRefp()->dimensions(true);
-                uint32_t msbdim = dim.first + dim.second;
+                uint32_t msbdim = dimp.first + dimp.second;
                 if (!nodep->dimp() || msbdim < 1) {
                     int dim = 1;
                     AstConst* newp = dimensionValue(nodep->fileline(), nodep->fromp()->dtypep(),
@@ -2291,7 +2291,6 @@ private:
         userIterateChildren(nodep, WidthVP(SELF, BOTH).p());
         AstClassRefDType* refp = VN_CAST(m_vup->dtypeNullp(), ClassRefDType);
         if (!refp) {  // e.g. int a = new;
-            if (refp) UINFO(1, "Got refp "<<refp<<endl);
             nodep->v3error("new() not expected in this context");
             return;
         }
@@ -2454,9 +2453,9 @@ private:
                 if (VN_IS(valuep, Const)) {
                     // Forming a AstConcat will cause problems with
                     // unsized (uncommitted sized) constants
-                    if (AstNode* newp = WidthCommitVisitor::newIfConstCommitSize(VN_CAST(valuep, Const))) {
+                    if (AstNode* newccp = WidthCommitVisitor::newIfConstCommitSize(VN_CAST(valuep, Const))) {
                         VL_DO_DANGLING(pushDeletep(valuep), valuep);
-                        valuep = newp;
+                        valuep = newccp;
                     }
                 }
                 if (!newp) newp = valuep;
@@ -2574,9 +2573,10 @@ private:
                 if (VN_IS(valuep, Const)) {
                     // Forming a AstConcat will cause problems with
                     // unsized (uncommitted sized) constants
-                    if (AstNode* newp = WidthCommitVisitor::newIfConstCommitSize(VN_CAST(valuep, Const))) {
+                    if (AstNode* newccp
+                        = WidthCommitVisitor::newIfConstCommitSize(VN_CAST(valuep, Const))) {
                         VL_DO_DANGLING(pushDeletep(valuep), valuep);
-                        valuep = newp;
+                        valuep = newccp;
                     }
                 }
                 {  // Packed. Convert to concat for now.
@@ -3675,9 +3675,9 @@ private:
                 if (shiftp && shiftp->num().mostSetBitP1() <= 32) {
                     // If (number)<<96'h1, then make it into (number)<<32'h1
                     V3Number num (shiftp, 32, 0); num.opAssign(shiftp->num());
-                    AstNode* shiftp = nodep->rhsp();
-                    nodep->rhsp()->replaceWith(new AstConst(shiftp->fileline(), num));
-                    VL_DO_DANGLING(shiftp->deleteTree(), shiftp);
+                    AstNode* shiftrhsp = nodep->rhsp();
+                    nodep->rhsp()->replaceWith(new AstConst(shiftrhsp->fileline(), num));
+                    VL_DO_DANGLING(shiftrhsp->deleteTree(), shiftrhsp);
                 }
             }
         }
diff --git a/src/V3WidthSel.cpp b/src/V3WidthSel.cpp
index d6e866185..ae3e4946d 100644
--- a/src/V3WidthSel.cpp
+++ b/src/V3WidthSel.cpp
@@ -91,9 +91,9 @@ private:
         if (const AstNodeArrayDType* adtypep = VN_CAST(ddtypep, NodeArrayDType)) {
             fromRange = adtypep->declRange();
         }
-        else if (const AstAssocArrayDType* adtypep = VN_CAST(ddtypep, AssocArrayDType)) {
+        else if (VN_IS(ddtypep, AssocArrayDType)) {
         }
-        else if (const AstQueueDType* adtypep = VN_CAST(ddtypep, QueueDType)) {
+        else if (VN_IS(ddtypep, QueueDType)) {
         }
         else if (const AstNodeUOrStructDType* adtypep = VN_CAST(ddtypep, NodeUOrStructDType)) {
             fromRange = adtypep->declRange();
diff --git a/src/VlcMain.cpp b/src/VlcMain.cpp
index aa1247fa2..99e018446 100644
--- a/src/VlcMain.cpp
+++ b/src/VlcMain.cpp
@@ -42,9 +42,7 @@
 // VlcOptions
 
 void VlcOptions::addReadFile(const string& filename) {
-    if (m_readFiles.find(filename) == m_readFiles.end()) {
-        m_readFiles.insert(filename);
-    }
+    m_readFiles.insert(filename);
 }
 
 string VlcOptions::version() {
diff --git a/src/astgen b/src/astgen
index ed42a54bf..ad1d5ed45 100644
--- a/src/astgen
+++ b/src/astgen
@@ -352,7 +352,7 @@ sub write_types {
     printf $fh "            \"_ENUM_END\"\n";
     printf $fh "        };\n";
     printf $fh "        return names[m_e];\n";
-    printf $fh "    };\n";
+    printf $fh "    }\n";
     $fh->close();
 }
 
diff --git a/src/cppcheck_filtered b/src/cppcheck_filtered
index 6bc699092..1f962ea58 100755
--- a/src/cppcheck_filtered
+++ b/src/cppcheck_filtered
@@ -137,6 +137,9 @@ sub _suppress {
 
     return undef if $filename eq "*";
 
+    # Cleanup for e.g. ../V3AstNodes.h
+    $filename = "src/$1" if $filename =~ m!^\.\./(.*)!;
+
     # Specific suppressions
     return 1 if $id eq "missingInclude" && $filename =~ m!systemc.h!;
     return 1 if $id eq "missingInclude" && $filename =~ m!svdpi.h!;
diff --git a/src/verilog.y b/src/verilog.y
index 875564aa3..acfcf0329 100644
--- a/src/verilog.y
+++ b/src/verilog.y
@@ -114,12 +114,14 @@ public:
 	if (!rangep) return exprp;
 	else return new AstGatePin(rangep->fileline(), exprp, rangep->cloneTree(true));
     }
-    void endLabel(FileLine* fl, AstNode* nodep, string* endnamep) { endLabel(fl, nodep->prettyName(), endnamep); }
-    void endLabel(FileLine* fl, string name, string* endnamep) {
-	if (fl && endnamep && *endnamep != "" && name != *endnamep
-	    && name != AstNode::prettyName(*endnamep)) {
-	    fl->v3warn(ENDLABEL,"End label '"<<*endnamep<<"' does not match begin label '"<<name<<"'");
-	}
+    void endLabel(FileLine* fl, AstNode* nodep, string* endnamep) {
+        endLabel(fl, nodep->prettyName(), endnamep);
+    }
+    void endLabel(FileLine* fl, const string& name, string* endnamep) {
+        if (fl && endnamep && *endnamep != "" && name != *endnamep
+            && name != AstNode::prettyName(*endnamep)) {
+            fl->v3warn(ENDLABEL,"End label '"<<*endnamep<<"' does not match begin label '"<<name<<"'");
+        }
     }
     void setVarDecl(AstVarType type) { m_varDecl = type; }
     void setDType(AstNodeDType* dtypep) {
diff --git a/test_regress/driver.pl b/test_regress/driver.pl
index abc61c93f..24640f9c0 100755
--- a/test_regress/driver.pl
+++ b/test_regress/driver.pl
@@ -1498,10 +1498,9 @@ sub _run {
 
     # Read the log file a couple of times to allow for NFS delays
     if ($param{check_finished} || $param{expect}) {
-        my $tries = $self->tries;
-        for (my $try=$tries-1; $try>=0; $try--) {
-            sleep 1 if ($try!=$tries-1);
-            my $moretry = $try!=0;
+        for (my $try = $self->tries - 1; $try >= 0; $try--) {
+            sleep 1 if ($try != $self->tries - 1);
+            my $moretry = $try != 0;
 
             my $fh = IO::File->new("<$param{logfile}");
             next if !$fh && $moretry;
@@ -1949,11 +1948,10 @@ sub files_identical {
     my $fn1_is_logfile = shift;
     return 1 if $self->errors || $self->skips || $self->unsupporteds;
 
-    my $tries = $self->tries;
   try:
-    for (my $try=$tries-1; $try>=0; $try--) {
-        sleep 1 if ($try!=$tries-1);
-        my $moretry = $try!=0;
+    for (my $try = $self->tries - 1; $try >= 0; $try--) {
+        sleep 1 if ($try != $self->tries - 1);
+        my $moretry = $try != 0;
 
         my $f1 = IO::File->new("<$fn1");
         my $f2 = IO::File->new("<$fn2");
diff --git a/test_regress/t/t_dpi_export_context_bad.cpp b/test_regress/t/t_dpi_export_context_bad.cpp
new file mode 100644
index 000000000..135bc7d3c
--- /dev/null
+++ b/test_regress/t/t_dpi_export_context_bad.cpp
@@ -0,0 +1,45 @@
+// -*- mode: C++; c-file-style: "cc-mode" -*-
+//
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2010 by Wilson Snyder.
+
+#include <verilated.h>
+#include VM_PREFIX_INCLUDE
+
+//======================================================================
+
+#if defined(VERILATOR)
+# include "Vt_dpi_export_context_bad__Dpi.h"
+#elif defined(VCS)
+# include "../vc_hdrs.h"
+#elif defined(CADENCE)
+# define NEED_EXTERNS
+#else
+# error "Unknown simulator for DPI test"
+#endif
+
+#ifdef NEED_EXTERNS
+extern "C" {
+    extern void dpix_task();
+}
+#endif
+
+//======================================================================
+
+unsigned int main_time = 0;
+
+double sc_time_stamp() { return main_time; }
+
+VM_PREFIX* topp = NULL;
+
+int main(int argc, char* argv[]) {
+    topp = new VM_PREFIX;
+
+    Verilated::debug(0);
+
+    topp->eval();
+    dpix_task();  // Missing svSetScope
+    return 1;
+}
diff --git a/test_regress/t/t_dpi_export_context_bad.out b/test_regress/t/t_dpi_export_context_bad.out
new file mode 100644
index 000000000..dc2091af3
--- /dev/null
+++ b/test_regress/t/t_dpi_export_context_bad.out
@@ -0,0 +1,2 @@
+%Error: unknown:0: Testbench C called 'dpix_task' but scope wasn't set, perhaps due to dpi import call without 'context', or missing svSetScope. See IEEE 1800-2017 35.5.3.
+Aborting...
diff --git a/test_regress/t/t_dpi_export_context_bad.pl b/test_regress/t/t_dpi_export_context_bad.pl
new file mode 100755
index 000000000..72e2ef077
--- /dev/null
+++ b/test_regress/t/t_dpi_export_context_bad.pl
@@ -0,0 +1,23 @@
+#!/usr/bin/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.
+
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--exe $Self->{t_dir}/t_dpi_export_context_bad.cpp"],
+    make_main => 0,
+    );
+
+execute(
+    fails => 1,
+    expect_filename => $Self->{golden_filename},
+    );
+
+ok(1);
+1;
diff --git a/test_regress/t/t_dpi_export_context_bad.v b/test_regress/t/t_dpi_export_context_bad.v
new file mode 100644
index 000000000..ec52623af
--- /dev/null
+++ b/test_regress/t/t_dpi_export_context_bad.v
@@ -0,0 +1,13 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// Copyright 2020 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.
+
+module t;
+   export "DPI-C" task dpix_task;
+   task dpix_task();
+      $write("Hello in %m\n");
+   endtask
+endmodule
diff --git a/test_regress/t/t_interface_parameter_access.v b/test_regress/t/t_interface_parameter_access.v
index 40f363153..f21948da8 100644
--- a/test_regress/t/t_interface_parameter_access.v
+++ b/test_regress/t/t_interface_parameter_access.v
@@ -34,14 +34,17 @@ module t (/*AUTOARG*/
    input clk;
 
    test_if #( .FOO (identity(5)) ) the_interface ();
+   test_if #( .FOO (identity(7)) ) array_interface [1:0] ();
 
    testmod testmod_i (.clk (clk),
 		      .intf (the_interface),
-                      .intf_no_mp (the_interface)
+                      .intf_no_mp (the_interface),
+                      .intf_array (array_interface)
                       );
 
    localparam THE_TOP_FOO = the_interface.FOO;
    localparam THE_TOP_FOO_BITS = $bits({the_interface.FOO, the_interface.FOO});
+   localparam THE_ARRAY_FOO = array_interface[0].FOO;
 
    initial begin
       if (THE_TOP_FOO != 5) begin
@@ -52,6 +55,10 @@ module t (/*AUTOARG*/
          $display("%%Error: THE_TOP_FOO_BITS = %0d", THE_TOP_FOO_BITS);
 	 $stop;
       end
+      if (THE_ARRAY_FOO != 7) begin
+         $display("%%Error: THE_ARRAY_FOO = %0d", THE_ARRAY_FOO);
+	 $stop;
+      end
    end
 
 endmodule
@@ -61,11 +68,13 @@ module testmod
   (
    input clk,
    test_if.mp intf,
-   test_if intf_no_mp
+   test_if intf_no_mp,
+   test_if.mp intf_array [1:0]
    );
 
    localparam THE_FOO = intf.FOO;
    localparam THE_OTHER_FOO = intf_no_mp.FOO;
+   localparam THE_ARRAY_FOO = intf_array[0].FOO;
 
    always @(posedge clk) begin
       if (THE_FOO != 5) begin
@@ -76,6 +85,10 @@ module testmod
          $display("%%Error: THE_OTHER_FOO = %0d", THE_OTHER_FOO);
          $stop;
       end
+      if (THE_ARRAY_FOO != 7) begin
+         $display("%%Error: THE_ARRAY_FOO = %0d", THE_ARRAY_FOO);
+         $stop;
+      end
       if (intf.FOO != 5) begin
          $display("%%Error: intf.FOO = %0d", intf.FOO);
 	 $stop;
@@ -84,6 +97,10 @@ module testmod
          $display("%%Error: intf_no_mp.FOO = %0d", intf_no_mp.FOO);
          $stop;
       end
+      if (intf_array[0].FOO != 7) begin
+         $display("%%Error: intf_array[0].FOO = %0d", intf_array[0].FOO);
+         $stop;
+      end
       //      if (i.getFoo() != 5) begin
       //         $display("%%Error: i.getFoo() = %0d", i.getFoo());
       //	 $stop;